OPENGL: Do not hardcode any uniform/attribute handling in Shader.

5 files changed, 35 insertions, 27 deletions

diff --git a/backends/graphics/opengl/opengl-func.h b/backends/graphics/opengl/opengl-func.h
index ad7c572ca9..4e44c13d0f 100644
--- a/backends/graphics/opengl/opengl-func.h
+++ b/backends/graphics/opengl/opengl-func.h
@@ -107,6 +107,7 @@ GL_FUNC_DEF(GLenum, glGetError, ());
 
 #if !USE_FORCED_GLES
 GL_FUNC_2_DEF(void, glEnableVertexAttribArray, glEnableVertexAttribArrayARB, (GLuint index));
+GL_FUNC_2_DEF(void, glDisableVertexAttribArray, glDisableVertexAttribArrayARB, (GLuint index));
 GL_FUNC_2_DEF(void, glUniform1i, glUniform1iARB, (GLint location, GLint v0));
 GL_FUNC_2_DEF(void, glUniform1f, glUniform1fARB, (GLint location, GLfloat v0));
 GL_FUNC_2_DEF(void, glUniformMatrix4fv, glUniformMatrix4fvARB, (GLint location, GLsizei count, GLboolean transpose, const GLfloat *value));
@@ -122,6 +123,7 @@ GL_FUNC_2_DEF(void, glUseProgram, glUseProgramObjectARB, (GLprogram program));
 GL_FUNC_2_DEF(void, glGetProgramiv, glGetObjectParameterivARB, (GLprogram program, GLenum pname, GLint *params));
 GL_FUNC_2_DEF(void, glGetProgramInfoLog, glGetInfoLogARB, (GLprogram program, GLsizei bufSize, GLsizei *length, GLchar *infoLog));
 GL_FUNC_2_DEF(void, glBindAttribLocation, glBindAttribLocationARB, (GLprogram program, GLuint index, const GLchar *name));
+GL_FUNC_2_DEF(GLint, glGetAttribLocation, glGetAttribLocationARB, (GLprogram program, const GLchar *name));
 GL_FUNC_2_DEF(GLint, glGetUniformLocation, glGetUniformLocationARB, (GLprogram program, const GLchar *name));
 
 GL_FUNC_2_DEF(GLshader, glCreateShader, glCreateShaderObjectARB, (GLenum type));
diff --git a/backends/graphics/opengl/pipelines/shader.cpp b/backends/graphics/opengl/pipelines/shader.cpp
index 46e81423c5..c7befe22b8 100644
--- a/backends/graphics/opengl/pipelines/shader.cpp
+++ b/backends/graphics/opengl/pipelines/shader.cpp
@@ -29,11 +29,14 @@ namespace OpenGL {
 #if !USE_FORCED_GLES
 ShaderPipeline::ShaderPipeline(Shader *shader)
     : _activeShader(shader) {
+	_vertexAttribLocation = shader->getAttributeLocation("position");
+	_texCoordAttribLocation = shader->getAttributeLocation("texCoordIn");
+	_colorAttribLocation = shader->getAttributeLocation("blendColorIn");
 }
 
 void ShaderPipeline::activateInternal() {
-	GL_CALL(glEnableVertexAttribArray(kPositionAttribLocation));
-	GL_CALL(glEnableVertexAttribArray(kTexCoordAttribLocation));
+	GL_CALL(glEnableVertexAttribArray(_vertexAttribLocation));
+	GL_CALL(glEnableVertexAttribArray(_texCoordAttribLocation));
 
 	if (g_context.multitextureSupported) {
 		GL_CALL(glActiveTexture(GL_TEXTURE0));
@@ -43,18 +46,21 @@ void ShaderPipeline::activateInternal() {
 }
 
 void ShaderPipeline::deactivateInternal() {
+	GL_CALL(glDisableVertexAttribArray(_vertexAttribLocation));
+	GL_CALL(glDisableVertexAttribArray(_texCoordAttribLocation));
+
 	_activeShader->deactivate();
 }
 
 void ShaderPipeline::setColor(GLfloat r, GLfloat g, GLfloat b, GLfloat a) {
-	GL_CALL(glVertexAttrib4f(kColorAttribLocation, r, g, b, a));
+	GL_CALL(glVertexAttrib4f(_colorAttribLocation, r, g, b, a));
 }
 
 void ShaderPipeline::drawTexture(const GLTexture &texture, const GLfloat *coordinates) {
 	texture.bind();
 
-	GL_CALL(glVertexAttribPointer(kTexCoordAttribLocation, 2, GL_FLOAT, GL_FALSE, 0, texture.getTexCoords()));
-	GL_CALL(glVertexAttribPointer(kPositionAttribLocation, 2, GL_FLOAT, GL_FALSE, 0, coordinates));
+	GL_CALL(glVertexAttribPointer(_texCoordAttribLocation, 2, GL_FLOAT, GL_FALSE, 0, texture.getTexCoords()));
+	GL_CALL(glVertexAttribPointer(_vertexAttribLocation, 2, GL_FLOAT, GL_FALSE, 0, coordinates));
 	GL_CALL(glDrawArrays(GL_TRIANGLE_STRIP, 0, 4));
 }
 
diff --git a/backends/graphics/opengl/pipelines/shader.h b/backends/graphics/opengl/pipelines/shader.h
index 8e82bd7a31..95167ee03f 100644
--- a/backends/graphics/opengl/pipelines/shader.h
+++ b/backends/graphics/opengl/pipelines/shader.h
@@ -44,6 +44,10 @@ protected:
 	virtual void activateInternal();
 	virtual void deactivateInternal();
 
+	GLint _vertexAttribLocation;
+	GLint _texCoordAttribLocation;
+	GLint _colorAttribLocation;
+
 	Shader *const _activeShader;
 };
 #endif // !USE_FORCED_GLES
diff --git a/backends/graphics/opengl/shader.cpp b/backends/graphics/opengl/shader.cpp
index 59749ba1f0..652da57dfa 100644
--- a/backends/graphics/opengl/shader.cpp
+++ b/backends/graphics/opengl/shader.cpp
@@ -159,10 +159,6 @@ bool Shader::recreate() {
 	GL_CALL(glAttachShader(_program, vertexShader));
 	GL_CALL(glAttachShader(_program, fragmentShader));
 
-	GL_CALL(glBindAttribLocation(_program, kPositionAttribLocation, "position"));
-	GL_CALL(glBindAttribLocation(_program, kTexCoordAttribLocation, "texCoordIn"));
-	GL_CALL(glBindAttribLocation(_program, kColorAttribLocation,    "blendColorIn"));
-
 	GL_CALL(glLinkProgram(_program));
 
 	GL_CALL(glDetachShader(_program, fragmentShader));
@@ -199,18 +195,6 @@ bool Shader::recreate() {
 		}
 	}
 
-	if (getUniformLocation("projection") == -1) {
-		warning("Shader misses \"projection\" uniform.");
-		destroy();
-		return false;
-	}
-
-	if (!setUniform1I("texture", 0)) {
-		warning("Shader misses \"texture\" uniform.");
-		destroy();
-		return false;
-	}
-
 	return true;
 }
 
@@ -230,6 +214,12 @@ void Shader::deactivate() {
 	_isActive = false;
 }
 
+GLint Shader::getAttributeLocation(const char *name) const {
+	GLint result = -1;
+	GL_ASSIGN(result, glGetAttribLocation(_program, name));
+	return result;
+}
+
 GLint Shader::getUniformLocation(const char *name) const {
 	GLint result = -1;
 	GL_ASSIGN(result, glGetUniformLocation(_program, name));
@@ -310,6 +300,10 @@ void ShaderManager::notifyCreate() {
 		_builtIn[kDefault] = new Shader(g_defaultVertexShader, g_defaultFragmentShader);
 		_builtIn[kCLUT8LookUp] = new Shader(g_defaultVertexShader, g_lookUpFragmentShader);
 		_builtIn[kCLUT8LookUp]->setUniform1I("palette", 1);
+
+		for (uint i = 0; i < kMaxUsages; ++i) {
+			_builtIn[i]->setUniform1I("texture", 0);
+		}
 	} else {
 		for (int i = 0; i < ARRAYSIZE(_builtIn); ++i) {
 			_builtIn[i]->recreate();
diff --git a/backends/graphics/opengl/shader.h b/backends/graphics/opengl/shader.h
index 1aee8ed681..f219861244 100644
--- a/backends/graphics/opengl/shader.h
+++ b/backends/graphics/opengl/shader.h
@@ -33,12 +33,6 @@
 
 namespace OpenGL {
 
-enum {
-	kPositionAttribLocation = 0,
-	kTexCoordAttribLocation = 1,
-	kColorAttribLocation    = 2
-};
-
 /**
  * A generic uniform value interface for a shader program.
  */
@@ -127,6 +121,14 @@ public:
 	void deactivate();
 
 	/**
+	 * Return location for attribute with given name.
+	 *
+	 * @param name Name of the attribute to look up in the shader.
+	 * @return The loctaion of -1 if attribute was not found.
+	 */
+	GLint getAttributeLocation(const char *name) const;
+
+	/**
 	 * Return location for uniform with given name.
 	 *
 	 * @param name Name of the uniform to look up in the shader.