Auto merge of #25789 - szeged:mmatyas__webgl_fns_clearbuffer, r=jdm

Add support for WebGL2 clear buffer operations

Adds support for the following WebGL2 methods:

- `clearBufferfv`
- `clearBufferiv`
- `clearBufferuiv`
- `clearBufferfi`

See: https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.11

<!-- Please describe your changes on the following line: -->

cc @jdm @zakorgy

Note: While the code itself doesn't depend on any other PRs, some of the tests do require WebGL2 framebuffer/renderbuffer support (#25785).

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes

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10 files changed, 215 insertions, 125 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 3baf44fdca4..187c2cf6e61 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5531,9 +5531,9 @@ dependencies = [
 
 [[package]]
 name = "sparkle"
-version = "0.1.16"
+version = "0.1.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "69ff56f232996280b7ac243ad746194fcd7a008104ffc70f0ed3494d07bc442a"
+checksum = "7574caaf01cfad60fedbb0fde776df021073d3d49426219f0851576590764724"
 dependencies = [
  "gl_generator 0.13.1",
 ]
diff --git a/components/canvas/Cargo.toml b/components/canvas/Cargo.toml
index 0dc4cbe9491..82e34bde036 100644
--- a/components/canvas/Cargo.toml
+++ b/components/canvas/Cargo.toml
@@ -37,7 +37,7 @@ raqote = {git = "https://github.com/jrmuizel/raqote", optional = true}
 time = { version = "0.1.0", optional = true }
 pixels = {path = "../pixels"}
 servo_config = {path = "../config"}
-sparkle = "0.1.16"
+sparkle = "0.1.17"
 webrender = {git = "https://github.com/servo/webrender"}
 webrender_api = {git = "https://github.com/servo/webrender"}
 webrender_traits = {path = "../webrender_traits"}
diff --git a/components/canvas/webgl_thread.rs b/components/canvas/webgl_thread.rs
index 186ac043b38..079928c9d57 100644
--- a/components/canvas/webgl_thread.rs
+++ b/components/canvas/webgl_thread.rs
@@ -1956,6 +1956,18 @@ impl WebGLImpl {
                 offset as isize,
                 size as isize,
             ),
+            WebGLCommand::ClearBufferfv(buffer, draw_buffer, ref value) => {
+                gl.clear_buffer_fv(buffer, draw_buffer, value)
+            },
+            WebGLCommand::ClearBufferiv(buffer, draw_buffer, ref value) => {
+                gl.clear_buffer_iv(buffer, draw_buffer, value)
+            },
+            WebGLCommand::ClearBufferuiv(buffer, draw_buffer, ref value) => {
+                gl.clear_buffer_uiv(buffer, draw_buffer, value)
+            },
+            WebGLCommand::ClearBufferfi(buffer, draw_buffer, depth, stencil) => {
+                gl.clear_buffer_fi(buffer, draw_buffer, depth, stencil)
+            },
         }
 
         // If debug asertions are enabled, then check the error state.
diff --git a/components/canvas_traits/webgl.rs b/components/canvas_traits/webgl.rs
index 6709137b34e..ce409f07594 100644
--- a/components/canvas_traits/webgl.rs
+++ b/components/canvas_traits/webgl.rs
@@ -529,6 +529,10 @@ pub enum WebGLCommand {
     GetSamplerParameterInt(WebGLSamplerId, u32, WebGLSender<i32>),
     BindBufferBase(u32, u32, Option<WebGLBufferId>),
     BindBufferRange(u32, u32, Option<WebGLBufferId>, i64, i64),
+    ClearBufferfv(u32, i32, Vec<f32>),
+    ClearBufferiv(u32, i32, Vec<i32>),
+    ClearBufferuiv(u32, i32, Vec<u32>),
+    ClearBufferfi(u32, i32, f32, i32),
 }
 
 macro_rules! nonzero_type {
diff --git a/components/script/dom/webgl2renderingcontext.rs b/components/script/dom/webgl2renderingcontext.rs
index dfce0f043ab..cc735f36e41 100644
--- a/components/script/dom/webgl2renderingcontext.rs
+++ b/components/script/dom/webgl2renderingcontext.rs
@@ -557,6 +557,52 @@ impl WebGL2RenderingContext {
         let retval = receiver.recv().unwrap();
         Ok(Int32Value(retval))
     }
+
+    fn clearbuffer_array_size(&self, buffer: u32, draw_buffer: i32) -> WebGLResult<usize> {
+        match buffer {
+            constants::COLOR => {
+                if draw_buffer < 0 || draw_buffer as u32 >= self.base.limits().max_draw_buffers {
+                    return Err(InvalidValue);
+                }
+                Ok(4)
+            },
+            constants::DEPTH | constants::STENCIL | constants::DEPTH_STENCIL => {
+                if draw_buffer != 0 {
+                    return Err(InvalidValue);
+                }
+                Ok(1)
+            },
+            _ => unreachable!(),
+        }
+    }
+
+    fn clear_buffer<T: Clone>(
+        &self,
+        buffer: u32,
+        draw_buffer: i32,
+        valid_buffers: &[u32],
+        src_offset: u32,
+        array: Vec<T>,
+        msg: fn(u32, i32, Vec<T>) -> WebGLCommand,
+    ) {
+        if !valid_buffers.contains(&buffer) {
+            return self.base.webgl_error(InvalidEnum);
+        }
+
+        let array_size = handle_potential_webgl_error!(
+            self.base,
+            self.clearbuffer_array_size(buffer, draw_buffer),
+            return
+        );
+        let src_offset = src_offset as usize;
+
+        if array.len() < src_offset + array_size {
+            return self.base.webgl_error(InvalidValue);
+        }
+        let array = array[src_offset..src_offset + array_size].to_vec();
+
+        self.base.send_command(msg(buffer, draw_buffer, array));
+    }
 }
 
 impl WebGL2RenderingContextMethods for WebGL2RenderingContext {
@@ -3365,6 +3411,92 @@ impl WebGL2RenderingContextMethods for WebGL2RenderingContext {
             return
         )
     }
+
+    /// https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.11
+    fn ClearBufferfv(
+        &self,
+        buffer: u32,
+        draw_buffer: i32,
+        values: Float32ArrayOrUnrestrictedFloatSequence,
+        src_offset: u32,
+    ) {
+        let array = match values {
+            Float32ArrayOrUnrestrictedFloatSequence::Float32Array(v) => v.to_vec(),
+            Float32ArrayOrUnrestrictedFloatSequence::UnrestrictedFloatSequence(v) => v,
+        };
+        self.clear_buffer::<f32>(
+            buffer,
+            draw_buffer,
+            &[constants::COLOR, constants::DEPTH],
+            src_offset,
+            array,
+            WebGLCommand::ClearBufferfv,
+        )
+    }
+
+    /// https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.11
+    fn ClearBufferiv(
+        &self,
+        buffer: u32,
+        draw_buffer: i32,
+        values: Int32ArrayOrLongSequence,
+        src_offset: u32,
+    ) {
+        let array = match values {
+            Int32ArrayOrLongSequence::Int32Array(v) => v.to_vec(),
+            Int32ArrayOrLongSequence::LongSequence(v) => v,
+        };
+        self.clear_buffer::<i32>(
+            buffer,
+            draw_buffer,
+            &[constants::COLOR, constants::STENCIL],
+            src_offset,
+            array,
+            WebGLCommand::ClearBufferiv,
+        )
+    }
+
+    /// https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.11
+    fn ClearBufferuiv(
+        &self,
+        buffer: u32,
+        draw_buffer: i32,
+        values: Uint32ArrayOrUnsignedLongSequence,
+        src_offset: u32,
+    ) {
+        let array = match values {
+            Uint32ArrayOrUnsignedLongSequence::Uint32Array(v) => v.to_vec(),
+            Uint32ArrayOrUnsignedLongSequence::UnsignedLongSequence(v) => v,
+        };
+        self.clear_buffer::<u32>(
+            buffer,
+            draw_buffer,
+            &[constants::COLOR],
+            src_offset,
+            array,
+            WebGLCommand::ClearBufferuiv,
+        )
+    }
+
+    /// https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.11
+    fn ClearBufferfi(&self, buffer: u32, draw_buffer: i32, depth: f32, stencil: i32) {
+        if buffer != constants::DEPTH_STENCIL {
+            return self.base.webgl_error(InvalidEnum);
+        }
+
+        handle_potential_webgl_error!(
+            self.base,
+            self.clearbuffer_array_size(buffer, draw_buffer),
+            return
+        );
+
+        self.base.send_command(WebGLCommand::ClearBufferfi(
+            buffer,
+            draw_buffer,
+            depth,
+            stencil,
+        ));
+    }
 }
 
 impl LayoutCanvasWebGLRenderingContextHelpers for LayoutDom<WebGL2RenderingContext> {
diff --git a/components/script/dom/webidls/WebGL2RenderingContext.webidl b/components/script/dom/webidls/WebGL2RenderingContext.webidl
index 859bfaf33c7..23686adb211 100644
--- a/components/script/dom/webidls/WebGL2RenderingContext.webidl
+++ b/components/script/dom/webidls/WebGL2RenderingContext.webidl
@@ -481,14 +481,14 @@ interface mixin WebGL2RenderingContextBase
   /* Multiple Render Targets */
   // void drawBuffers(sequence<GLenum> buffers);
 
-  // void clearBufferfv(GLenum buffer, GLint drawbuffer, Float32List values,
-  //                    optional GLuint srcOffset = 0);
-  // void clearBufferiv(GLenum buffer, GLint drawbuffer, Int32List values,
-  //                    optional GLuint srcOffset = 0);
-  // void clearBufferuiv(GLenum buffer, GLint drawbuffer, Uint32List values,
-  //                     optional GLuint srcOffset = 0);
-
-  // void clearBufferfi(GLenum buffer, GLint drawbuffer, GLfloat depth, GLint stencil);
+  void clearBufferfv(GLenum buffer, GLint drawbuffer, Float32List values,
+                     optional GLuint srcOffset = 0);
+  void clearBufferiv(GLenum buffer, GLint drawbuffer, Int32List values,
+                     optional GLuint srcOffset = 0);
+  void clearBufferuiv(GLenum buffer, GLint drawbuffer, Uint32List values,
+                      optional GLuint srcOffset = 0);
+
+  void clearBufferfi(GLenum buffer, GLint drawbuffer, GLfloat depth, GLint stencil);
 
   /* Query Objects */
   WebGLQuery? createQuery();
diff --git a/tests/wpt/webgl/meta/conformance2/context/methods-2.html.ini b/tests/wpt/webgl/meta/conformance2/context/methods-2.html.ini
index 748a0480e98..4b257a001d7 100644
--- a/tests/wpt/webgl/meta/conformance2/context/methods-2.html.ini
+++ b/tests/wpt/webgl/meta/conformance2/context/methods-2.html.ini
@@ -1,91 +1,4 @@
 [methods-2.html]
-  [WebGL test #11: Property either does not exist or is not a function: compressedTexSubImage3D]
-    expected: FAIL
-
-  [WebGL test #8: Property either does not exist or is not a function: texSubImage3D]
-    expected: FAIL
-
-  [WebGL test #28: Property either does not exist or is not a function: bindVertexArray]
-    expected: FAIL
-
-  [WebGL test #14: Property either does not exist or is not a function: vertexAttribI4iv]
-    expected: FAIL
-
-  [WebGL test #23: Property either does not exist or is not a function: clearBufferfi]
-    expected: FAIL
-
-  [WebGL test #15: Property either does not exist or is not a function: vertexAttribI4ui]
-    expected: FAIL
-
-  [WebGL test #27: Property either does not exist or is not a function: isVertexArray]
-    expected: FAIL
-
-  [WebGL test #20: Property either does not exist or is not a function: clearBufferiv]
-    expected: FAIL
-
-  [WebGL test #22: Property either does not exist or is not a function: clearBufferfv]
-    expected: FAIL
-
-  [WebGL test #6: Property either does not exist or is not a function: texStorage2D]
-    expected: FAIL
-
-  [WebGL test #1: Property either does not exist or is not a function: blitFramebuffer]
-    expected: FAIL
-
-  [WebGL test #13: Property either does not exist or is not a function: vertexAttribI4i]
-    expected: FAIL
-
-  [WebGL test #5: Property either does not exist or is not a function: texImage3D]
-    expected: FAIL
-
-  [WebGL test #21: Property either does not exist or is not a function: clearBufferuiv]
-    expected: FAIL
-
-  [WebGL test #26: Property either does not exist or is not a function: deleteVertexArray]
-    expected: FAIL
-
-  [WebGL test #4: Property either does not exist or is not a function: renderbufferStorageMultisample]
-    expected: FAIL
-
-  [WebGL test #19: Property either does not exist or is not a function: drawBuffers]
-    expected: FAIL
-
-  [WebGL test #10: Property either does not exist or is not a function: compressedTexImage3D]
-    expected: FAIL
-
-  [WebGL test #7: Property either does not exist or is not a function: texStorage3D]
-    expected: FAIL
-
-  [WebGL test #16: Property either does not exist or is not a function: vertexAttribI4uiv]
-    expected: FAIL
-
-  [WebGL test #18: Property either does not exist or is not a function: drawRangeElements]
-    expected: FAIL
-
-  [WebGL test #9: Property either does not exist or is not a function: copyTexSubImage3D]
-    expected: FAIL
-
-  [WebGL test #0: Property either does not exist or is not a function: isContextLost]
-    expected: FAIL
-
-  [WebGL test #17: Property either does not exist or is not a function: vertexAttribIPointer]
-    expected: FAIL
-
-  [WebGL test #24: Property either does not exist or is not a function: getIndexedParameter]
-    expected: FAIL
-
-  [WebGL test #2: Property either does not exist or is not a function: getInternalformatParameter]
-    expected: FAIL
-
-  [WebGL test #25: Property either does not exist or is not a function: createVertexArray]
-    expected: FAIL
-
-  [WebGL test #3: Property either does not exist or is not a function: readBuffer]
-    expected: FAIL
-
-  [WebGL test #12: Property either does not exist or is not a function: getFragDataLocation]
-    expected: FAIL
-
   [WebGL test #16: Property either does not exist or is not a function: vertexAttribI4i]
     expected: FAIL
 
@@ -107,16 +20,13 @@
   [WebGL test #4: Property either does not exist or is not a function: invalidateFramebuffer]
     expected: FAIL
 
-  [WebGL test #30: Property either does not exist or is not a function: isVertexArray]
-    expected: FAIL
-
   [WebGL test #7: Property either does not exist or is not a function: renderbufferStorageMultisample]
     expected: FAIL
 
   [WebGL test #10: Property either does not exist or is not a function: texStorage3D]
     expected: FAIL
 
-  [WebGL test #29: Property either does not exist or is not a function: deleteVertexArray]
+  [WebGL test #1: Property either does not exist or is not a function: blitFramebuffer]
     expected: FAIL
 
   [WebGL test #11: Property either does not exist or is not a function: texSubImage3D]
@@ -125,19 +35,22 @@
   [WebGL test #20: Property either does not exist or is not a function: vertexAttribIPointer]
     expected: FAIL
 
-  [WebGL test #27: Property either does not exist or is not a function: getIndexedParameter]
+  [WebGL test #25: Property either does not exist or is not a function: deleteVertexArray]
     expected: FAIL
 
-  [WebGL test #3: Property either does not exist or is not a function: getInternalformatParameter]
+  [WebGL test #23: Property either does not exist or is not a function: getIndexedParameter]
+    expected: FAIL
+
+  [WebGL test #26: Property either does not exist or is not a function: isVertexArray]
     expected: FAIL
 
-  [WebGL test #23: Property either does not exist or is not a function: clearBufferiv]
+  [WebGL test #3: Property either does not exist or is not a function: getInternalformatParameter]
     expected: FAIL
 
   [WebGL test #21: Property either does not exist or is not a function: drawRangeElements]
     expected: FAIL
 
-  [WebGL test #26: Property either does not exist or is not a function: clearBufferfi]
+  [WebGL test #27: Property either does not exist or is not a function: bindVertexArray]
     expected: FAIL
 
   [WebGL test #13: Property either does not exist or is not a function: compressedTexImage3D]
@@ -152,16 +65,13 @@
   [WebGL test #8: Property either does not exist or is not a function: texImage3D]
     expected: FAIL
 
-  [WebGL test #28: Property either does not exist or is not a function: createVertexArray]
-    expected: FAIL
-
-  [WebGL test #25: Property either does not exist or is not a function: clearBufferfv]
+  [WebGL test #0: Property either does not exist or is not a function: isContextLost]
     expected: FAIL
 
-  [WebGL test #24: Property either does not exist or is not a function: clearBufferuiv]
+  [WebGL test #9: Property either does not exist or is not a function: texStorage2D]
     expected: FAIL
 
-  [WebGL test #9: Property either does not exist or is not a function: texStorage2D]
+  [WebGL test #24: Property either does not exist or is not a function: createVertexArray]
     expected: FAIL
 
   [WebGL test #6: Property either does not exist or is not a function: readBuffer]
@@ -173,6 +83,3 @@
   [WebGL test #14: Property either does not exist or is not a function: compressedTexSubImage3D]
     expected: FAIL
 
-  [WebGL test #31: Property either does not exist or is not a function: bindVertexArray]
-    expected: FAIL
-
diff --git a/tests/wpt/webgl/meta/conformance2/rendering/clear-srgb-color-buffer.html.ini b/tests/wpt/webgl/meta/conformance2/rendering/clear-srgb-color-buffer.html.ini
index afe03f0cc80..219c4ae023b 100644
--- a/tests/wpt/webgl/meta/conformance2/rendering/clear-srgb-color-buffer.html.ini
+++ b/tests/wpt/webgl/meta/conformance2/rendering/clear-srgb-color-buffer.html.ini
@@ -1,11 +1,10 @@
 [clear-srgb-color-buffer.html]
-  expected: ERROR
   [WebGL test #1: Framebuffer incomplete.]
     expected: FAIL
 
-  [WebGL test #3: successfullyParsed should be true (of type boolean). Was undefined (of type undefined).]
+  [WebGL test #2: \nat (0, 0) expected: 124,193,222,255 was 0,0,0,0]
     expected: FAIL
 
-  [WebGL test #2: \nat (0, 0) expected: 124,193,222,255 was 0,0,0,0]
+  [WebGL test #3: \nat (0, 0) expected: 124,193,222,255 was 0,0,0,0]
     expected: FAIL
 
diff --git a/tests/wpt/webgl/meta/conformance2/rendering/clearbuffer-sub-source.html.ini b/tests/wpt/webgl/meta/conformance2/rendering/clearbuffer-sub-source.html.ini
index e5cfaa20221..31919597057 100644
--- a/tests/wpt/webgl/meta/conformance2/rendering/clearbuffer-sub-source.html.ini
+++ b/tests/wpt/webgl/meta/conformance2/rendering/clearbuffer-sub-source.html.ini
@@ -1,8 +1,49 @@
 [clearbuffer-sub-source.html]
-  expected: ERROR
+  [WebGL test #14: getError expected: NO_ERROR. Was INVALID_FRAMEBUFFER_OPERATION : clearBuffer with srcOffset = 2 should succeed]
+    expected: FAIL
+
+  [WebGL test #5: clearBuffer fails to work. Expected: 1,2,3,4, got: 0,0,0,0]
+    expected: FAIL
+
+  [WebGL test #2: getError expected: NO_ERROR. Was INVALID_ENUM : clearBuffer with no srcOffset should succeed]
+    expected: FAIL
+
+  [WebGL test #11: clearBuffer fails to work. Expected: 1,2,3,4, got: 0,0,0,0]
+    expected: FAIL
+
+  [WebGL test #13: clearBuffer fails to work. Expected: 1,2,3,4, got: 0,0,0,0]
+    expected: FAIL
+
+  [WebGL test #9: gl.checkFramebufferStatus(gl.FRAMEBUFFER) should be 36053. Was 36054.]
+    expected: FAIL
+
+  [WebGL test #10: getError expected: NO_ERROR. Was INVALID_ENUM : clearBuffer with no srcOffset should succeed]
+    expected: FAIL
+
+  [WebGL test #16: getError expected: INVALID_VALUE. Was INVALID_FRAMEBUFFER_OPERATION : clearBuffer with srcOffset = 4 should fail: out of bounds]
+    expected: FAIL
+
+  [WebGL test #4: getError expected: NO_ERROR. Was INVALID_FRAMEBUFFER_OPERATION : clearBuffer with srcOffset = 0 should succeed]
+    expected: FAIL
+
+  [WebGL test #15: clearBuffer fails to work. Expected: 3,4,5,6, got: 0,0,0,0]
+    expected: FAIL
+
+  [WebGL test #8: getError expected: INVALID_VALUE. Was INVALID_FRAMEBUFFER_OPERATION : clearBuffer with srcOffset = 4 should fail: out of bounds]
+    expected: FAIL
+
+  [WebGL test #6: getError expected: NO_ERROR. Was INVALID_FRAMEBUFFER_OPERATION : clearBuffer with srcOffset = 2 should succeed]
+    expected: FAIL
+
+  [WebGL test #7: clearBuffer fails to work. Expected: 3,4,5,6, got: 0,0,0,0]
+    expected: FAIL
+
+  [WebGL test #12: getError expected: NO_ERROR. Was INVALID_FRAMEBUFFER_OPERATION : clearBuffer with srcOffset = 0 should succeed]
+    expected: FAIL
+
   [WebGL test #1: gl.checkFramebufferStatus(gl.FRAMEBUFFER) should be 36053. Was 36054.]
     expected: FAIL
 
-  [WebGL test #2: successfullyParsed should be true (of type boolean). Was undefined (of type undefined).]
+  [WebGL test #3: clearBuffer fails to work. Expected: 1,2,3,4, got: 0,0,0,0]
     expected: FAIL
 
diff --git a/tests/wpt/webgl/meta/conformance2/rendering/clearbufferfv-with-alpha-false.html.ini b/tests/wpt/webgl/meta/conformance2/rendering/clearbufferfv-with-alpha-false.html.ini
deleted file mode 100644
index 11034a14305..00000000000
--- a/tests/wpt/webgl/meta/conformance2/rendering/clearbufferfv-with-alpha-false.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[clearbufferfv-with-alpha-false.html]
-  expected: ERROR
-  [WebGL test #1: successfullyParsed should be true (of type boolean). Was undefined (of type undefined).]
-    expected: FAIL
-