In fact, lets just replace Shader:getUniformVariable with Shader:hasUniform. The latter returns true if the uniform with the specified name exists and contributes to the final output of the shader.

--HG--
branch : minor

src/modules/graphics/opengl/Shader.cpp

@@ -621,21 +621,9 @@ int Shader::getTextureUnit(const std::string &name)
 	return texunit;
 }
 
-Shader::UniformType Shader::getUniformVariable(const std::string &name, int &components, int &count)
+bool Shader::hasUniform(const std::string &name) const
 {
-	auto it = uniforms.find(name);
-
-	if (it == uniforms.end())
-	{
-		components = 0;
-		count = 0;
-		return UNIFORM_UNKNOWN;
-	}
-
-	components = getUniformTypeSize(it->second.type);
-	count = (int) it->second.count;
-
-	return it->second.baseType;
+	return uniforms.find(name) != uniforms.end();
 }
 
 GLint Shader::getAttribLocation(const std::string &name)

src/modules/graphics/opengl/Shader.h

@@ -168,17 +168,10 @@ public:
 	void sendTexture(const std::string &name, Texture *texture);
 
 	/**
-	 * Gets the type, number of components, and number of array elements of
-	 * an active uniform variable in the shader. If a uniform variable with the
-	 * specified name doesn't exist, returns UNIFORM_UNKNOWN and sets the
-	 * 'components' and 'count' values to 0.
-	 *
-	 * @param name The name of the uniform variable in the source code.
-	 * @param[out] components Number of components of the variable (2 for vec2.)
-	 * @param[out] count Number of array elements, if the variable is an array.
-	 * @return The base type of the uniform variable.
+	 * Gets whether a uniform with the specified name exists and is actively
+	 * used in the shader.
 	 **/
-	UniformType getUniformVariable(const std::string &name, int &components, int &count);
+	bool hasUniform(const std::string &name) const;
 
 	GLint getAttribLocation(const std::string &name);
 

src/modules/graphics/opengl/wrap_Shader.cpp

@@ -324,36 +324,12 @@ int w_Shader_send(lua_State *L)
 	return luaL_argerror(L, 3, "number, boolean, table, image, or canvas expected");
 }
 
-int w_Shader_getUniformVariable(lua_State *L)
+int w_Shader_hasUniform(lua_State *L)
 {
 	Shader *shader = luax_checkshader(L, 1);
 	const char *name = luaL_checkstring(L, 2);
-
-	int components = 0;
-	int arrayelements = 0;
-	Shader::UniformType type = Shader::UNIFORM_UNKNOWN;
-
-	type = shader->getUniformVariable(name, components, arrayelements);
-
-	// Check if the variable exists (function will set components to 0 if not.)
-	if (components > 0)
-	{
-		const char *tname = nullptr;
-		if (!Shader::getConstant(type, tname))
-			return luaL_error(L, "Unknown uniform variable type name.");
-
-		lua_pushstring(L, tname);
-		lua_pushinteger(L, components);
-		lua_pushinteger(L, arrayelements);
-	}
-	else
-	{
-		lua_pushnil(L);
-		lua_pushnil(L);
-		lua_pushnil(L);
-	}
-
-	return 3;
+	luax_pushboolean(L, shader->hasUniform(name));
+	return 1;
 }
 
 static const luaL_Reg w_Shader_functions[] =
@@ -366,7 +342,7 @@ static const luaL_Reg w_Shader_functions[] =
 	{ "sendMatrix",  w_Shader_sendMatrix },
 	{ "sendTexture", w_Shader_sendTexture },
 	{ "send",        w_Shader_send },
-	{ "getUniformVariable", w_Shader_getUniformVariable },
+	{ "hasUniform",  w_Shader_hasUniform },
 	{ 0, 0 }
 };