Bug 1124430 - Implement GetFragDataLocation. - r=kamidphish

dom/canvas/WebGL2ContextPrograms.cpp

@@ -4,16 +4,25 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "WebGL2Context.h"
-#include "GLContext.h"
 
-using namespace mozilla;
-using namespace mozilla::dom;
+#include "GLContext.h"
+#include "WebGLProgram.h"
+
+namespace mozilla {
 
 // -------------------------------------------------------------------------
 // Programs and shaders
+
 GLint
-WebGL2Context::GetFragDataLocation(WebGLProgram* program, const nsAString& name)
+WebGL2Context::GetFragDataLocation(WebGLProgram* prog, const nsAString& name)
 {
-    MOZ_CRASH("Not Implemented.");
-    return 0;
+    if (IsContextLost())
+        return -1;
+
+    if (!ValidateObject("getFragDataLocation: program", prog))
+        return -1;
+
+    return prog->GetFragDataLocation(name);
 }
+
+} // namespace mozilla

dom/canvas/WebGLProgram.cpp

@@ -212,6 +212,7 @@ QueryProgramInfo(WebGLProgram* prog, gl::GLContext* gl)
 
 webgl::LinkedProgramInfo::LinkedProgramInfo(WebGLProgram* aProg)
     : prog(aProg)
+    , fragDataMap(nullptr)
 { }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -417,6 +418,29 @@ WebGLProgram::GetAttribLocation(const nsAString& userName_wide) const
     return gl->fGetAttribLocation(mGLName, mappedName.BeginReading());
 }
 
+GLint
+WebGLProgram::GetFragDataLocation(const nsAString& userName_wide) const
+{
+    if (!ValidateGLSLVariableName(userName_wide, mContext, "getFragDataLocation"))
+        return -1;
+
+    if (!IsLinked()) {
+        mContext->ErrorInvalidOperation("getFragDataLocation: `program` must be linked.");
+        return -1;
+    }
+
+    const NS_LossyConvertUTF16toASCII userName(userName_wide);
+
+    nsCString mappedName;
+    if (!LinkInfo()->FindFragData(userName, &mappedName))
+        return -1;
+
+    gl::GLContext* gl = mContext->GL();
+    gl->MakeCurrent();
+
+    return gl->fGetFragDataLocation(mGLName, mappedName.BeginReading());
+}
+
 void
 WebGLProgram::GetProgramInfoLog(nsAString* const out) const
 {

dom/canvas/WebGLProgram.h

@@ -38,6 +38,7 @@ struct LinkedProgramInfo MOZ_FINAL
     // user-facing `GLActiveInfo::name`s, without any final "[0]".
     std::map<nsCString, const WebGLActiveInfo*> attribMap;
     std::map<nsCString, const WebGLActiveInfo*> uniformMap;
+    std::map<nsCString, const nsCString>* fragDataMap;
 
     // Needed for draw call validation.
     std::set<GLuint> activeAttribLocs;
@@ -66,6 +67,17 @@ struct LinkedProgramInfo MOZ_FINAL
         return true;
     }
 
+    bool FindFragData(const nsCString& baseUserName,
+                      nsCString* const out_baseMappedName) const
+    {
+        if (!fragDataMap) {
+            *out_baseMappedName = baseUserName;
+            return true;
+        }
+
+        MOZ_CRASH("Not implemented.");
+    }
+
     bool HasActiveAttrib(GLuint loc) const {
         auto itr = activeAttribLocs.find(loc);
         return itr != activeAttribLocs.end();
@@ -100,6 +112,7 @@ public:
     already_AddRefed<WebGLActiveInfo> GetActiveUniform(GLuint index) const;
     void GetAttachedShaders(nsTArray<nsRefPtr<WebGLShader>>* const out) const;
     GLint GetAttribLocation(const nsAString& name) const;
+    GLint GetFragDataLocation(const nsAString& name) const;
     void GetProgramInfoLog(nsAString* const out) const;
     JS::Value GetProgramParameter(GLenum pname) const;
     already_AddRefed<WebGLUniformLocation> GetUniformLocation(const nsAString& name) const;