diff options
Diffstat (limited to 'third_party/webrender/swgl/src/swgl_ext.h')
| -rw-r--r-- | third_party/webrender/swgl/src/swgl_ext.h | 1826 |
1 files changed, 0 insertions, 1826 deletions
diff --git a/third_party/webrender/swgl/src/swgl_ext.h b/third_party/webrender/swgl/src/swgl_ext.h deleted file mode 100644 index 52d240e0818..00000000000 --- a/third_party/webrender/swgl/src/swgl_ext.h +++ /dev/null @@ -1,1826 +0,0 @@ -/* This Source Code Form is subject to the terms of the Mozilla Public - * License, v. 2.0. If a copy of the MPL was not distributed with this - * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ - -// When using a solid color with clip masking, the cost of loading the clip mask -// in the blend stage exceeds the cost of processing the color. Here we handle -// the entire span of clip mask texture before the blend stage to more -// efficiently process it and modulate it with color without incurring blend -// stage overheads. -template <typename P, typename C> -static void commit_masked_solid_span(P* buf, C color, int len) { - override_clip_mask(); - uint8_t* mask = get_clip_mask(buf); - for (P* end = &buf[len]; buf < end; buf += 4, mask += 4) { - commit_span( - buf, - blend_span( - buf, - applyColor(expand_mask(buf, unpack(unaligned_load<PackedR8>(mask))), - color))); - } - restore_clip_mask(); -} - -// When using a solid color with anti-aliasing, most of the solid span will not -// benefit from anti-aliasing in the opaque region. We only want to apply the AA -// blend stage in the non-opaque start and end of the span where AA is needed. -template <typename P, typename R> -static ALWAYS_INLINE void commit_aa_solid_span(P* buf, R r, int len) { - if (int start = min((get_aa_opaque_start(buf) + 3) & ~3, len)) { - commit_solid_span<true>(buf, r, start); - buf += start; - len -= start; - } - if (int opaque = min((get_aa_opaque_size(buf) + 3) & ~3, len)) { - override_aa(); - commit_solid_span<true>(buf, r, opaque); - restore_aa(); - buf += opaque; - len -= opaque; - } - if (len > 0) { - commit_solid_span<true>(buf, r, len); - } -} - -// Forces a value with vector run-class to have scalar run-class. -template <typename T> -static ALWAYS_INLINE auto swgl_forceScalar(T v) -> decltype(force_scalar(v)) { - return force_scalar(v); -} - -// Advance all varying inperpolants by a single chunk -#define swgl_stepInterp() step_interp_inputs() - -// Pseudo-intrinsic that accesses the interpolation step for a given varying -#define swgl_interpStep(v) (interp_step.v) - -// Commit an entire span of a solid color. This dispatches to clip-masked and -// anti-aliased fast-paths as appropriate. -#define swgl_commitSolid(format, v, n) \ - do { \ - int len = (n); \ - if (blend_key) { \ - if (swgl_ClipFlags & SWGL_CLIP_FLAG_MASK) { \ - commit_masked_solid_span(swgl_Out##format, \ - packColor(swgl_Out##format, (v)), len); \ - } else if (swgl_ClipFlags & SWGL_CLIP_FLAG_AA) { \ - commit_aa_solid_span(swgl_Out##format, \ - pack_span(swgl_Out##format, (v)), len); \ - } else { \ - commit_solid_span<true>(swgl_Out##format, \ - pack_span(swgl_Out##format, (v)), len); \ - } \ - } else { \ - commit_solid_span<false>(swgl_Out##format, \ - pack_span(swgl_Out##format, (v)), len); \ - } \ - swgl_Out##format += len; \ - swgl_SpanLength -= len; \ - } while (0) -#define swgl_commitSolidRGBA8(v) swgl_commitSolid(RGBA8, v, swgl_SpanLength) -#define swgl_commitSolidR8(v) swgl_commitSolid(R8, v, swgl_SpanLength) -#define swgl_commitPartialSolidRGBA8(len, v) \ - swgl_commitSolid(RGBA8, v, min(int(len), swgl_SpanLength)) -#define swgl_commitPartialSolidR8(len, v) \ - swgl_commitSolid(R8, v, min(int(len), swgl_SpanLength)) - -#define swgl_commitChunk(format, chunk) \ - do { \ - auto r = chunk; \ - if (blend_key) r = blend_span(swgl_Out##format, r); \ - commit_span(swgl_Out##format, r); \ - swgl_Out##format += swgl_StepSize; \ - swgl_SpanLength -= swgl_StepSize; \ - } while (0) - -// Commit a single chunk of a color -#define swgl_commitColor(format, color) \ - swgl_commitChunk(format, pack_pixels_##format(color)) -#define swgl_commitColorRGBA8(color) swgl_commitColor(RGBA8, color) -#define swgl_commitColorR8(color) swgl_commitColor(R8, color) - -template <typename S> -static ALWAYS_INLINE bool swgl_isTextureLinear(S s) { - return s->filter == TextureFilter::LINEAR; -} - -template <typename S> -static ALWAYS_INLINE bool swgl_isTextureRGBA8(S s) { - return s->format == TextureFormat::RGBA8; -} - -template <typename S> -static ALWAYS_INLINE bool swgl_isTextureR8(S s) { - return s->format == TextureFormat::R8; -} - -// Use the default linear quantization scale of 128. This gives 7 bits of -// fractional precision, which when multiplied with a signed 9 bit value -// still fits in a 16 bit integer. -const int swgl_LinearQuantizeScale = 128; - -// Quantizes UVs for access into a linear texture. -template <typename S, typename T> -static ALWAYS_INLINE T swgl_linearQuantize(S s, T p) { - return linearQuantize(p, swgl_LinearQuantizeScale, s); -} - -// Quantizes an interpolation step for UVs for access into a linear texture. -template <typename S, typename T> -static ALWAYS_INLINE T swgl_linearQuantizeStep(S s, T p) { - return samplerScale(s, p) * swgl_LinearQuantizeScale; -} - -template <typename S> -static ALWAYS_INLINE WideRGBA8 textureLinearUnpacked(UNUSED uint32_t* buf, - S sampler, ivec2 i) { - return textureLinearUnpackedRGBA8(sampler, i); -} - -template <typename S> -static ALWAYS_INLINE WideR8 textureLinearUnpacked(UNUSED uint8_t* buf, - S sampler, ivec2 i) { - return textureLinearUnpackedR8(sampler, i); -} - -template <typename S> -static ALWAYS_INLINE bool matchTextureFormat(S s, UNUSED uint32_t* buf) { - return swgl_isTextureRGBA8(s); -} - -template <typename S> -static ALWAYS_INLINE bool matchTextureFormat(S s, UNUSED uint8_t* buf) { - return swgl_isTextureR8(s); -} - -// Quantizes the UVs to the 2^7 scale needed for calculating fractional offsets -// for linear sampling. -#define LINEAR_QUANTIZE_UV(sampler, uv, uv_step, uv_rect, min_uv, max_uv) \ - uv = swgl_linearQuantize(sampler, uv); \ - vec2_scalar uv_step = \ - float(swgl_StepSize) * vec2_scalar{uv.x.y - uv.x.x, uv.y.y - uv.y.x}; \ - vec2_scalar min_uv = max( \ - swgl_linearQuantize(sampler, vec2_scalar{uv_rect.x, uv_rect.y}), 0.0f); \ - vec2_scalar max_uv = \ - max(swgl_linearQuantize(sampler, vec2_scalar{uv_rect.z, uv_rect.w}), \ - min_uv); - -// Implements the fallback linear filter that can deal with clamping and -// arbitrary scales. -template <bool BLEND, typename S, typename C, typename P> -static P* blendTextureLinearFallback(S sampler, vec2 uv, int span, - vec2_scalar uv_step, vec2_scalar min_uv, - vec2_scalar max_uv, C color, P* buf) { - for (P* end = buf + span; buf < end; buf += swgl_StepSize, uv += uv_step) { - commit_blend_span<BLEND>( - buf, applyColor(textureLinearUnpacked(buf, sampler, - ivec2(clamp(uv, min_uv, max_uv))), - color)); - } - return buf; -} - -static ALWAYS_INLINE U64 castForShuffle(V16<int16_t> r) { - return bit_cast<U64>(r); -} -static ALWAYS_INLINE U16 castForShuffle(V4<int16_t> r) { - return bit_cast<U16>(r); -} - -static ALWAYS_INLINE V16<int16_t> applyFracX(V16<int16_t> r, I16 fracx) { - return r * fracx.xxxxyyyyzzzzwwww; -} -static ALWAYS_INLINE V4<int16_t> applyFracX(V4<int16_t> r, I16 fracx) { - return r * fracx; -} - -// Implements a faster linear filter that works with axis-aligned constant Y but -// scales less than 1, i.e. upscaling. In this case we can optimize for the -// constant Y fraction as well as load all chunks from memory in a single tap -// for each row. -template <bool BLEND, typename S, typename C, typename P> -static void blendTextureLinearUpscale(S sampler, vec2 uv, int span, - vec2_scalar uv_step, vec2_scalar min_uv, - vec2_scalar max_uv, C color, P* buf) { - typedef VectorType<uint8_t, 4 * sizeof(P)> packed_type; - typedef VectorType<uint16_t, 4 * sizeof(P)> unpacked_type; - typedef VectorType<int16_t, 4 * sizeof(P)> signed_unpacked_type; - - ivec2 i(clamp(uv, min_uv, max_uv)); - ivec2 frac = i; - i >>= 7; - P* row0 = (P*)sampler->buf + computeRow(sampler, ivec2_scalar(0, i.y.x)); - P* row1 = row0 + computeNextRowOffset(sampler, ivec2_scalar(0, i.y.x)); - I16 fracx = computeFracX(sampler, i, frac); - int16_t fracy = computeFracY(frac).x; - auto src0 = - CONVERT(unaligned_load<packed_type>(&row0[i.x.x]), signed_unpacked_type); - auto src1 = - CONVERT(unaligned_load<packed_type>(&row1[i.x.x]), signed_unpacked_type); - auto src = castForShuffle(src0 + (((src1 - src0) * fracy) >> 7)); - - // We attempt to sample ahead by one chunk and interpolate it with the current - // one. However, due to the complication of upscaling, we may not necessarily - // shift in all the next set of samples. - for (P* end = buf + span; buf < end; buf += 4) { - uv.x += uv_step.x; - I32 ixn = cast(uv.x); - I16 fracn = computeFracNoClamp(ixn); - ixn >>= 7; - auto src0n = CONVERT(unaligned_load<packed_type>(&row0[ixn.x]), - signed_unpacked_type); - auto src1n = CONVERT(unaligned_load<packed_type>(&row1[ixn.x]), - signed_unpacked_type); - auto srcn = castForShuffle(src0n + (((src1n - src0n) * fracy) >> 7)); - - // Since we're upscaling, we know that a source pixel has a larger footprint - // than the destination pixel, and thus all the source pixels needed for - // this chunk will fall within a single chunk of texture data. However, - // since the source pixels don't map 1:1 with destination pixels, we need to - // shift the source pixels over based on their offset from the start of the - // chunk. This could conceivably be optimized better with usage of PSHUFB or - // VTBL instructions However, since PSHUFB requires SSSE3, instead we resort - // to masking in the correct pixels to avoid having to index into memory. - // For the last sample to interpolate with, we need to potentially shift in - // a sample from the next chunk over in the case the samples fill out an - // entire chunk. - auto shuf = src; - auto shufn = SHUFFLE(src, ixn.x == i.x.w ? srcn.yyyy : srcn, 1, 2, 3, 4); - if (i.x.y == i.x.x) { - shuf = shuf.xxyz; - shufn = shufn.xxyz; - } - if (i.x.z == i.x.y) { - shuf = shuf.xyyz; - shufn = shufn.xyyz; - } - if (i.x.w == i.x.z) { - shuf = shuf.xyzz; - shufn = shufn.xyzz; - } - - // Convert back to a signed unpacked type so that we can interpolate the - // final result. - auto interp = bit_cast<signed_unpacked_type>(shuf); - auto interpn = bit_cast<signed_unpacked_type>(shufn); - interp += applyFracX(interpn - interp, fracx) >> 7; - - commit_blend_span<BLEND>( - buf, applyColor(bit_cast<unpacked_type>(interp), color)); - - i.x = ixn; - fracx = fracn; - src = srcn; - } -} - -// This is the fastest variant of the linear filter that still provides -// filtering. In cases where there is no scaling required, but we have a -// subpixel offset that forces us to blend in neighboring pixels, we can -// optimize away most of the memory loads and shuffling that is required by the -// fallback filter. -template <bool BLEND, typename S, typename C, typename P> -static void blendTextureLinearFast(S sampler, vec2 uv, int span, - vec2_scalar min_uv, vec2_scalar max_uv, - C color, P* buf) { - typedef VectorType<uint8_t, 4 * sizeof(P)> packed_type; - typedef VectorType<uint16_t, 4 * sizeof(P)> unpacked_type; - typedef VectorType<int16_t, 4 * sizeof(P)> signed_unpacked_type; - - ivec2 i(clamp(uv, min_uv, max_uv)); - ivec2 frac = i; - i >>= 7; - P* row0 = (P*)sampler->buf + computeRow(sampler, force_scalar(i)); - P* row1 = row0 + computeNextRowOffset(sampler, force_scalar(i)); - int16_t fracx = computeFracX(sampler, i, frac).x; - int16_t fracy = computeFracY(frac).x; - auto src0 = CONVERT(unaligned_load<packed_type>(row0), signed_unpacked_type); - auto src1 = CONVERT(unaligned_load<packed_type>(row1), signed_unpacked_type); - auto src = castForShuffle(src0 + (((src1 - src0) * fracy) >> 7)); - - // Since there is no scaling, we sample ahead by one chunk and interpolate it - // with the current one. We can then reuse this value on the next iteration. - for (P* end = buf + span; buf < end; buf += 4) { - row0 += 4; - row1 += 4; - auto src0n = - CONVERT(unaligned_load<packed_type>(row0), signed_unpacked_type); - auto src1n = - CONVERT(unaligned_load<packed_type>(row1), signed_unpacked_type); - auto srcn = castForShuffle(src0n + (((src1n - src0n) * fracy) >> 7)); - - // For the last sample to interpolate with, we need to potentially shift in - // a sample from the next chunk over since the samples fill out an entire - // chunk. - auto interp = bit_cast<signed_unpacked_type>(src); - auto interpn = - bit_cast<signed_unpacked_type>(SHUFFLE(src, srcn, 1, 2, 3, 4)); - interp += ((interpn - interp) * fracx) >> 7; - - commit_blend_span<BLEND>( - buf, applyColor(bit_cast<unpacked_type>(interp), color)); - - src = srcn; - } -} - -// Implements a faster linear filter that works with axis-aligned constant Y but -// downscaling the texture by half. In this case we can optimize for the -// constant X/Y fractions and reduction factor while minimizing shuffling. -template <bool BLEND, typename S, typename C, typename P> -static NO_INLINE void blendTextureLinearDownscale(S sampler, vec2 uv, int span, - vec2_scalar min_uv, - vec2_scalar max_uv, C color, - P* buf) { - typedef VectorType<uint8_t, 4 * sizeof(P)> packed_type; - typedef VectorType<uint16_t, 4 * sizeof(P)> unpacked_type; - typedef VectorType<int16_t, 4 * sizeof(P)> signed_unpacked_type; - - ivec2 i(clamp(uv, min_uv, max_uv)); - ivec2 frac = i; - i >>= 7; - P* row0 = (P*)sampler->buf + computeRow(sampler, force_scalar(i)); - P* row1 = row0 + computeNextRowOffset(sampler, force_scalar(i)); - int16_t fracx = computeFracX(sampler, i, frac).x; - int16_t fracy = computeFracY(frac).x; - - for (P* end = buf + span; buf < end; buf += 4) { - auto src0 = - CONVERT(unaligned_load<packed_type>(row0), signed_unpacked_type); - auto src1 = - CONVERT(unaligned_load<packed_type>(row1), signed_unpacked_type); - auto src = castForShuffle(src0 + (((src1 - src0) * fracy) >> 7)); - row0 += 4; - row1 += 4; - auto src0n = - CONVERT(unaligned_load<packed_type>(row0), signed_unpacked_type); - auto src1n = - CONVERT(unaligned_load<packed_type>(row1), signed_unpacked_type); - auto srcn = castForShuffle(src0n + (((src1n - src0n) * fracy) >> 7)); - row0 += 4; - row1 += 4; - - auto interp = - bit_cast<signed_unpacked_type>(SHUFFLE(src, srcn, 0, 2, 4, 6)); - auto interpn = - bit_cast<signed_unpacked_type>(SHUFFLE(src, srcn, 1, 3, 5, 7)); - interp += ((interpn - interp) * fracx) >> 7; - - commit_blend_span<BLEND>( - buf, applyColor(bit_cast<unpacked_type>(interp), color)); - } -} - -enum LinearFilter { - // No linear filter is needed. - LINEAR_FILTER_NEAREST = 0, - // The most general linear filter that handles clamping and varying scales. - LINEAR_FILTER_FALLBACK, - // A linear filter optimized for axis-aligned upscaling. - LINEAR_FILTER_UPSCALE, - // A linear filter with no scaling but with subpixel offset. - LINEAR_FILTER_FAST, - // A linear filter optimized for 2x axis-aligned downscaling. - LINEAR_FILTER_DOWNSCALE -}; - -// Dispatches to an appropriate linear filter depending on the selected filter. -template <bool BLEND, typename S, typename C, typename P> -static P* blendTextureLinearDispatch(S sampler, vec2 uv, int span, - vec2_scalar uv_step, vec2_scalar min_uv, - vec2_scalar max_uv, C color, P* buf, - LinearFilter filter) { - P* end = buf + span; - if (filter != LINEAR_FILTER_FALLBACK) { - // If we're not using the fallback, then Y is constant across the entire - // row. We just need to ensure that we handle any samples that might pull - // data from before the start of the row and require clamping. - float beforeDist = max(0.0f, min_uv.x) - uv.x.x; - if (beforeDist > 0) { - int before = clamp(int(ceil(beforeDist / uv_step.x)) * swgl_StepSize, 0, - int(end - buf)); - buf = blendTextureLinearFallback<BLEND>(sampler, uv, before, uv_step, - min_uv, max_uv, color, buf); - uv.x += (before / swgl_StepSize) * uv_step.x; - } - // We need to check how many samples we can take from inside the row without - // requiring clamping. In case the filter oversamples the row by a step, we - // subtract off a step from the width to leave some room. - float insideDist = - min(max_uv.x, float((int(sampler->width) - swgl_StepSize) * - swgl_LinearQuantizeScale)) - - uv.x.x; - if (uv_step.x > 0.0f && insideDist >= uv_step.x) { - int inside = int(end - buf); - if (filter == LINEAR_FILTER_DOWNSCALE) { - inside = clamp(int(insideDist * (0.5f / swgl_LinearQuantizeScale)) & - ~(swgl_StepSize - 1), - 0, inside); - blendTextureLinearDownscale<BLEND>(sampler, uv, inside, min_uv, max_uv, - color, buf); - } else if (filter == LINEAR_FILTER_UPSCALE) { - inside = clamp(int(insideDist / uv_step.x) * swgl_StepSize, 0, inside); - blendTextureLinearUpscale<BLEND>(sampler, uv, inside, uv_step, min_uv, - max_uv, color, buf); - } else { - inside = clamp(int(insideDist * (1.0f / swgl_LinearQuantizeScale)) & - ~(swgl_StepSize - 1), - 0, inside); - blendTextureLinearFast<BLEND>(sampler, uv, inside, min_uv, max_uv, - color, buf); - } - buf += inside; - uv.x += (inside / swgl_StepSize) * uv_step.x; - } - } - // If the fallback filter was requested, or if there are any samples left that - // may be outside the row and require clamping, then handle that with here. - if (buf < end) { - buf = blendTextureLinearFallback<BLEND>( - sampler, uv, int(end - buf), uv_step, min_uv, max_uv, color, buf); - } - return buf; -} - -// Helper function to quantize UVs for linear filtering before dispatch -template <bool BLEND, typename S, typename C, typename P> -static inline int blendTextureLinear(S sampler, vec2 uv, int span, - const vec4_scalar& uv_rect, C color, - P* buf, LinearFilter filter) { - if (!matchTextureFormat(sampler, buf)) { - return 0; - } - LINEAR_QUANTIZE_UV(sampler, uv, uv_step, uv_rect, min_uv, max_uv); - blendTextureLinearDispatch<BLEND>(sampler, uv, span, uv_step, min_uv, max_uv, - color, buf, filter); - return span; -} - -// Samples an axis-aligned span of on a single row of a texture using 1:1 -// nearest filtering. Sampling is constrained to only fall within the given UV -// bounds. This requires a pointer to the destination buffer. An optional color -// modulus can be supplied. -template <bool BLEND, typename S, typename C, typename P> -static int blendTextureNearestFast(S sampler, vec2 uv, int span, - const vec4_scalar& uv_rect, C color, - P* buf) { - if (!matchTextureFormat(sampler, buf)) { - return 0; - } - - typedef VectorType<uint8_t, 4 * sizeof(P)> packed_type; - - ivec2_scalar i = make_ivec2(samplerScale(sampler, force_scalar(uv))); - ivec2_scalar minUV = - make_ivec2(samplerScale(sampler, vec2_scalar{uv_rect.x, uv_rect.y})); - ivec2_scalar maxUV = - make_ivec2(samplerScale(sampler, vec2_scalar{uv_rect.z, uv_rect.w})); - - // Calculate the row pointer within the buffer, clamping to within valid row - // bounds. - P* row = - &((P*)sampler - ->buf)[clamp(clampCoord(i.y, sampler->height), minUV.y, maxUV.y) * - sampler->stride]; - // Find clamped X bounds within the row. - int minX = clamp(minUV.x, 0, sampler->width - 1); - int maxX = clamp(maxUV.x, minX, sampler->width - 1); - int curX = i.x; - int endX = i.x + span; - // If we need to start sampling below the valid sample bounds, then we need to - // fill this section with a constant clamped sample. - if (curX < minX) { - int n = min(minX, endX) - curX; - auto src = - applyColor(unpack(bit_cast<packed_type>(V4<P>(row[minX]))), color); - commit_solid_span<BLEND>(buf, src, n); - buf += n; - curX += n; - } - // Here we only deal with valid samples within the sample bounds. No clamping - // should occur here within these inner loops. - int n = max(min(maxX + 1, endX) - curX, 0); - // Try to process as many chunks as possible with full loads and stores. - for (int end = curX + (n & ~3); curX < end; curX += 4, buf += 4) { - auto src = applyColor(unaligned_load<packed_type>(&row[curX]), color); - commit_blend_span<BLEND>(buf, src); - } - n &= 3; - // If we have any leftover samples after processing chunks, use partial loads - // and stores. - if (n > 0) { - auto src = applyColor(partial_load_span<packed_type>(&row[curX], n), color); - commit_blend_span<BLEND>(buf, src, n); - buf += n; - curX += n; - } - // If we still have samples left above the valid sample bounds, then we again - // need to fill this section with a constant clamped sample. - if (curX < endX) { - auto src = - applyColor(unpack(bit_cast<packed_type>(V4<P>(row[maxX]))), color); - commit_solid_span<BLEND>(buf, src, endX - curX); - } - return span; -} - -// We need to verify that the pixel step reasonably approximates stepping by a -// single texel for every pixel we need to reproduce. Try to ensure that the -// margin of error is no more than approximately 2^-7. Also, we check here if -// the scaling can be quantized for acceleration. -template <typename T> -static ALWAYS_INLINE int spanNeedsScale(int span, T P) { - span &= ~(128 - 1); - span += 128; - int scaled = round((P.x.y - P.x.x) * span); - return scaled != span ? (scaled == span * 2 ? 2 : 1) : 0; -} - -// Helper function to decide whether we can safely apply 1:1 nearest filtering -// without diverging too much from the linear filter. -template <typename S, typename T> -static inline LinearFilter needsTextureLinear(S sampler, T P, int span) { - // First verify if the row Y doesn't change across samples - if (P.y.x != P.y.y) { - return LINEAR_FILTER_FALLBACK; - } - P = samplerScale(sampler, P); - if (int scale = spanNeedsScale(span, P)) { - // If the source region is not flipped and smaller than the destination, - // then we can use the upscaling filter since row Y is constant. - return P.x.x < P.x.y && P.x.y - P.x.x <= 1 - ? LINEAR_FILTER_UPSCALE - : (scale == 2 ? LINEAR_FILTER_DOWNSCALE - : LINEAR_FILTER_FALLBACK); - } - // Also verify that we're reasonably close to the center of a texel - // so that it doesn't look that much different than if a linear filter - // was used. - if ((int(P.x.x * 4.0f + 0.5f) & 3) != 2 || - (int(P.y.x * 4.0f + 0.5f) & 3) != 2) { - // The source and destination regions are the same, but there is a - // significant subpixel offset. We can use a faster linear filter to deal - // with the offset in this case. - return LINEAR_FILTER_FAST; - } - // Otherwise, we have a constant 1:1 step and we're stepping reasonably close - // to the center of each pixel, so it's safe to disable the linear filter and - // use nearest. - return LINEAR_FILTER_NEAREST; -} - -// Commit an entire span with linear filtering -#define swgl_commitTextureLinear(format, s, p, uv_rect, color, n) \ - do { \ - auto packed_color = packColor(swgl_Out##format, color); \ - int len = (n); \ - int drawn = 0; \ - if (LinearFilter filter = needsTextureLinear(s, p, len)) { \ - if (blend_key) { \ - drawn = blendTextureLinear<true>(s, p, len, uv_rect, packed_color, \ - swgl_Out##format, filter); \ - } else { \ - drawn = blendTextureLinear<false>(s, p, len, uv_rect, packed_color, \ - swgl_Out##format, filter); \ - } \ - } else if (blend_key) { \ - drawn = blendTextureNearestFast<true>(s, p, len, uv_rect, packed_color, \ - swgl_Out##format); \ - } else { \ - drawn = blendTextureNearestFast<false>(s, p, len, uv_rect, packed_color, \ - swgl_Out##format); \ - } \ - swgl_Out##format += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) -#define swgl_commitTextureLinearRGBA8(s, p, uv_rect) \ - swgl_commitTextureLinear(RGBA8, s, p, uv_rect, NoColor(), swgl_SpanLength) -#define swgl_commitTextureLinearR8(s, p, uv_rect) \ - swgl_commitTextureLinear(R8, s, p, uv_rect, NoColor(), swgl_SpanLength) - -// Commit a partial span with linear filtering, optionally inverting the color -#define swgl_commitPartialTextureLinearR8(len, s, p, uv_rect) \ - swgl_commitTextureLinear(R8, s, p, uv_rect, NoColor(), \ - min(int(len), swgl_SpanLength)) -#define swgl_commitPartialTextureLinearInvertR8(len, s, p, uv_rect) \ - swgl_commitTextureLinear(R8, s, p, uv_rect, InvertColor(), \ - min(int(len), swgl_SpanLength)) - -// Commit an entire span with linear filtering that is scaled by a color -#define swgl_commitTextureLinearColorRGBA8(s, p, uv_rect, color) \ - swgl_commitTextureLinear(RGBA8, s, p, uv_rect, color, swgl_SpanLength) -#define swgl_commitTextureLinearColorR8(s, p, uv_rect, color) \ - swgl_commitTextureLinear(R8, s, p, uv_rect, color, swgl_SpanLength) - -// Helper function that samples from an R8 texture while expanding it to support -// a differing framebuffer format. -template <bool BLEND, typename S, typename C, typename P> -static inline int blendTextureLinearR8(S sampler, vec2 uv, int span, - const vec4_scalar& uv_rect, C color, - P* buf) { - if (!swgl_isTextureR8(sampler)) { - return 0; - } - LINEAR_QUANTIZE_UV(sampler, uv, uv_step, uv_rect, min_uv, max_uv); - for (P* end = buf + span; buf < end; buf += swgl_StepSize, uv += uv_step) { - commit_blend_span<BLEND>( - buf, applyColor(expand_mask(buf, textureLinearUnpackedR8( - sampler, - ivec2(clamp(uv, min_uv, max_uv)))), - color)); - } - return span; -} - -// Commit an entire span with linear filtering while expanding from R8 to RGBA8 -#define swgl_commitTextureLinearColorR8ToRGBA8(s, p, uv_rect, color) \ - do { \ - auto packed_color = packColor(swgl_OutRGBA8, color); \ - int drawn = 0; \ - if (blend_key) { \ - drawn = blendTextureLinearR8<true>(s, p, swgl_SpanLength, uv_rect, \ - packed_color, swgl_OutRGBA8); \ - } else { \ - drawn = blendTextureLinearR8<false>(s, p, swgl_SpanLength, uv_rect, \ - packed_color, swgl_OutRGBA8); \ - } \ - swgl_OutRGBA8 += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) -#define swgl_commitTextureLinearR8ToRGBA8(s, p, uv_rect) \ - swgl_commitTextureLinearColorR8ToRGBA8(s, p, uv_rect, NoColor()) - -// Compute repeating UVs, possibly constrained by tile repeat limits -static inline vec2 tileRepeatUV(vec2 uv, const vec2_scalar& tile_repeat) { - if (tile_repeat.x > 0.0f) { - // Clamp to a number slightly less than the tile repeat limit so that - // it results in a number close to but not equal to 1 after fract(). - // This avoids fract() yielding 0 if the limit was left as whole integer. - uv = clamp(uv, vec2_scalar(0.0f), tile_repeat - 1.0e-6f); - } - return fract(uv); -} - -// Compute the number of non-repeating steps before we need to potentially -// repeat the UVs. -static inline int computeNoRepeatSteps(Float uv, float uv_step, - float tile_repeat, int steps) { - if (uv.w < uv.x) { - // Ensure the UV taps are ordered low to high. - uv = uv.wzyx; - } - // Check if the samples cross the boundary of the next whole integer or the - // tile repeat limit, whichever is lower. - float limit = floor(uv.x) + 1.0f; - if (tile_repeat > 0.0f) { - limit = min(limit, tile_repeat); - } - return uv.x >= 0.0f && uv.w < limit - ? (uv_step != 0.0f - ? int(min(float(steps), (limit - uv.x) / uv_step)) - : steps) - : 0; -} - -// Blends an entire span of texture with linear filtering and repeating UVs. -template <bool BLEND, typename S, typename C, typename P> -static int blendTextureLinearRepeat(S sampler, vec2 uv, int span, - const vec2_scalar& tile_repeat, - const vec4_scalar& uv_repeat, - const vec4_scalar& uv_rect, C color, - P* buf) { - if (!matchTextureFormat(sampler, buf)) { - return 0; - } - vec2_scalar uv_scale = {uv_repeat.z - uv_repeat.x, uv_repeat.w - uv_repeat.y}; - vec2_scalar uv_offset = {uv_repeat.x, uv_repeat.y}; - // Choose a linear filter to use for no-repeat sub-spans - LinearFilter filter = - needsTextureLinear(sampler, uv * uv_scale + uv_offset, span); - // We need to step UVs unscaled and unquantized so that we can modulo them - // with fract. We use uv_scale and uv_offset to map them into the correct - // range. - vec2_scalar uv_step = - float(swgl_StepSize) * vec2_scalar{uv.x.y - uv.x.x, uv.y.y - uv.y.x}; - uv_scale = swgl_linearQuantizeStep(sampler, uv_scale); - uv_offset = swgl_linearQuantize(sampler, uv_offset); - vec2_scalar min_uv = max( - swgl_linearQuantize(sampler, vec2_scalar{uv_rect.x, uv_rect.y}), 0.0f); - vec2_scalar max_uv = max( - swgl_linearQuantize(sampler, vec2_scalar{uv_rect.z, uv_rect.w}), min_uv); - for (P* end = buf + span; buf < end; buf += swgl_StepSize, uv += uv_step) { - int steps = int(end - buf) / swgl_StepSize; - // Find the sub-span before UVs repeat to avoid expensive repeat math - steps = computeNoRepeatSteps(uv.x, uv_step.x, tile_repeat.x, steps); - if (steps > 0) { - steps = computeNoRepeatSteps(uv.y, uv_step.y, tile_repeat.y, steps); - if (steps > 0) { - buf = blendTextureLinearDispatch<BLEND>( - sampler, fract(uv) * uv_scale + uv_offset, steps * swgl_StepSize, - uv_step * uv_scale, min_uv, max_uv, color, buf, filter); - if (buf >= end) { - break; - } - uv += steps * uv_step; - } - } - // UVs might repeat within this step, so explicitly compute repeated UVs - vec2 repeated_uv = clamp( - tileRepeatUV(uv, tile_repeat) * uv_scale + uv_offset, min_uv, max_uv); - commit_blend_span<BLEND>( - buf, applyColor(textureLinearUnpacked(buf, sampler, ivec2(repeated_uv)), - color)); - } - return span; -} - -// Commit an entire span with linear filtering and repeating UVs -#define swgl_commitTextureLinearRepeat(format, s, p, tile_repeat, uv_repeat, \ - uv_rect, color) \ - do { \ - auto packed_color = packColor(swgl_Out##format, color); \ - int drawn = 0; \ - if (blend_key) { \ - drawn = blendTextureLinearRepeat<true>(s, p, swgl_SpanLength, \ - tile_repeat, uv_repeat, uv_rect, \ - packed_color, swgl_Out##format); \ - } else { \ - drawn = blendTextureLinearRepeat<false>(s, p, swgl_SpanLength, \ - tile_repeat, uv_repeat, uv_rect, \ - packed_color, swgl_Out##format); \ - } \ - swgl_Out##format += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) -#define swgl_commitTextureLinearRepeatRGBA8(s, p, tile_repeat, uv_repeat, \ - uv_rect) \ - swgl_commitTextureLinearRepeat(RGBA8, s, p, tile_repeat, uv_repeat, uv_rect, \ - NoColor()) -#define swgl_commitTextureLinearRepeatColorRGBA8(s, p, tile_repeat, uv_repeat, \ - uv_rect, color) \ - swgl_commitTextureLinearRepeat(RGBA8, s, p, tile_repeat, uv_repeat, uv_rect, \ - color) - -template <typename S> -static ALWAYS_INLINE PackedRGBA8 textureNearestPacked(UNUSED uint32_t* buf, - S sampler, ivec2 i) { - return textureNearestPackedRGBA8(sampler, i); -} - -// Blends an entire span of texture with nearest filtering and either -// repeated or clamped UVs. -template <bool BLEND, bool REPEAT, typename S, typename C, typename P> -static int blendTextureNearestRepeat(S sampler, vec2 uv, int span, - const vec2_scalar& tile_repeat, - const vec4_scalar& uv_rect, C color, - P* buf) { - if (!matchTextureFormat(sampler, buf)) { - return 0; - } - if (!REPEAT) { - // If clamping, then we step pre-scaled to the sampler. For repeat modes, - // this will be accomplished via uv_scale instead. - uv = samplerScale(sampler, uv); - } - vec2_scalar uv_step = - float(swgl_StepSize) * vec2_scalar{uv.x.y - uv.x.x, uv.y.y - uv.y.x}; - vec2_scalar min_uv = samplerScale(sampler, vec2_scalar{uv_rect.x, uv_rect.y}); - vec2_scalar max_uv = samplerScale(sampler, vec2_scalar{uv_rect.z, uv_rect.w}); - vec2_scalar uv_scale = max_uv - min_uv; - // If the effective sampling area of this texture is only a single pixel, then - // treat it as a solid span. For repeat modes, the bounds are specified on - // pixel boundaries, whereas for clamp modes, bounds are on pixel centers, so - // the test varies depending on which. If the sample range on an axis is - // greater than one pixel, we can still check if we don't move far enough from - // the pixel center on that axis to hit the next pixel. - if ((int(min_uv.x) + (REPEAT ? 1 : 0) >= int(max_uv.x) || - (uv_step.x * span * (REPEAT ? uv_scale.x : 1.0f) < 0.5f)) && - (int(min_uv.y) + (REPEAT ? 1 : 0) >= int(max_uv.y) || - (uv_step.y * span * (REPEAT ? uv_scale.y : 1.0f) < 0.5f))) { - vec2 repeated_uv = REPEAT - ? tileRepeatUV(uv, tile_repeat) * uv_scale + min_uv - : clamp(uv, min_uv, max_uv); - commit_solid_span<BLEND>(buf, - applyColor(unpack(textureNearestPacked( - buf, sampler, ivec2(repeated_uv))), - color), - span); - } else { - for (P* end = buf + span; buf < end; buf += swgl_StepSize, uv += uv_step) { - if (REPEAT) { - int steps = int(end - buf) / swgl_StepSize; - // Find the sub-span before UVs repeat to avoid expensive repeat math - steps = computeNoRepeatSteps(uv.x, uv_step.x, tile_repeat.x, steps); - if (steps > 0) { - steps = computeNoRepeatSteps(uv.y, uv_step.y, tile_repeat.y, steps); - if (steps > 0) { - vec2 inside_uv = fract(uv) * uv_scale + min_uv; - vec2 inside_step = uv_step * uv_scale; - for (P* outside = &buf[steps * swgl_StepSize]; buf < outside; - buf += swgl_StepSize, inside_uv += inside_step) { - commit_blend_span<BLEND>( - buf, applyColor( - textureNearestPacked(buf, sampler, ivec2(inside_uv)), - color)); - } - if (buf >= end) { - break; - } - uv += steps * uv_step; - } - } - } - - // UVs might repeat within this step, so explicitly compute repeated UVs - vec2 repeated_uv = REPEAT - ? tileRepeatUV(uv, tile_repeat) * uv_scale + min_uv - : clamp(uv, min_uv, max_uv); - commit_blend_span<BLEND>( - buf, - applyColor(textureNearestPacked(buf, sampler, ivec2(repeated_uv)), - color)); - } - } - return span; -} - -// Determine if we can use the fast nearest filter for the given nearest mode. -// If the Y coordinate varies more than half a pixel over -// the span (which might cause the texel to alias to the next one), or the span -// needs X scaling, then we have to use the fallback. -template <typename S, typename T> -static ALWAYS_INLINE bool needsNearestFallback(S sampler, T P, int span) { - P = samplerScale(sampler, P); - return (P.y.y - P.y.x) * span >= 0.5f || spanNeedsScale(span, P); -} - -// Commit an entire span with nearest filtering and either clamped or repeating -// UVs -#define swgl_commitTextureNearest(format, s, p, uv_rect, color) \ - do { \ - auto packed_color = packColor(swgl_Out##format, color); \ - int drawn = 0; \ - if (needsNearestFallback(s, p, swgl_SpanLength)) { \ - if (blend_key) { \ - drawn = blendTextureNearestRepeat<true, false>( \ - s, p, swgl_SpanLength, 0.0f, uv_rect, packed_color, \ - swgl_Out##format); \ - } else { \ - drawn = blendTextureNearestRepeat<false, false>( \ - s, p, swgl_SpanLength, 0.0f, uv_rect, packed_color, \ - swgl_Out##format); \ - } \ - } else if (blend_key) { \ - drawn = blendTextureNearestFast<true>(s, p, swgl_SpanLength, uv_rect, \ - packed_color, swgl_Out##format); \ - } else { \ - drawn = blendTextureNearestFast<false>(s, p, swgl_SpanLength, uv_rect, \ - packed_color, swgl_Out##format); \ - } \ - swgl_Out##format += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) -#define swgl_commitTextureNearestRGBA8(s, p, uv_rect) \ - swgl_commitTextureNearest(RGBA8, s, p, uv_rect, NoColor()) -#define swgl_commitTextureNearestColorRGBA8(s, p, uv_rect, color) \ - swgl_commitTextureNearest(RGBA8, s, p, uv_rect, color) - -#define swgl_commitTextureNearestRepeat(format, s, p, tile_repeat, uv_rect, \ - color) \ - do { \ - auto packed_color = packColor(swgl_Out##format, color); \ - int drawn = 0; \ - if (blend_key) { \ - drawn = blendTextureNearestRepeat<true, true>( \ - s, p, swgl_SpanLength, tile_repeat, uv_rect, packed_color, \ - swgl_Out##format); \ - } else { \ - drawn = blendTextureNearestRepeat<false, true>( \ - s, p, swgl_SpanLength, tile_repeat, uv_rect, packed_color, \ - swgl_Out##format); \ - } \ - swgl_Out##format += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) -#define swgl_commitTextureNearestRepeatRGBA8(s, p, tile_repeat, uv_repeat, \ - uv_rect) \ - swgl_commitTextureNearestRepeat(RGBA8, s, p, tile_repeat, uv_repeat, \ - NoColor()) -#define swgl_commitTextureNearestRepeatColorRGBA8(s, p, tile_repeat, \ - uv_repeat, uv_rect, color) \ - swgl_commitTextureNearestRepeat(RGBA8, s, p, tile_repeat, uv_repeat, color) - -// Commit an entire span of texture with filtering determined by sampler state. -#define swgl_commitTexture(format, s, ...) \ - do { \ - if (s->filter == TextureFilter::LINEAR) { \ - swgl_commitTextureLinear##format(s, __VA_ARGS__); \ - } else { \ - swgl_commitTextureNearest##format(s, __VA_ARGS__); \ - } \ - } while (0) -#define swgl_commitTextureRGBA8(...) swgl_commitTexture(RGBA8, __VA_ARGS__) -#define swgl_commitTextureColorRGBA8(...) \ - swgl_commitTexture(ColorRGBA8, __VA_ARGS__) -#define swgl_commitTextureRepeatRGBA8(...) \ - swgl_commitTexture(RepeatRGBA8, __VA_ARGS__) -#define swgl_commitTextureRepeatColorRGBA8(...) \ - swgl_commitTexture(RepeatColorRGBA8, __VA_ARGS__) - -// Commit an entire span of a separable pass of a Gaussian blur that falls -// within the given radius scaled by supplied coefficients, clamped to uv_rect -// bounds. -template <bool BLEND, typename S, typename P> -static int blendGaussianBlur(S sampler, vec2 uv, const vec4_scalar& uv_rect, - P* buf, int span, bool hori, int radius, - vec2_scalar coeffs) { - if (!matchTextureFormat(sampler, buf)) { - return 0; - } - vec2_scalar size = {float(sampler->width), float(sampler->height)}; - ivec2_scalar curUV = make_ivec2(force_scalar(uv) * size); - ivec4_scalar bounds = make_ivec4(uv_rect * make_vec4(size, size)); - int startX = curUV.x; - int endX = min(bounds.z, curUV.x + span); - if (hori) { - for (; curUV.x + swgl_StepSize <= endX; - buf += swgl_StepSize, curUV.x += swgl_StepSize) { - commit_blend_span<BLEND>( - buf, gaussianBlurHorizontal<P>(sampler, curUV, bounds.x, bounds.z, - radius, coeffs.x, coeffs.y)); - } - } else { - for (; curUV.x + swgl_StepSize <= endX; - buf += swgl_StepSize, curUV.x += swgl_StepSize) { - commit_blend_span<BLEND>( - buf, gaussianBlurVertical<P>(sampler, curUV, bounds.y, bounds.w, - radius, coeffs.x, coeffs.y)); - } - } - return curUV.x - startX; -} - -#define swgl_commitGaussianBlur(format, s, p, uv_rect, hori, radius, coeffs) \ - do { \ - int drawn = 0; \ - if (blend_key) { \ - drawn = blendGaussianBlur<true>(s, p, uv_rect, swgl_Out##format, \ - swgl_SpanLength, hori, radius, coeffs); \ - } else { \ - drawn = blendGaussianBlur<false>(s, p, uv_rect, swgl_Out##format, \ - swgl_SpanLength, hori, radius, coeffs); \ - } \ - swgl_Out##format += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) -#define swgl_commitGaussianBlurRGBA8(s, p, uv_rect, hori, radius, coeffs) \ - swgl_commitGaussianBlur(RGBA8, s, p, uv_rect, hori, radius, coeffs) -#define swgl_commitGaussianBlurR8(s, p, uv_rect, hori, radius, coeffs) \ - swgl_commitGaussianBlur(R8, s, p, uv_rect, hori, radius, coeffs) - -// Convert and pack planar YUV samples to RGB output using a color space -static ALWAYS_INLINE PackedRGBA8 convertYUV(int colorSpace, U16 y, U16 u, - U16 v) { - auto yy = V8<int16_t>(zip(y, y)); - auto uv = V8<int16_t>(zip(u, v)); - return yuvMatrix[colorSpace].convert(yy, uv); -} - -// Helper functions to sample from planar YUV textures before converting to RGB -template <typename S0> -static ALWAYS_INLINE PackedRGBA8 sampleYUV(S0 sampler0, ivec2 uv0, - int colorSpace, - UNUSED int rescaleFactor) { - switch (sampler0->format) { - case TextureFormat::RGBA8: { - auto planar = textureLinearPlanarRGBA8(sampler0, uv0); - return convertYUV(colorSpace, highHalf(planar.rg), lowHalf(planar.rg), - lowHalf(planar.ba)); - } - case TextureFormat::YUV422: { - auto planar = textureLinearPlanarYUV422(sampler0, uv0); - return convertYUV(colorSpace, planar.y, planar.u, planar.v); - } - default: - assert(false); - return PackedRGBA8(0); - } -} - -template <bool BLEND, typename S0, typename P, typename C = NoColor> -static int blendYUV(P* buf, int span, S0 sampler0, vec2 uv0, - const vec4_scalar& uv_rect0, int colorSpace, - int rescaleFactor, C color = C()) { - if (!swgl_isTextureLinear(sampler0)) { - return 0; - } - LINEAR_QUANTIZE_UV(sampler0, uv0, uv_step0, uv_rect0, min_uv0, max_uv0); - auto c = packColor(buf, color); - auto* end = buf + span; - for (; buf < end; buf += swgl_StepSize, uv0 += uv_step0) { - commit_blend_span<BLEND>( - buf, applyColor(sampleYUV(sampler0, ivec2(clamp(uv0, min_uv0, max_uv0)), - colorSpace, rescaleFactor), - c)); - } - return span; -} - -template <typename S0, typename S1> -static ALWAYS_INLINE PackedRGBA8 sampleYUV(S0 sampler0, ivec2 uv0, S1 sampler1, - ivec2 uv1, int colorSpace, - UNUSED int rescaleFactor) { - switch (sampler1->format) { - case TextureFormat::RG8: { - assert(sampler0->format == TextureFormat::R8); - auto y = textureLinearUnpackedR8(sampler0, uv0); - auto planar = textureLinearPlanarRG8(sampler1, uv1); - return convertYUV(colorSpace, y, lowHalf(planar.rg), highHalf(planar.rg)); - } - case TextureFormat::RGBA8: { - assert(sampler0->format == TextureFormat::R8); - auto y = textureLinearUnpackedR8(sampler0, uv0); - auto planar = textureLinearPlanarRGBA8(sampler1, uv1); - return convertYUV(colorSpace, y, lowHalf(planar.ba), highHalf(planar.rg)); - } - default: - assert(false); - return PackedRGBA8(0); - } -} - -template <bool BLEND, typename S0, typename S1, typename P, - typename C = NoColor> -static int blendYUV(P* buf, int span, S0 sampler0, vec2 uv0, - const vec4_scalar& uv_rect0, S1 sampler1, vec2 uv1, - const vec4_scalar& uv_rect1, int colorSpace, - int rescaleFactor, C color = C()) { - if (!swgl_isTextureLinear(sampler0) || !swgl_isTextureLinear(sampler1)) { - return 0; - } - LINEAR_QUANTIZE_UV(sampler0, uv0, uv_step0, uv_rect0, min_uv0, max_uv0); - LINEAR_QUANTIZE_UV(sampler1, uv1, uv_step1, uv_rect1, min_uv1, max_uv1); - auto c = packColor(buf, color); - auto* end = buf + span; - for (; buf < end; buf += swgl_StepSize, uv0 += uv_step0, uv1 += uv_step1) { - commit_blend_span<BLEND>( - buf, applyColor(sampleYUV(sampler0, ivec2(clamp(uv0, min_uv0, max_uv0)), - sampler1, ivec2(clamp(uv1, min_uv1, max_uv1)), - colorSpace, rescaleFactor), - c)); - } - return span; -} - -template <typename S0, typename S1, typename S2> -static ALWAYS_INLINE PackedRGBA8 sampleYUV(S0 sampler0, ivec2 uv0, S1 sampler1, - ivec2 uv1, S2 sampler2, ivec2 uv2, - int colorSpace, int rescaleFactor) { - assert(sampler0->format == sampler1->format && - sampler0->format == sampler2->format); - switch (sampler0->format) { - case TextureFormat::R8: { - auto y = textureLinearUnpackedR8(sampler0, uv0); - auto u = textureLinearUnpackedR8(sampler1, uv1); - auto v = textureLinearUnpackedR8(sampler2, uv2); - return convertYUV(colorSpace, y, u, v); - } - case TextureFormat::R16: { - // The rescaling factor represents how many bits to add to renormalize the - // texture to 16 bits, and so the color depth is actually 16 minus the - // rescaling factor. - // Need to right shift the sample by the amount of bits over 8 it - // occupies. On output from textureLinearUnpackedR16, we have lost 1 bit - // of precision at the low end already, hence 1 is subtracted from the - // color depth. - int colorDepth = 16 - rescaleFactor; - int rescaleBits = (colorDepth - 1) - 8; - auto y = textureLinearUnpackedR16(sampler0, uv0) >> rescaleBits; - auto u = textureLinearUnpackedR16(sampler1, uv1) >> rescaleBits; - auto v = textureLinearUnpackedR16(sampler2, uv2) >> rescaleBits; - return convertYUV(colorSpace, U16(y), U16(u), U16(v)); - } - default: - assert(false); - return PackedRGBA8(0); - } -} - -// Fallback helper for when we can't specifically accelerate YUV with -// composition. -template <bool BLEND, typename S0, typename S1, typename S2, typename P, - typename C> -static void blendYUVFallback(P* buf, int span, S0 sampler0, vec2 uv0, - vec2_scalar uv_step0, vec2_scalar min_uv0, - vec2_scalar max_uv0, S1 sampler1, vec2 uv1, - vec2_scalar uv_step1, vec2_scalar min_uv1, - vec2_scalar max_uv1, S2 sampler2, vec2 uv2, - vec2_scalar uv_step2, vec2_scalar min_uv2, - vec2_scalar max_uv2, int colorSpace, - int rescaleFactor, C color) { - for (auto* end = buf + span; buf < end; buf += swgl_StepSize, uv0 += uv_step0, - uv1 += uv_step1, uv2 += uv_step2) { - commit_blend_span<BLEND>( - buf, applyColor(sampleYUV(sampler0, ivec2(clamp(uv0, min_uv0, max_uv0)), - sampler1, ivec2(clamp(uv1, min_uv1, max_uv1)), - sampler2, ivec2(clamp(uv2, min_uv2, max_uv2)), - colorSpace, rescaleFactor), - color)); - } -} - -template <bool BLEND, typename S0, typename S1, typename S2, typename P, - typename C = NoColor> -static int blendYUV(P* buf, int span, S0 sampler0, vec2 uv0, - const vec4_scalar& uv_rect0, S1 sampler1, vec2 uv1, - const vec4_scalar& uv_rect1, S2 sampler2, vec2 uv2, - const vec4_scalar& uv_rect2, int colorSpace, - int rescaleFactor, C color = C()) { - if (!swgl_isTextureLinear(sampler0) || !swgl_isTextureLinear(sampler1) || - !swgl_isTextureLinear(sampler2)) { - return 0; - } - LINEAR_QUANTIZE_UV(sampler0, uv0, uv_step0, uv_rect0, min_uv0, max_uv0); - LINEAR_QUANTIZE_UV(sampler1, uv1, uv_step1, uv_rect1, min_uv1, max_uv1); - LINEAR_QUANTIZE_UV(sampler2, uv2, uv_step2, uv_rect2, min_uv2, max_uv2); - auto c = packColor(buf, color); - blendYUVFallback<BLEND>(buf, span, sampler0, uv0, uv_step0, min_uv0, max_uv0, - sampler1, uv1, uv_step1, min_uv1, max_uv1, sampler2, - uv2, uv_step2, min_uv2, max_uv2, colorSpace, - rescaleFactor, c); - return span; -} - -// A variant of the blendYUV that attempts to reuse the inner loops from the -// CompositeYUV infrastructure. CompositeYUV imposes stricter requirements on -// the source data, which in turn allows it to be much faster than blendYUV. -// At a minimum, we need to ensure that we are outputting to a BGRA8 framebuffer -// and that no color scaling is applied, which we can accomplish via template -// specialization. We need to further validate inside that texture formats -// and dimensions are sane for video and that the video is axis-aligned before -// acceleration can proceed. -template <bool BLEND> -static int blendYUV(uint32_t* buf, int span, sampler2DRect sampler0, vec2 uv0, - const vec4_scalar& uv_rect0, sampler2DRect sampler1, - vec2 uv1, const vec4_scalar& uv_rect1, - sampler2DRect sampler2, vec2 uv2, - const vec4_scalar& uv_rect2, int colorSpace, - int rescaleFactor, NoColor noColor = NoColor()) { - if (!swgl_isTextureLinear(sampler0) || !swgl_isTextureLinear(sampler1) || - !swgl_isTextureLinear(sampler2)) { - return 0; - } - LINEAR_QUANTIZE_UV(sampler0, uv0, uv_step0, uv_rect0, min_uv0, max_uv0); - LINEAR_QUANTIZE_UV(sampler1, uv1, uv_step1, uv_rect1, min_uv1, max_uv1); - LINEAR_QUANTIZE_UV(sampler2, uv2, uv_step2, uv_rect2, min_uv2, max_uv2); - auto* end = buf + span; - // CompositeYUV imposes further restrictions on the source textures, such that - // the the Y/U/V samplers must all have a matching format, the U/V samplers - // must have matching sizes and sample coordinates, and there must be no - // change in row across the entire span. - if (sampler0->format == sampler1->format && - sampler1->format == sampler2->format && - sampler1->width == sampler2->width && - sampler1->height == sampler2->height && uv_step0.y == 0 && - uv_step0.x > 0 && uv_step1.y == 0 && uv_step1.x > 0 && - uv_step1 == uv_step2 && uv1.x.x == uv2.x.x && uv1.y.x == uv2.y.x) { - // CompositeYUV does not support a clamp rect, so we must take care to - // advance till we're inside the bounds of the clamp rect. - int outside = min(int(ceil(max((min_uv0.x - uv0.x.x) / uv_step0.x, - (min_uv1.x - uv1.x.x) / uv_step1.x))), - (end - buf) / swgl_StepSize); - if (outside > 0) { - blendYUVFallback<BLEND>( - buf, outside * swgl_StepSize, sampler0, uv0, uv_step0, min_uv0, - max_uv0, sampler1, uv1, uv_step1, min_uv1, max_uv1, sampler2, uv2, - uv_step2, min_uv2, max_uv2, colorSpace, rescaleFactor, noColor); - buf += outside * swgl_StepSize; - uv0.x += outside * uv_step0.x; - uv1.x += outside * uv_step1.x; - uv2.x += outside * uv_step2.x; - } - // Find the amount of chunks inside the clamp rect before we hit the - // maximum. If there are any chunks inside, we can finally dispatch to - // CompositeYUV. - int inside = min(int(min((max_uv0.x - uv0.x.x) / uv_step0.x, - (max_uv1.x - uv1.x.x) / uv_step1.x)), - (end - buf) / swgl_StepSize); - if (inside > 0) { - // We need the color depth, which is relative to the texture format and - // rescale factor. - int colorDepth = - (sampler0->format == TextureFormat::R16 ? 16 : 8) - rescaleFactor; - // Finally, call the inner loop of CompositeYUV. - linear_row_yuv<BLEND>( - buf, inside * swgl_StepSize, sampler0, force_scalar(uv0), - uv_step0.x / swgl_StepSize, sampler1, sampler2, force_scalar(uv1), - uv_step1.x / swgl_StepSize, colorDepth, yuvMatrix[colorSpace]); - // Now that we're done, advance past the processed inside portion. - buf += inside * swgl_StepSize; - uv0.x += inside * uv_step0.x; - uv1.x += inside * uv_step1.x; - uv2.x += inside * uv_step2.x; - } - } - // We either got here because we have some samples outside the clamp rect, or - // because some of the preconditions were not satisfied. Process whatever is - // left of the span. - blendYUVFallback<BLEND>(buf, end - buf, sampler0, uv0, uv_step0, min_uv0, - max_uv0, sampler1, uv1, uv_step1, min_uv1, max_uv1, - sampler2, uv2, uv_step2, min_uv2, max_uv2, colorSpace, - rescaleFactor, noColor); - return span; -} - -// Commit a single chunk of a YUV surface represented by multiple planar -// textures. This requires a color space specifier selecting how to convert -// from YUV to RGB output. In the case of HDR formats, a rescaling factor -// selects how many bits of precision must be utilized on conversion. See the -// sampleYUV dispatcher functions for the various supported plane -// configurations this intrinsic accepts. -#define swgl_commitTextureLinearYUV(...) \ - do { \ - int drawn = 0; \ - if (blend_key) { \ - drawn = blendYUV<true>(swgl_OutRGBA8, swgl_SpanLength, __VA_ARGS__); \ - } else { \ - drawn = blendYUV<false>(swgl_OutRGBA8, swgl_SpanLength, __VA_ARGS__); \ - } \ - swgl_OutRGBA8 += drawn; \ - swgl_SpanLength -= drawn; \ - } while (0) - -// Commit a single chunk of a YUV surface scaled by a color. -#define swgl_commitTextureLinearColorYUV(...) \ - swgl_commitTextureLinearYUV(__VA_ARGS__) - -// Each gradient stops entry is a pair of RGBA32F start color and end step. -struct GradientStops { - Float startColor; - union { - Float stepColor; - vec4_scalar stepData; - }; - - // Whether this gradient entry can be merged with an adjacent entry. The - // step will be equal with the adjacent step if and only if they can be - // merged, or rather, that the stops are actually part of a single larger - // gradient. - bool can_merge(const GradientStops& next) const { - return stepData == next.stepData; - } - - // Get the interpolated color within the entry based on the offset from its - // start. - Float interpolate(float offset) const { - return startColor + stepColor * offset; - } - - // Get the end color of the entry where interpolation stops. - Float end_color() const { return startColor + stepColor; } -}; - -// Checks if a gradient table of the specified size exists at the UV coords of -// the address within an RGBA32F texture. If so, a linear address within the -// texture is returned that may be used to sample the gradient table later. If -// the address doesn't describe a valid gradient, then a negative value is -// returned. -static inline int swgl_validateGradient(sampler2D sampler, ivec2_scalar address, - int entries) { - return sampler->format == TextureFormat::RGBA32F && address.y >= 0 && - address.y < int(sampler->height) && address.x >= 0 && - address.x < int(sampler->width) && entries > 0 && - address.x + - int(sizeof(GradientStops) / sizeof(Float)) * entries <= - int(sampler->width) - ? address.y * sampler->stride + address.x * 4 - : -1; -} - -static inline WideRGBA8 sampleGradient(sampler2D sampler, int address, - Float entry) { - assert(sampler->format == TextureFormat::RGBA32F); - assert(address >= 0 && address < int(sampler->height * sampler->stride)); - // Get the integer portion of the entry index to find the entry colors. - I32 index = cast(entry); - // Use the fractional portion of the entry index to control blending between - // entry colors. - Float offset = entry - cast(index); - // Every entry is a pair of colors blended by the fractional offset. - assert(test_all(index >= 0 && - index * int(sizeof(GradientStops) / sizeof(Float)) < - int(sampler->width))); - GradientStops* stops = (GradientStops*)&sampler->buf[address]; - // Blend between the colors for each SIMD lane, then pack them to RGBA8 - // result. Since the layout of the RGBA8 framebuffer is actually BGRA while - // the gradient table has RGBA colors, swizzling is required. - return combine( - packRGBA8(round_pixel(stops[index.x].interpolate(offset.x).zyxw), - round_pixel(stops[index.y].interpolate(offset.y).zyxw)), - packRGBA8(round_pixel(stops[index.z].interpolate(offset.z).zyxw), - round_pixel(stops[index.w].interpolate(offset.w).zyxw))); -} - -// Samples a gradient entry from the gradient at the provided linearized -// address. The integer portion of the entry index is used to find the entry -// within the table whereas the fractional portion is used to blend between -// adjacent table entries. -#define swgl_commitGradientRGBA8(sampler, address, entry) \ - swgl_commitChunk(RGBA8, sampleGradient(sampler, address, entry)) - -// Variant that allows specifying a color multiplier of the gradient result. -#define swgl_commitGradientColorRGBA8(sampler, address, entry, color) \ - swgl_commitChunk(RGBA8, applyColor(sampleGradient(sampler, address, entry), \ - packColor(swgl_OutRGBA, color))) - -// Samples an entire span of a linear gradient by crawling the gradient table -// and looking for consecutive stops that can be merged into a single larger -// gradient, then interpolating between those larger gradients within the span. -template <bool BLEND> -static bool commitLinearGradient(sampler2D sampler, int address, float size, - bool repeat, Float offset, uint32_t* buf, - int span) { - assert(sampler->format == TextureFormat::RGBA32F); - assert(address >= 0 && address < int(sampler->height * sampler->stride)); - GradientStops* stops = (GradientStops*)&sampler->buf[address]; - // Get the chunk delta from the difference in offset steps. This represents - // how far within the gradient table we advance for every step in output, - // normalized to gradient table size. - float delta = (offset.y - offset.x) * 4.0f; - if (!isfinite(delta)) { - return false; - } - for (; span > 0;) { - // If repeat is desired, we need to limit the offset to a fractional value. - if (repeat) { - offset = fract(offset); - } - // Try to process as many chunks as are within the span if possible. - float chunks = 0.25f * span; - // To properly handle both clamping and repeating of the table offset, we - // need to ensure we don't run past the 0 and 1 points. Here we compute the - // intercept points depending on whether advancing forwards or backwards in - // the gradient table to ensure the chunk count is limited by the amount - // before intersection. If there is no delta, then we compute no intercept. - float startEntry; - int minIndex, maxIndex; - if (offset.x < 0) { - // If we're below the gradient table, use the first color stop. We can - // only intercept the table if walking forward. - startEntry = 0; - minIndex = int(startEntry); - maxIndex = minIndex; - if (delta > 0) { - chunks = min(chunks, -offset.x / delta); - } - } else if (offset.x < 1) { - // Otherwise, we're inside the gradient table. Depending on the direction - // we're walking the the table, we may intersect either the 0 or 1 offset. - // Compute the start entry based on our initial offset, and compute the - // end entry based on the available chunks limited by intercepts. Clamp - // them into the valid range of the table. - startEntry = 1.0f + offset.x * size; - if (delta < 0) { - chunks = min(chunks, -offset.x / delta); - } else if (delta > 0) { - chunks = min(chunks, (1 - offset.x) / delta); - } - float endEntry = clamp(1.0f + (offset.x + delta * int(chunks)) * size, - 0.0f, 1.0f + size); - // Now that we know the range of entries we need to sample, we want to - // find the largest possible merged gradient within that range. Depending - // on which direction we are advancing in the table, we either walk up or - // down the table trying to merge the current entry with the adjacent - // entry. We finally limit the chunks to only sample from this merged - // gradient. - minIndex = int(startEntry); - maxIndex = minIndex; - if (delta > 0) { - while (maxIndex + 1 < endEntry && - stops[maxIndex].can_merge(stops[maxIndex + 1])) { - maxIndex++; - } - chunks = min(chunks, (maxIndex + 1 - startEntry) / (delta * size)); - } else if (delta < 0) { - while (minIndex - 1 > endEntry && - stops[minIndex - 1].can_merge(stops[minIndex])) { - minIndex--; - } - chunks = min(chunks, (minIndex - startEntry) / (delta * size)); - } - } else { - // If we're above the gradient table, use the last color stop. We can - // only intercept the table if walking backward. - startEntry = 1.0f + size; - minIndex = int(startEntry); - maxIndex = minIndex; - if (delta < 0) { - chunks = min(chunks, (1 - offset.x) / delta); - } - } - // If there are any amount of whole chunks of a merged gradient found, - // then we want to process that as a single gradient span with the start - // and end colors from the min and max entries. - if (chunks >= 1.0f) { - int inside = int(chunks); - // Sample the start color from the min entry and the end color from the - // max entry of the merged gradient. These are scaled to a range of - // 0..0xFF00, as that is the largest shifted value that can fit in a U16. - // Since we are only doing addition with the step value, we can still - // represent negative step values without having to use an explicit sign - // bit, as the result will still come out the same, allowing us to gain an - // extra bit of precision. We will later shift these into 8 bit output - // range while committing the span, but stepping with higher precision to - // avoid banding. We convert from RGBA to BGRA here to avoid doing this in - // the inner loop. - auto minColorF = stops[minIndex].startColor.zyxw * float(0xFF00); - auto maxColorF = stops[maxIndex].end_color().zyxw * float(0xFF00); - // Get the color range of the merged gradient, normalized to its size. - auto colorRangeF = - (maxColorF - minColorF) * (1.0f / (maxIndex + 1 - minIndex)); - // Compute the actual starting color of the current start offset within - // the merged gradient. The value 0.5 is added to the low bits (0x80) so - // that the color will effective round to the nearest increment below. - auto colorF = - minColorF + colorRangeF * (startEntry - minIndex) + float(0x80); - // Compute the portion of the color range that we advance on each chunk. - Float deltaColorF = colorRangeF * (delta * size); - // Quantize the color delta and current color. These have already been - // scaled to the 0..0xFF00 range, so we just need to round them to U16. - auto deltaColor = repeat4(CONVERT(round_pixel(deltaColorF, 1), U16)); - auto color = - combine(CONVERT(round_pixel(colorF, 1), U16), - CONVERT(round_pixel(colorF + deltaColorF * 0.25f, 1), U16), - CONVERT(round_pixel(colorF + deltaColorF * 0.5f, 1), U16), - CONVERT(round_pixel(colorF + deltaColorF * 0.75f, 1), U16)); - // Finally, step the current color through the output chunks, shifting - // it into 8 bit range and outputting as we go. - for (auto* end = buf + inside * 4; buf < end; buf += 4) { - commit_blend_span<BLEND>(buf, bit_cast<WideRGBA8>(color >> 8)); - color += deltaColor; - } - // Deduct the number of chunks inside the gradient from the remaining - // overall span. If we exhausted the span, bail out. - span -= inside * 4; - if (span <= 0) { - break; - } - // Otherwise, assume we're in a transitional section of the gradient that - // will probably require per-sample table lookups, so fall through below. - offset += inside * delta; - if (repeat) { - offset = fract(offset); - } - } - // If we get here, there were no whole chunks of a merged gradient found - // that we could process, but we still have a non-zero amount of span left. - // That means we have segments of gradient that begin or end at the current - // entry we're on. For this case, we just fall back to sampleGradient which - // will calculate a table entry for each sample, assuming the samples may - // have different table entries. - Float entry = clamp(offset * size + 1.0f, 0.0f, 1.0f + size); - commit_blend_span<BLEND>(buf, sampleGradient(sampler, address, entry)); - span -= 4; - buf += 4; - offset += delta; - } - return true; -} - -// Commits an entire span of a linear gradient, given the address of a table -// previously resolved with swgl_validateGradient. The size of the inner portion -// of the table is given, assuming the table start and ends with a single entry -// each to deal with clamping. Repeating will be handled if necessary. The -// initial offset within the table is used to designate where to start the span -// and how to step through the gradient table. -#define swgl_commitLinearGradientRGBA8(sampler, address, size, repeat, offset) \ - do { \ - bool drawn = false; \ - if (blend_key) { \ - drawn = \ - commitLinearGradient<true>(sampler, address, size, repeat, offset, \ - swgl_OutRGBA8, swgl_SpanLength); \ - } else { \ - drawn = \ - commitLinearGradient<false>(sampler, address, size, repeat, offset, \ - swgl_OutRGBA8, swgl_SpanLength); \ - } \ - if (drawn) { \ - swgl_OutRGBA8 += swgl_SpanLength; \ - swgl_SpanLength = 0; \ - } \ - } while (0) - -template <bool CLAMP, typename V> -static ALWAYS_INLINE V fastSqrt(V v) { -#if USE_SSE2 || USE_NEON - // Clamp to avoid zero in inversesqrt. - return v * inversesqrt(CLAMP ? max(v, V(1.0e-10f)) : v); -#else - return sqrt(v); -#endif -} - -template <bool CLAMP, typename V> -static ALWAYS_INLINE auto fastLength(V v) { - return fastSqrt<CLAMP>(dot(v, v)); -} - -// Samples an entire span of a radial gradient by crawling the gradient table -// and looking for consecutive stops that can be merged into a single larger -// gradient, then interpolating between those larger gradients within the span -// based on the computed position relative to a radius. -template <bool BLEND> -static bool commitRadialGradient(sampler2D sampler, int address, float size, - bool repeat, vec2 pos, float radius, - uint32_t* buf, int span) { - assert(sampler->format == TextureFormat::RGBA32F); - assert(address >= 0 && address < int(sampler->height * sampler->stride)); - GradientStops* stops = (GradientStops*)&sampler->buf[address]; - // clang-format off - // Given position p, delta d, and radius r, we need to repeatedly solve the - // following quadratic for the pixel offset t: - // length(p + t*d) = r - // (px + t*dx)^2 + (py + t*dy)^2 = r^2 - // Rearranged into quadratic equation form (t^2*a + t*b + c = 0) this is: - // t^2*(dx^2+dy^2) + t*2*(dx*px+dy*py) + (px^2+py^2-r^2) = 0 - // t^2*d.d + t*2*d.p + (p.p-r^2) = 0 - // The solution of the quadratic formula t=(-b+-sqrt(b^2-4ac))/2a reduces to: - // t = -d.p/d.d +- sqrt((d.p/d.d)^2 - (p.p-r^2)/d.d) - // Note that d.p, d.d, p.p, and r^2 are constant across the gradient, and so - // we cache them below for faster computation. - // - // The quadratic has two solutions, representing the span intersecting the - // given radius of gradient, which can occur at two offsets. If there is only - // one solution (where b^2-4ac = 0), this represents the point at which the - // span runs tangent to the radius. This middle point is significant in that - // before it, we walk down the gradient ramp, and after it, we walk up the - // ramp. - // clang-format on - vec2_scalar pos0 = {pos.x.x, pos.y.x}; - vec2_scalar delta = {pos.x.y - pos.x.x, pos.y.y - pos.y.x}; - float deltaDelta = dot(delta, delta); - if (!isfinite(deltaDelta) || !isfinite(radius)) { - return false; - } - float invDelta, middleT, middleB; - if (deltaDelta > 0) { - invDelta = 1.0f / deltaDelta; - middleT = -dot(delta, pos0) * invDelta; - middleB = middleT * middleT - dot(pos0, pos0) * invDelta; - } else { - // If position is invariant, just set the coefficients so the quadratic - // always reduces to the end of the span. - invDelta = 0.0f; - middleT = float(span); - middleB = 0.0f; - } - // We only want search for merged gradients up to the minimum of either the - // mid-point or the span length. Cache those offsets here as they don't vary - // in the inner loop. - Float middleEndRadius = fastLength<true>( - pos0 + delta * (Float){middleT, float(span), 0.0f, 0.0f}); - float middleRadius = span < middleT ? middleEndRadius.y : middleEndRadius.x; - float endRadius = middleEndRadius.y; - // Convert delta to change in position per chunk. - delta *= 4; - deltaDelta *= 4 * 4; - // clang-format off - // Given current position p and delta d, we reduce: - // length(p) = sqrt(dot(p,p)) = dot(p,p) * invsqrt(dot(p,p)) - // where dot(p+d,p+d) can be accumulated as: - // (x+dx)^2+(y+dy)^2 = (x^2+y^2) + 2(x*dx+y*dy) + (dx^2+dy^2) - // = p.p + 2p.d + d.d - // Since p increases by d every loop iteration, p.d increases by d.d, and thus - // we can accumulate d.d to calculate 2p.d, then allowing us to get the next - // dot-product by adding it to dot-product p.p of the prior iteration. This - // saves us some multiplications and an expensive sqrt inside the inner loop. - // clang-format on - Float dotPos = dot(pos, pos); - Float dotPosDelta = 2.0f * dot(pos, delta) + deltaDelta; - float deltaDelta2 = 2.0f * deltaDelta; - for (int t = 0; t < span;) { - // Compute the gradient table offset from the current position. - Float offset = fastSqrt<true>(dotPos) - radius; - float startRadius = radius; - // If repeat is desired, we need to limit the offset to a fractional value. - if (repeat) { - // The non-repeating radius at which the gradient table actually starts, - // radius + floor(offset) = radius + (offset - fract(offset)). - startRadius += offset.x; - offset = fract(offset); - startRadius -= offset.x; - } - // We need to find the min/max index in the table of the gradient we want to - // use as well as the intercept point where we leave this gradient. - float intercept = -1; - int minIndex = 0; - int maxIndex = int(1.0f + size); - if (offset.x < 0) { - // If inside the inner radius of the gradient table, then use the first - // stop. Set the intercept to advance forward to the start of the gradient - // table. - maxIndex = minIndex; - if (t >= middleT) { - intercept = radius; - } - } else if (offset.x < 1) { - // Otherwise, we're inside the valid part of the gradient table. - minIndex = int(1.0f + offset.x * size); - maxIndex = minIndex; - // Find the offset in the gradient that corresponds to the search limit. - // We only search up to the minimum of either the mid-point or the span - // length. Get the table index that corresponds to this offset, clamped so - // that we avoid hitting the beginning (0) or end (1 + size) of the table. - float searchOffset = - (t >= middleT ? endRadius : middleRadius) - startRadius; - int searchIndex = int(clamp(1.0f + size * searchOffset, 1.0f, size)); - // If we are past the mid-point, walk up the gradient table trying to - // merge stops. If we're below the mid-point, we need to walk down the - // table. We note the table index at which we need to look for an - // intercept to determine a valid span. - if (t >= middleT) { - while (maxIndex + 1 <= searchIndex && - stops[maxIndex].can_merge(stops[maxIndex + 1])) { - maxIndex++; - } - intercept = maxIndex + 1; - } else { - while (minIndex - 1 >= searchIndex && - stops[minIndex - 1].can_merge(stops[minIndex])) { - minIndex--; - } - intercept = minIndex; - } - // Convert from a table index into units of radius from the center of the - // gradient. - intercept = clamp((intercept - 1.0f) / size, 0.0f, 1.0f) + startRadius; - } else { - // If outside the outer radius of the gradient table, then use the last - // stop. Set the intercept to advance toward the valid part of the - // gradient table if going in, or just run to the end of the span if going - // away from the gradient. - minIndex = maxIndex; - if (t < middleT) { - intercept = radius + 1; - } - } - // Solve the quadratic for t to find where the merged gradient ends. If no - // intercept is found, just go to the middle or end of the span. - float endT = t >= middleT ? span : min(span, int(middleT)); - if (intercept >= 0) { - float b = middleB + intercept * intercept * invDelta; - if (b > 0) { - b = fastSqrt<false>(b); - endT = min(endT, t >= middleT ? middleT + b : middleT - b); - } - } - // Figure out how many chunks are actually inside the merged gradient. - if (t + 4.0f <= endT) { - int inside = int(endT - t) & ~3; - // Convert start and end colors to BGRA and scale to 0..255 range later. - auto minColorF = stops[minIndex].startColor.zyxw * 255.0f; - auto maxColorF = stops[maxIndex].end_color().zyxw * 255.0f; - // Compute the change in color per change in gradient offset. - auto deltaColorF = - (maxColorF - minColorF) * (size / (maxIndex + 1 - minIndex)); - // Subtract off the color difference of the beginning of the current span - // from the beginning of the gradient. - Float colorF = - minColorF - deltaColorF * (startRadius + (minIndex - 1) / size); - // Finally, walk over the span accumulating the position dot product and - // getting its sqrt as an offset into the color ramp. Since we're already - // in BGRA format and scaled to 255, we just need to round to an integer - // and pack down to pixel format. - for (auto* end = buf + inside; buf < end; buf += 4) { - Float offsetG = fastSqrt<false>(dotPos); - commit_blend_span<BLEND>( - buf, - combine( - packRGBA8(round_pixel(colorF + deltaColorF * offsetG.x, 1), - round_pixel(colorF + deltaColorF * offsetG.y, 1)), - packRGBA8(round_pixel(colorF + deltaColorF * offsetG.z, 1), - round_pixel(colorF + deltaColorF * offsetG.w, 1)))); - dotPos += dotPosDelta; - dotPosDelta += deltaDelta2; - } - // Advance past the portion of gradient we just processed. - t += inside; - // If we hit the end of the span, exit out now. - if (t >= span) { - break; - } - // Otherwise, we are most likely in a transitional section of the gradient - // between stops that will likely require doing per-sample table lookups. - // Rather than having to redo all the searching above to figure that out, - // just assume that to be the case and fall through below to doing the - // table lookups to hopefully avoid an iteration. - offset = fastSqrt<true>(dotPos) - radius; - if (repeat) { - offset = fract(offset); - } - } - // If we got here, that means we still have span left to process but did not - // have any whole chunks that fell within a merged gradient. Just fall back - // to doing a table lookup for each sample. - Float entry = clamp(offset * size + 1.0f, 0.0f, 1.0f + size); - commit_blend_span<BLEND>(buf, sampleGradient(sampler, address, entry)); - buf += 4; - t += 4; - dotPos += dotPosDelta; - dotPosDelta += deltaDelta2; - } - return true; -} - -// Commits an entire span of a radial gradient similar to -// swglcommitLinearGradient, but given a varying 2D position scaled to -// gradient-space and a radius at which the distance from the origin maps to the -// start of the gradient table. -#define swgl_commitRadialGradientRGBA8(sampler, address, size, repeat, pos, \ - radius) \ - do { \ - bool drawn = false; \ - if (blend_key) { \ - drawn = \ - commitRadialGradient<true>(sampler, address, size, repeat, pos, \ - radius, swgl_OutRGBA8, swgl_SpanLength); \ - } else { \ - drawn = \ - commitRadialGradient<false>(sampler, address, size, repeat, pos, \ - radius, swgl_OutRGBA8, swgl_SpanLength); \ - } \ - if (drawn) { \ - swgl_OutRGBA8 += swgl_SpanLength; \ - swgl_SpanLength = 0; \ - } \ - } while (0) - -// Extension to set a clip mask image to be sampled during blending. The offset -// specifies the positioning of the clip mask image relative to the viewport -// origin. The bounding box specifies the rectangle relative to the clip mask's -// origin that constrains sampling within the clip mask. Blending must be -// enabled for this to work. -static sampler2D swgl_ClipMask = nullptr; -static IntPoint swgl_ClipMaskOffset = {0, 0}; -static IntRect swgl_ClipMaskBounds = {0, 0, 0, 0}; -#define swgl_clipMask(mask, offset, bb_origin, bb_size) \ - do { \ - if (bb_size != vec2_scalar(0.0f, 0.0f)) { \ - swgl_ClipFlags |= SWGL_CLIP_FLAG_MASK; \ - swgl_ClipMask = mask; \ - swgl_ClipMaskOffset = make_ivec2(offset); \ - swgl_ClipMaskBounds = \ - IntRect(make_ivec2(bb_origin), make_ivec2(bb_size)); \ - } \ - } while (0) - -// Extension to enable anti-aliasing for the given edges of a quad. -// Blending must be enable for this to work. -static int swgl_AAEdgeMask = 0; - -static ALWAYS_INLINE int calcAAEdgeMask(bool on) { return on ? 0xF : 0; } -static ALWAYS_INLINE int calcAAEdgeMask(int mask) { return mask; } -static ALWAYS_INLINE int calcAAEdgeMask(bvec4_scalar mask) { - return (mask.x ? 1 : 0) | (mask.y ? 2 : 0) | (mask.z ? 4 : 0) | - (mask.w ? 8 : 0); -} - -#define swgl_antiAlias(edges) \ - do { \ - swgl_AAEdgeMask = calcAAEdgeMask(edges); \ - if (swgl_AAEdgeMask) { \ - swgl_ClipFlags |= SWGL_CLIP_FLAG_AA; \ - } \ - } while (0) - -#define swgl_blendDropShadow(color) \ - do { \ - swgl_ClipFlags |= SWGL_CLIP_FLAG_BLEND_OVERRIDE; \ - swgl_BlendOverride = BLEND_KEY(SWGL_BLEND_DROP_SHADOW); \ - swgl_BlendColorRGBA8 = packColor<uint32_t>(color); \ - } while (0) - -#define swgl_blendSubpixelText(color) \ - do { \ - swgl_ClipFlags |= SWGL_CLIP_FLAG_BLEND_OVERRIDE; \ - swgl_BlendOverride = BLEND_KEY(SWGL_BLEND_SUBPIXEL_TEXT); \ - swgl_BlendColorRGBA8 = packColor<uint32_t>(color); \ - swgl_BlendAlphaRGBA8 = alphas(swgl_BlendColorRGBA8); \ - } while (0) - -// Dispatch helper used by the GLSL translator to swgl_drawSpan functions. -// The number of pixels committed is tracked by checking for the difference in -// swgl_SpanLength. Any varying interpolants used will be advanced past the -// committed part of the span in case the fragment shader must be executed for -// any remaining pixels that were not committed by the span shader. -#define DISPATCH_DRAW_SPAN(self, format) \ - do { \ - int total = self->swgl_SpanLength; \ - self->swgl_drawSpan##format(); \ - int drawn = total - self->swgl_SpanLength; \ - if (drawn) self->step_interp_inputs(drawn); \ - return drawn; \ - } while (0) |