Auto merge of #13187 - glennw:wr-update-ref, r=pcwalton

Update WR (various reftest fixes).

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4 files changed, 54 insertions, 51 deletions

diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index b84d1af3d16..535616b76f4 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -2592,7 +2592,7 @@ dependencies = [
 [[package]]
 name = "webrender"
 version = "0.5.1"
-source = "git+https://github.com/servo/webrender#b2cca277407b59c4c3b8122f36b64bd81f83a4dc"
+source = "git+https://github.com/servo/webrender#f82fad77b938e339be7ccfc9ba23d2ebd7a72fcb"
 dependencies = [
  "app_units 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bincode 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2617,7 +2617,7 @@ dependencies = [
 [[package]]
 name = "webrender_traits"
 version = "0.5.1"
-source = "git+https://github.com/servo/webrender#b2cca277407b59c4c3b8122f36b64bd81f83a4dc"
+source = "git+https://github.com/servo/webrender#f82fad77b938e339be7ccfc9ba23d2ebd7a72fcb"
 dependencies = [
  "app_units 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index 7418cf12d0d..929c41ba891 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -2452,7 +2452,7 @@ dependencies = [
 [[package]]
 name = "webrender"
 version = "0.5.1"
-source = "git+https://github.com/servo/webrender#b2cca277407b59c4c3b8122f36b64bd81f83a4dc"
+source = "git+https://github.com/servo/webrender#f82fad77b938e339be7ccfc9ba23d2ebd7a72fcb"
 dependencies = [
  "app_units 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "bincode 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2477,7 +2477,7 @@ dependencies = [
 [[package]]
 name = "webrender_traits"
 version = "0.5.1"
-source = "git+https://github.com/servo/webrender#b2cca277407b59c4c3b8122f36b64bd81f83a4dc"
+source = "git+https://github.com/servo/webrender#f82fad77b938e339be7ccfc9ba23d2ebd7a72fcb"
 dependencies = [
  "app_units 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 0.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/resources/shaders/prim_shared.glsl b/resources/shaders/prim_shared.glsl
index 21d6c41e382..820ab47633d 100644
--- a/resources/shaders/prim_shared.glsl
+++ b/resources/shaders/prim_shared.glsl
@@ -30,6 +30,8 @@
 #define MAX_STOPS_PER_ANGLE_GRADIENT 8
 
 #ifdef WR_VERTEX_SHADER
+uniform sampler2D sLayers;
+
 struct Layer {
     mat4 transform;
     mat4 inv_transform;
@@ -45,31 +47,27 @@ layout(std140) uniform Tiles {
     vec4 tiles[WR_MAX_UBO_VECTORS];
 };
 
-layout(std140) uniform Layers {
-    vec4 layers[WR_MAX_UBO_VECTORS];
-};
-
 Layer fetch_layer(int index) {
     Layer layer;
 
-    int offset = index * 13;
+    ivec2 uv = ivec2(0, index);
 
-    layer.transform[0] = layers[offset + 0];
-    layer.transform[1] = layers[offset + 1];
-    layer.transform[2] = layers[offset + 2];
-    layer.transform[3] = layers[offset + 3];
+    layer.transform[0] = texelFetchOffset(sLayers, uv, 0, ivec2(0, 0));
+    layer.transform[1] = texelFetchOffset(sLayers, uv, 0, ivec2(1, 0));
+    layer.transform[2] = texelFetchOffset(sLayers, uv, 0, ivec2(2, 0));
+    layer.transform[3] = texelFetchOffset(sLayers, uv, 0, ivec2(3, 0));
 
-    layer.inv_transform[0] = layers[offset + 4];
-    layer.inv_transform[1] = layers[offset + 5];
-    layer.inv_transform[2] = layers[offset + 6];
-    layer.inv_transform[3] = layers[offset + 7];
+    layer.inv_transform[0] = texelFetchOffset(sLayers, uv, 0, ivec2(4, 0));
+    layer.inv_transform[1] = texelFetchOffset(sLayers, uv, 0, ivec2(5, 0));
+    layer.inv_transform[2] = texelFetchOffset(sLayers, uv, 0, ivec2(6, 0));
+    layer.inv_transform[3] = texelFetchOffset(sLayers, uv, 0, ivec2(7, 0));
 
-    layer.local_clip_rect = layers[offset + 8];
+    layer.local_clip_rect = texelFetchOffset(sLayers, uv, 0, ivec2(8, 0));
 
-    layer.screen_vertices[0] = layers[offset + 9];
-    layer.screen_vertices[1] = layers[offset + 10];
-    layer.screen_vertices[2] = layers[offset + 11];
-    layer.screen_vertices[3] = layers[offset + 12];
+    layer.screen_vertices[0] = texelFetchOffset(sLayers, uv, 0, ivec2(9, 0));
+    layer.screen_vertices[1] = texelFetchOffset(sLayers, uv, 0, ivec2(10, 0));
+    layer.screen_vertices[2] = texelFetchOffset(sLayers, uv, 0, ivec2(11, 0));
+    layer.screen_vertices[3] = texelFetchOffset(sLayers, uv, 0, ivec2(12, 0));
 
     return layer;
 }
diff --git a/resources/shaders/ps_border.fs.glsl b/resources/shaders/ps_border.fs.glsl
index 9dfeb2d26c2..74881dd34f0 100644
--- a/resources/shaders/ps_border.fs.glsl
+++ b/resources/shaders/ps_border.fs.glsl
@@ -52,36 +52,43 @@ float alpha_for_solid_border_corner(vec2 local_pos,
   return alpha_for_solid_border(distance_from_ref, inner_radius, outer_radius, pixels_per_fragment);
 }
 
-#ifdef WR_FEATURE_TRANSFORM
-
-#else
-vec4 draw_dotted_edge(vec2 position, vec2 edge_size, float pixels_per_fragment) {
-  float two_pixels = 2 * pixels_per_fragment;
+vec4 draw_dotted_edge(vec2 local_pos, vec4 piece_rect, float pixels_per_fragment) {
+  // We don't use pixels_per_fragment here, since it can change along the edge
+  // of a transformed border edge. We want this calculation to be consistent
+  // across the entire edge so that the positioning of the dots stays the same.
+  float two_pixels = 2 * length(fwidth(vLocalPos.xy));
 
   // Circle diameter is stroke width, minus a couple pixels to account for anti-aliasing.
-  float circle_diameter = max(edge_size.x - two_pixels, min(edge_size.x, two_pixels));
+  float circle_diameter = max(piece_rect.z - two_pixels, min(piece_rect.z, two_pixels));
 
-  //// Divide the edge into segments which are the size of the circle diameter.
-  float segments_in_edge = floor(edge_size.y / circle_diameter);
+  // We want to spread the circles across the edge, but keep one circle diameter at the end
+  // reserved for two half-circles which connect to the corners.
+  float edge_available = piece_rect.w - (circle_diameter * 2);
+  float number_of_circles = floor(edge_available / (circle_diameter * 2));
 
-  // Every other segment has a circle.
-  float number_of_circles = floor(segments_in_edge / 2);
-  if (number_of_circles <= 0)
-    return vec4(0, 0, 0, 0);
+  // Here we are initializing the distance from the y coordinate of the center of the circle to
+  // the closest end half-circle.
+  vec2 relative_pos = local_pos - piece_rect.xy;
+  float y_distance = min(relative_pos.y, piece_rect.w - relative_pos.y);
+
+  if (number_of_circles > 0) {
+    // Spread the circles throughout the edge, to distribute the extra space evenly. We want
+    // to ensure that we have at last two pixels of space for each circle so that they aren't
+    // touching.
+    float space_for_each_circle = ceil(max(edge_available / number_of_circles, two_pixels));
 
-  // Spread the circles throughout the edge, to distribute the extra space evenly. We want
-  // to ensure that we have at last two pixels of space for each circle so that they aren't
-  // touching.
-  float space_for_each_circle = ceil(max(edge_size.y / number_of_circles, two_pixels));
+    float first_half_circle_space = circle_diameter;
 
-  // Find the circle index. We adjust the y position here because the first circle is a
-  // half circle at the edge of this border side.
-  float circle_index = floor((position.y + (space_for_each_circle / 2)) / space_for_each_circle);
+    float circle_index = (relative_pos.y - first_half_circle_space) / space_for_each_circle;
+    circle_index = floor(clamp(circle_index, 0, number_of_circles - 1));
 
-  // Find the center of the circle that is closest to our position. We will then calculate
-  // the distance from the edge of the circle.
-  vec2 circle_center = vec2(edge_size.x / 2, circle_index * space_for_each_circle);
-  float distance_from_circle_edge = length(circle_center - position) - (circle_diameter / 2);
+    float circle_y_pos =
+      circle_index * space_for_each_circle + (space_for_each_circle / 2) + circle_diameter;
+    y_distance = min(abs(circle_y_pos - relative_pos.y), y_distance);
+  }
+
+  float distance_from_circle_center = length(vec2(relative_pos.x - (piece_rect.z / 2), y_distance));
+  float distance_from_circle_edge = distance_from_circle_center - (circle_diameter / 2);
 
   // Don't anti-alias if the circle diameter is small to avoid a blur of color.
   if (circle_diameter < two_pixels && distance_from_circle_edge > 0)
@@ -117,22 +124,18 @@ void draw_dotted_border(vec2 local_pos, float distance_from_mix_line) {
     }
     case PST_BOTTOM:
     case PST_TOP: {
-      vec2 piece_relative_position = vLocalPos - vPieceRect.xy;
-      oFragColor = draw_dotted_edge(piece_relative_position.yx, vPieceRect.wz, pixels_per_fragment);
+      oFragColor = draw_dotted_edge(local_pos.yx, vPieceRect.yxwz, pixels_per_fragment);
       break;
     }
     case PST_LEFT:
     case PST_RIGHT:
     {
-      vec2 piece_relative_position = vLocalPos - vPieceRect.xy;
-      oFragColor = draw_dotted_edge(piece_relative_position.xy, vPieceRect.zw, pixels_per_fragment);
+      oFragColor = draw_dotted_edge(local_pos.xy, vPieceRect.xyzw, pixels_per_fragment);
       break;
     }
   }
 }
 
-#endif
-
 vec4 draw_dashed_edge(float position, float border_width, float pixels_per_fragment) {
   // TODO: Investigate exactly what FF does.
   float size = border_width * 3;
@@ -334,6 +337,8 @@ void main(void) {
           draw_dashed_border(local_pos, distance_from_mix_line);
           break;
         case BORDER_STYLE_DOTTED:
+            draw_dotted_border(local_pos, distance_from_mix_line);
+            break;
         case BORDER_STYLE_OUTSET:
         case BORDER_STYLE_INSET:
         case BORDER_STYLE_SOLID: