Auto merge of #25959 - jdm:webgl_vertex_array, r=jdm

Add VertexArrayObject support for WebGL2

The implementation was already in place for OpenGL ES.
My approach with this patch is to add support for WebGL2 by
sharing the implementation between the WebGL2 and GLES.

Sadly I couldn't manage to place the WebGL2 and OpenGL ES variant to the same slot in `WebGLRenderingContext`, therefore I had to do same code duplication.

Fixes #25956.

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- [x] There are tests for these changes

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1 files changed, 100 insertions, 0 deletions

diff --git a/components/script/dom/webglvertexarrayobject.rs b/components/script/dom/webglvertexarrayobject.rs
new file mode 100644
index 00000000000..48355d05557
--- /dev/null
+++ b/components/script/dom/webglvertexarrayobject.rs
@@ -0,0 +1,100 @@
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::cell::Ref;
+use crate::dom::bindings::codegen::Bindings::WebGLVertexArrayObjectBinding;
+use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
+use crate::dom::bindings::root::{DomRoot, MutNullableDom};
+use crate::dom::vertexarrayobject::{VertexArrayObject, VertexAttribData};
+use crate::dom::webglbuffer::WebGLBuffer;
+use crate::dom::webglobject::WebGLObject;
+use crate::dom::webglrenderingcontext::WebGLRenderingContext;
+use canvas_traits::webgl::{ActiveAttribInfo, WebGLResult, WebGLVertexArrayId};
+use dom_struct::dom_struct;
+
+#[dom_struct]
+pub struct WebGLVertexArrayObject {
+    webgl_object_: WebGLObject,
+    array_object: VertexArrayObject,
+}
+
+impl WebGLVertexArrayObject {
+    fn new_inherited(context: &WebGLRenderingContext, id: Option<WebGLVertexArrayId>) -> Self {
+        Self {
+            webgl_object_: WebGLObject::new_inherited(context),
+            array_object: VertexArrayObject::new(context, id),
+        }
+    }
+
+    pub fn new(context: &WebGLRenderingContext, id: Option<WebGLVertexArrayId>) -> DomRoot<Self> {
+        reflect_dom_object(
+            Box::new(WebGLVertexArrayObject::new_inherited(context, id)),
+            &*context.global(),
+            WebGLVertexArrayObjectBinding::Wrap,
+        )
+    }
+
+    pub fn id(&self) -> Option<WebGLVertexArrayId> {
+        self.array_object.id()
+    }
+
+    pub fn is_deleted(&self) -> bool {
+        self.array_object.is_deleted()
+    }
+
+    pub fn delete(&self, fallible: bool) {
+        self.array_object.delete(fallible);
+    }
+
+    pub fn ever_bound(&self) -> bool {
+        self.array_object.ever_bound()
+    }
+
+    pub fn set_ever_bound(&self) {
+        self.array_object.set_ever_bound();
+    }
+
+    pub fn element_array_buffer(&self) -> &MutNullableDom<WebGLBuffer> {
+        self.array_object.element_array_buffer()
+    }
+
+    pub fn get_vertex_attrib(&self, index: u32) -> Option<Ref<VertexAttribData>> {
+        self.array_object.get_vertex_attrib(index)
+    }
+
+    pub fn vertex_attrib_pointer(
+        &self,
+        index: u32,
+        size: i32,
+        type_: u32,
+        normalized: bool,
+        stride: i32,
+        offset: i64,
+    ) -> WebGLResult<()> {
+        self.array_object
+            .vertex_attrib_pointer(index, size, type_, normalized, stride, offset)
+    }
+
+    pub fn vertex_attrib_divisor(&self, index: u32, value: u32) {
+        self.array_object.vertex_attrib_divisor(index, value);
+    }
+
+    pub fn enabled_vertex_attrib_array(&self, index: u32, value: bool) {
+        self.array_object.enabled_vertex_attrib_array(index, value);
+    }
+
+    pub fn unbind_buffer(&self, buffer: &WebGLBuffer) {
+        self.array_object.unbind_buffer(buffer);
+    }
+
+    pub fn validate_for_draw(
+        &self,
+        required_len: u32,
+        instance_count: u32,
+        active_attribs: &[ActiveAttribInfo],
+    ) -> WebGLResult<()> {
+        self.array_object
+            .validate_for_draw(required_len, instance_count, active_attribs)
+    }
+}