Auto merge of #10215 - ConnorGBrewster:webgl_finish, r=emilio

WebGL: Finish, Flush, DetachShader, GenerateMipmap

Implements #10212 and #10213

r? @emilio

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1 files changed, 30 insertions, 1 deletions

diff --git a/components/script/dom/webglprogram.rs b/components/script/dom/webglprogram.rs
index 338a1e8d46b..378039b03eb 100644
--- a/components/script/dom/webglprogram.rs
+++ b/components/script/dom/webglprogram.rs
@@ -94,7 +94,10 @@ impl WebGLProgram {
         let shader_slot = match shader.gl_type() {
             constants::FRAGMENT_SHADER => &self.fragment_shader,
             constants::VERTEX_SHADER => &self.vertex_shader,
-            _ => return Err(WebGLError::InvalidOperation),
+            _ => {
+                error!("detachShader: Unexpected shader type");
+                return Err(WebGLError::InvalidValue);
+            }
         };
 
         // TODO(emilio): Differentiate between same shader already assigned and other previous
@@ -110,6 +113,32 @@ impl WebGLProgram {
         Ok(())
     }
 
+    /// glDetachShader
+    pub fn detach_shader(&self, shader: &WebGLShader) -> WebGLResult<()> {
+        let shader_slot = match shader.gl_type() {
+            constants::FRAGMENT_SHADER => &self.fragment_shader,
+            constants::VERTEX_SHADER => &self.vertex_shader,
+            _ => {
+                error!("detachShader: Unexpected shader type");
+                return Err(WebGLError::InvalidValue);
+            }
+        };
+
+        match shader_slot.get() {
+            Some(ref attached_shader) if attached_shader.id() != shader.id() =>
+                return Err(WebGLError::InvalidOperation),
+            None =>
+                return Err(WebGLError::InvalidOperation),
+            _ => {}
+        }
+
+        shader_slot.set(None);
+
+        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::DetachShader(self.id, shader.id()))).unwrap();
+
+        Ok(())
+    }
+
     /// glBindAttribLocation
     pub fn bind_attrib_location(&self, index: u32, name: DOMString) -> WebGLResult<()> {
         if name.len() > MAX_UNIFORM_AND_ATTRIBUTE_LEN {