Auto merge of #20144 - mkollaro:gettexparameter, r=jdm

Add WebGL function glGetTexParameter

<!-- Please describe your changes on the following line: -->
Add WebGL function glGetTexParameter

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix part of #10209

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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3 files changed, 38 insertions, 1 deletions

diff --git a/components/script/dom/webgl2renderingcontext.rs b/components/script/dom/webgl2renderingcontext.rs
index 9bf016f9631..2a25c450b08 100644
--- a/components/script/dom/webgl2renderingcontext.rs
+++ b/components/script/dom/webgl2renderingcontext.rs
@@ -115,6 +115,12 @@ impl WebGL2RenderingContextMethods for WebGL2RenderingContext {
         self.base.GetParameter(cx, parameter)
     }
 
+    #[allow(unsafe_code)]
+    /// https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.8
+    unsafe fn GetTexParameter(&self, cx: *mut JSContext, target: u32, pname: u32) -> JSVal {
+        self.base.GetTexParameter(cx, target, pname)
+    }
+
     /// https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.3
     fn GetError(&self) -> u32 {
         self.base.GetError()
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 61f05a923e8..fa1015582cf 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -1336,6 +1336,37 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
         }
     }
 
+    #[allow(unsafe_code)]
+    // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.8
+    unsafe fn GetTexParameter(&self, _cx: *mut JSContext, target: u32, pname: u32) -> JSVal {
+        let texture = match target {
+            constants::TEXTURE_2D |
+            constants::TEXTURE_CUBE_MAP => self.bound_texture(target),
+            _ => {
+                self.webgl_error(InvalidEnum);
+                return NullValue();
+            }
+        };
+        if texture.is_some() {
+            let (sender, receiver) = webgl_channel().unwrap();
+            self.send_command(WebGLCommand::GetTexParameter(target, pname, sender));
+            match handle_potential_webgl_error!(self, receiver.recv().unwrap(), WebGLParameter::Invalid) {
+                WebGLParameter::Int(val) => Int32Value(val),
+                WebGLParameter::Bool(_) => panic!("Texture parameter should not be bool"),
+                WebGLParameter::Float(_) => panic!("Texture parameter should not be float"),
+                WebGLParameter::FloatArray(_) => panic!("Texture parameter should not be float array"),
+                WebGLParameter::String(_) => panic!("Texture parameter should not be string"),
+                WebGLParameter::Invalid => {
+                    self.webgl_error(InvalidEnum);
+                    NullValue()
+                }
+            }
+        } else {
+            self.webgl_error(InvalidOperation);
+            NullValue()
+        }
+    }
+
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.3
     fn GetError(&self) -> u32 {
         let error_code = if let Some(error) = self.last_error.get() {
diff --git a/components/script/dom/webidls/WebGLRenderingContext.webidl b/components/script/dom/webidls/WebGLRenderingContext.webidl
index ec729d1b5fb..3f845126701 100644
--- a/components/script/dom/webidls/WebGLRenderingContext.webidl
+++ b/components/script/dom/webidls/WebGLRenderingContext.webidl
@@ -600,7 +600,7 @@ interface WebGLRenderingContextBase
 
     DOMString? getShaderSource(WebGLShader? shader);
 
-    //any getTexParameter(GLenum target, GLenum pname);
+    any getTexParameter(GLenum target, GLenum pname);
 
     //any getUniform(WebGLProgram? program, WebGLUniformLocation? location);