Adding GfxDriver/OpenGL/OpenGLShaderProgram class

source/GfxDriver/OpenGL/OpenGLShaderProgram.cpp

@@ -0,0 +1,186 @@
+
+#include "OpenGLShaderProgram.h"
+
+namespace sp {
+
+OpenGLShaderProgram::OpenGLShaderProgram()
+{
+	m_extension = "glsl";
+    m_id = glCreateProgram();
+}
+
+
+OpenGLShaderProgram::~OpenGLShaderProgram() 
+{
+	if (m_id > 0) {
+		glDeleteProgram(m_id);
+	}
+}
+
+bool OpenGLShaderProgram::loadFromMemory(const std::string& source, ShaderType type)
+{
+	const char *s = source.c_str();
+
+	GLuint shader_id = glCreateShader(type == ShaderType::Vertex
+        ? GL_VERTEX_SHADER : GL_FRAGMENT_SHADER);
+
+	glShaderSource(shader_id, 1, &s, NULL);
+
+	if (!compileShader(shader_id)) {
+		return false;
+	}
+
+	return attachShader(shader_id);
+}
+
+bool OpenGLShaderProgram::link()
+{
+	GLint status;
+
+	glLinkProgram(m_id);
+
+	// Query OpenGL for link status.
+	glGetProgramiv(m_id, GL_LINK_STATUS, &status);
+	m_linked = status == GL_TRUE;
+
+	if (!m_linked) {
+		m_error = fetchErrorLog();
+	}
+	return m_linked;
+}
+
+// Enable this shader
+// All shader operations after this call will affect this shader.
+void OpenGLShaderProgram::enable() const
+{
+	glUseProgram(m_id);
+}
+
+// Disable this shader
+// Operations will no longer affect this shader after this call.
+void OpenGLShaderProgram::disable() const
+{
+	glUseProgram(0);
+}
+
+// ---------------------
+// Variables.
+// ---------------------
+
+bool OpenGLShaderProgram::setMVPMatrix(const Matrix4f& matrix)
+{
+	return setUniform("u_MVP", matrix);
+}
+
+// ---------------------
+//  General Variables.
+// ---------------------
+
+bool OpenGLShaderProgram::setAttribute(const std::string& name, float value) const
+{
+	int loc;
+	if (getAttribLoc(name, loc)) {
+		glVertexAttrib1f(loc, value);
+		return true;
+	}
+	return false;
+}
+
+bool OpenGLShaderProgram::setAttribute(const std::string& name, const Matrix4f& matrix) const
+{
+	int loc;
+	if (getAttribLoc(name, loc)) {
+		glVertexAttrib4fv(loc, matrix.e);
+		return true;
+	}
+	return false;
+}
+
+bool OpenGLShaderProgram::setUniform(const std::string& name, const Matrix4f& matrix) const
+{
+	int loc;
+	if (getUniformLoc(name, loc)) {
+		glUniformMatrix4fv(loc, 1, GL_FALSE, matrix.e);
+		return true;
+	}
+	return false;
+}
+
+bool OpenGLShaderProgram::setUniform(const std::string& name, const Color& color) const
+{
+	int loc;
+	if (getUniformLoc(name, loc)) {
+		Vector4f c = color.toRGBAf();
+
+		glUniform4f(loc, c.x, c.y, c.z, c.w);
+		return true;
+	}
+	return false;
+}
+
+bool OpenGLShaderProgram::getAttribLoc(const std::string& name, int& loc) const
+{
+	loc = glGetAttribLocation(m_id, name.c_str());
+	if (loc < 0) {
+		m_error = "Attribute variable '" + name + "' was not found in shader.";
+		return false;
+	}
+	return true;
+}
+
+bool OpenGLShaderProgram::getUniformLoc(const std::string& name, int& loc) const
+{
+	loc = glGetUniformLocation(m_id, name.c_str());
+	if (loc < 0) {
+		m_error = std::string("Uniform variable '" + name + "' was not found in shader.");
+		return false;
+	}
+	return true;
+}
+
+std::string OpenGLShaderProgram::fetchErrorLog() const
+{
+	GLchar buf[4096] = { '\0' };
+
+	glGetProgramInfoLog(m_id, sizeof(buf), NULL, buf);
+
+	return std::string(buf);
+}
+
+bool OpenGLShaderProgram::compileShader(GLuint id)
+{
+	glCompileShader(id);
+		GLenum err;
+
+		// Query OpenGL for status.
+		GLint status;
+		glGetShaderiv(id, GL_COMPILE_STATUS, &status);
+		if (status == GL_FALSE) {
+			GLchar buf[4096] = { '\0' };
+			glGetShaderInfoLog(id, sizeof(buf), NULL, buf);
+			m_error = std::string(buf);
+			return false;
+		}
+		return true;
+}
+
+bool OpenGLShaderProgram::attachShader(GLuint id)
+{
+	GLenum err;
+
+	glAttachShader(m_id, id);
+	err = glGetError();
+	if (err == GL_INVALID_VALUE) {
+		m_error = "Invalid Value";
+		return false;
+	} else if (err == GL_INVALID_OPERATION) {
+		m_error = "Invalid operation";
+		return false;
+	} else if (err != GL_NO_ERROR) {
+		m_error = "Unkown Error";
+		return false;
+	} 
+	return true;
+}
+
+} // namespace sp

source/GfxDriver/OpenGL/OpenGLShaderProgram.h

@@ -0,0 +1,70 @@
+
+#ifndef SPECTRE_GFXDRIVER_OPENGL_OPENGLSHADERPROGRAM_H
+#define SPECTRE_GFXDRIVER_OPENGL_OPENGLSHADERPROGRAM_H
+
+#include <Graphics/GL/gl.h>
+#include <Spectre/GfxDriver/ShaderProgram.h>
+
+namespace sp {
+
+class OpenGLShaderProgram : public ShaderProgram
+{
+public:
+	OpenGLShaderProgram();
+	virtual ~OpenGLShaderProgram();
+
+	// Load a shader from memory.
+	virtual bool loadFromMemory(const std::string& source, ShaderType type);
+
+	// Link the program.
+	virtual bool link();
+
+	// Enable this shader
+	// All shader operations after this call will affect this shader.
+	virtual void enable() const;
+
+	// Disable this shader
+	// Operations will no longer affect this shader after this call.
+	virtual void disable() const;
+
+	// ---------------------
+	// Variables.
+	// ---------------------
+
+	virtual bool setMVPMatrix(const Matrix4f& matrix);
+
+	// ---------------------
+	//  General Variables.
+	// ---------------------
+
+	virtual bool setAttribute(const std::string& name, float value) const;
+
+	virtual bool setAttribute(const std::string& name, const Matrix4f& matrix) const;
+
+	virtual bool setUniform(const std::string& name, const Matrix4f& matrix) const;
+
+	virtual bool setUniform(const std::string& name, const Color& color) const;
+
+protected :
+
+	// Compile a shader.
+	bool compileShader(GLuint id);
+
+	// Attach shader to program.
+	bool attachShader(GLuint id);
+
+	bool getAttribLoc(const std::string& name, int& loc) const;
+
+	bool getUniformLoc(const std::string& name, int& loc) const;
+
+	std::string fetchErrorLog() const;
+
+protected :
+
+	// Program ID
+	GLuint m_id;
+};
+
+} // namespace sp
+
+#endif /* SPECTRE_GFXDRIVER_OPENGL_OPENGLSHADERPROGRAM_H */