Auto merge of #20915 - servo:webgl, r=jdm

Implement EXT_shader_texture_lod

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3 files changed, 60 insertions, 0 deletions

diff --git a/components/script/dom/webgl_extensions/ext/extshadertexturelod.rs b/components/script/dom/webgl_extensions/ext/extshadertexturelod.rs
new file mode 100644
index 00000000000..cb574b0fb50
--- /dev/null
+++ b/components/script/dom/webgl_extensions/ext/extshadertexturelod.rs
@@ -0,0 +1,48 @@
+/* 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/. */
+
+use canvas_traits::webgl::WebGLVersion;
+use dom::bindings::codegen::Bindings::EXTShaderTextureLodBinding;
+use dom::bindings::reflector::{DomObject, Reflector, reflect_dom_object};
+use dom::bindings::root::DomRoot;
+use dom::webglrenderingcontext::WebGLRenderingContext;
+use dom_struct::dom_struct;
+use super::{WebGLExtension, WebGLExtensions, WebGLExtensionSpec};
+
+#[dom_struct]
+pub struct EXTShaderTextureLod {
+    reflector_: Reflector,
+}
+
+impl EXTShaderTextureLod {
+    fn new_inherited() -> Self {
+        Self { reflector_: Reflector::new() }
+    }
+}
+
+impl WebGLExtension for EXTShaderTextureLod {
+    type Extension = Self;
+
+    fn new(ctx: &WebGLRenderingContext) -> DomRoot<Self> {
+        reflect_dom_object(
+            Box::new(Self::new_inherited()),
+            &*ctx.global(),
+            EXTShaderTextureLodBinding::Wrap,
+        )
+    }
+
+    fn spec() -> WebGLExtensionSpec {
+        WebGLExtensionSpec::Specific(WebGLVersion::WebGL1)
+    }
+
+    fn is_supported(ext: &WebGLExtensions) -> bool {
+        ext.supports_gl_extension("GL_EXT_shader_texture_lod")
+    }
+
+    fn enable(_ext: &WebGLExtensions) {}
+
+    fn name() -> &'static str {
+        "EXT_shader_texture_lod"
+    }
+}
diff --git a/components/script/dom/webgl_extensions/ext/mod.rs b/components/script/dom/webgl_extensions/ext/mod.rs
index e64ffb9aa40..b4b58fd10e1 100644
--- a/components/script/dom/webgl_extensions/ext/mod.rs
+++ b/components/script/dom/webgl_extensions/ext/mod.rs
@@ -5,6 +5,7 @@
 use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextConstants as constants;
 use super::{ext_constants, WebGLExtension, WebGLExtensions, WebGLExtensionSpec};
 
+pub mod extshadertexturelod;
 pub mod oeselementindexuint;
 pub mod oesstandardderivatives;
 pub mod oestexturefloat;
diff --git a/components/script/dom/webidls/EXTShaderTextureLod.webidl b/components/script/dom/webidls/EXTShaderTextureLod.webidl
new file mode 100644
index 00000000000..08396c477a9
--- /dev/null
+++ b/components/script/dom/webidls/EXTShaderTextureLod.webidl
@@ -0,0 +1,11 @@
+/* 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/. */
+/*
+ * WebGL IDL definitions scraped from the Khronos specification:
+ * https://www.khronos.org/registry/webgl/extensions/EXT_shader_texture_lod/
+ */
+
+[NoInterfaceObject]
+interface EXTShaderTextureLod {
+};