Adapted Escape the Dawn engine.

src/ShaderProgram.cpp

@@ -0,0 +1,145 @@
+#include "PrecompiledHeader.h"
+#include "ShaderProgram.h"
+
+GLuint Shader::CompileShader(GLenum shaderType, std::string fileName)
+{
+	LOG_INFO("Compiling shader \"%s\"", fileName.c_str());
+
+	std::string shaderFile;
+	std::ifstream in(fileName, std::ios::in);
+	if (!in)	{
+		LOG_ERROR("Error: Failed to open shader file \"%s\"", fileName.c_str());
+		return 0;
+	}
+	in.seekg(0, std::ios::end);
+	shaderFile.resize((int)in.tellg());
+	in.seekg(0, std::ios::beg);
+	in.read(&shaderFile[0], shaderFile.size());
+	in.close();
+
+	GLuint shader = glCreateShader(shaderType);
+	if(GLERROR("glCreateShader"))
+		return 0;
+
+	const GLchar* shaderFiles = shaderFile.c_str();
+	const GLint length = shaderFile.length();
+	glShaderSource(shader, 1, &shaderFiles, &length);
+	if(GLERROR("glShaderSource"))
+		return 0;
+
+	glCompileShader(shader);
+
+	GLint compileStatus;
+	glGetShaderiv(shader, GL_COMPILE_STATUS, &compileStatus);
+	if(compileStatus != GL_TRUE) {
+		LOG_ERROR("Shader compilation failed");
+		GLsizei infoLogLength;
+		glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLength);
+		GLchar* infolog = new GLchar[infoLogLength];
+		glGetShaderInfoLog(shader, infoLogLength, &infoLogLength, infolog);
+		LOG_ERROR(infolog);
+		delete[] infolog;
+	}
+
+	if(GLERROR("glCompileShader"))
+		return 0;
+
+	return shader;
+}
+
+Shader::Shader(GLenum shaderType, std::string fileName) : m_ShaderType(shaderType), m_FileName(fileName)
+{
+	m_ShaderHandle = 0;
+}
+
+Shader::~Shader()
+{
+	if (m_ShaderHandle != 0) {
+		glDeleteShader(m_ShaderHandle);
+	}
+}
+
+GLuint Shader::Compile()
+{
+	m_ShaderHandle = CompileShader(m_ShaderType, m_FileName);
+	return m_ShaderHandle;
+}
+
+GLenum Shader::GetType() const
+{
+	return m_ShaderType;
+}
+
+std::string Shader::GetFileName() const
+{
+	return m_FileName;
+}
+
+GLuint Shader::GetHandle() const
+{
+	return m_ShaderHandle;
+}
+
+bool Shader::IsCompiled() const
+{
+	return m_ShaderHandle != 0;
+}
+
+ShaderProgram::~ShaderProgram()
+{
+	if (m_ShaderProgramHandle != 0) {
+		glDeleteProgram(m_ShaderProgramHandle);
+	}
+}
+
+void ShaderProgram::AddShader(std::shared_ptr<Shader> shader)
+{
+	m_Shaders.push_back(shader);
+}
+
+void ShaderProgram::Compile()
+{
+	for (auto &shader : m_Shaders) {
+		if (!shader->IsCompiled()) {
+			shader->Compile();
+		}
+	}
+}
+
+GLuint ShaderProgram::Link()
+{
+	if (m_Shaders.size() == 0) {
+		LOG_ERROR("Failed to link shader program: No shaders bound");
+		return 0;
+	}
+
+	LOG_INFO("Linking shader program");
+	m_ShaderProgramHandle = glCreateProgram();
+	for (auto &shader : m_Shaders) {
+		glAttachShader(m_ShaderProgramHandle, shader->GetHandle());
+	}
+	glLinkProgram(m_ShaderProgramHandle);
+	if (GLERROR("glLinkProgram"))
+		return 0;
+	m_Shaders.clear();
+
+	return m_ShaderProgramHandle;
+}
+
+GLuint ShaderProgram::GetHandle()
+{
+	return m_ShaderProgramHandle;
+}
+
+void ShaderProgram::Bind()
+{
+	if (m_ShaderProgramHandle == 0)
+		return;
+
+	glUseProgram(m_ShaderProgramHandle);
+}
+
+void ShaderProgram::Unbind()
+{
+	glActiveShaderProgram(0, 0);
+}