gl_shader_util: separate shader object creation and program object creation

This commit is contained in:
wwylele 2018-04-10 00:24:37 +03:00
parent 8b858f1bf7
commit d2ee40dc45
2 changed files with 64 additions and 57 deletions

View File

@ -10,66 +10,67 @@
namespace GLShader { namespace GLShader {
GLuint LoadProgram(const char* vertex_shader, const char* fragment_shader) { GLuint LoadShader(const char* source, GLenum type) {
const char* debug_type;
switch (type) {
case GL_VERTEX_SHADER:
debug_type = "vertex";
break;
case GL_GEOMETRY_SHADER:
debug_type = "geometry";
break;
case GL_FRAGMENT_SHADER:
debug_type = "fragment";
break;
default:
UNREACHABLE();
}
// Create the shaders GLuint shader_id = glCreateShader(type);
GLuint vertex_shader_id = glCreateShader(GL_VERTEX_SHADER); glShaderSource(shader_id, 1, &source, nullptr);
GLuint fragment_shader_id = glCreateShader(GL_FRAGMENT_SHADER); NGLOG_DEBUG(Render_OpenGL, "Compiling {} shader...", debug_type);
glCompileShader(shader_id);
GLint result = GL_FALSE; GLint result = GL_FALSE;
int info_log_length; GLint info_log_length;
glGetShaderiv(shader_id, GL_COMPILE_STATUS, &result);
// Compile Vertex Shader glGetShaderiv(shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
LOG_DEBUG(Render_OpenGL, "Compiling vertex shader...");
glShaderSource(vertex_shader_id, 1, &vertex_shader, nullptr);
glCompileShader(vertex_shader_id);
// Check Vertex Shader
glGetShaderiv(vertex_shader_id, GL_COMPILE_STATUS, &result);
glGetShaderiv(vertex_shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
if (info_log_length > 1) { if (info_log_length > 1) {
std::vector<char> vertex_shader_error(info_log_length); std::vector<char> shader_error(info_log_length);
glGetShaderInfoLog(vertex_shader_id, info_log_length, nullptr, &vertex_shader_error[0]); glGetShaderInfoLog(shader_id, info_log_length, nullptr, &shader_error[0]);
if (result == GL_TRUE) { if (result == GL_TRUE) {
LOG_DEBUG(Render_OpenGL, "%s", &vertex_shader_error[0]); NGLOG_DEBUG(Render_OpenGL, "{}", &shader_error[0]);
} else { } else {
LOG_ERROR(Render_OpenGL, "Error compiling vertex shader:\n%s", &vertex_shader_error[0]); NGLOG_ERROR(Render_OpenGL, "Error compiling {} shader:\n{}", debug_type,
&shader_error[0]);
NGLOG_ERROR(Render_OpenGL, "Shader source code:\n{}", source);
} }
} }
return shader_id;
// Compile Fragment Shader
LOG_DEBUG(Render_OpenGL, "Compiling fragment shader...");
glShaderSource(fragment_shader_id, 1, &fragment_shader, nullptr);
glCompileShader(fragment_shader_id);
// Check Fragment Shader
glGetShaderiv(fragment_shader_id, GL_COMPILE_STATUS, &result);
glGetShaderiv(fragment_shader_id, GL_INFO_LOG_LENGTH, &info_log_length);
if (info_log_length > 1) {
std::vector<char> fragment_shader_error(info_log_length);
glGetShaderInfoLog(fragment_shader_id, info_log_length, nullptr, &fragment_shader_error[0]);
if (result == GL_TRUE) {
LOG_DEBUG(Render_OpenGL, "%s", &fragment_shader_error[0]);
} else {
LOG_ERROR(Render_OpenGL, "Error compiling fragment shader:\n%s",
&fragment_shader_error[0]);
}
} }
GLuint LoadProgram(bool separable_program, const std::vector<GLuint>& shaders) {
// Link the program // Link the program
LOG_DEBUG(Render_OpenGL, "Linking program..."); NGLOG_DEBUG(Render_OpenGL, "Linking program...");
GLuint program_id = glCreateProgram(); GLuint program_id = glCreateProgram();
glAttachShader(program_id, vertex_shader_id);
glAttachShader(program_id, fragment_shader_id); for (GLuint shader : shaders) {
if (shader != 0) {
glAttachShader(program_id, shader);
}
}
if (separable_program) {
glProgramParameteri(program_id, GL_PROGRAM_SEPARABLE, GL_TRUE);
}
glLinkProgram(program_id); glLinkProgram(program_id);
// Check the program // Check the program
GLint result = GL_FALSE;
GLint info_log_length;
glGetProgramiv(program_id, GL_LINK_STATUS, &result); glGetProgramiv(program_id, GL_LINK_STATUS, &result);
glGetProgramiv(program_id, GL_INFO_LOG_LENGTH, &info_log_length); glGetProgramiv(program_id, GL_INFO_LOG_LENGTH, &info_log_length);
@ -77,21 +78,19 @@ GLuint LoadProgram(const char* vertex_shader, const char* fragment_shader) {
std::vector<char> program_error(info_log_length); std::vector<char> program_error(info_log_length);
glGetProgramInfoLog(program_id, info_log_length, nullptr, &program_error[0]); glGetProgramInfoLog(program_id, info_log_length, nullptr, &program_error[0]);
if (result == GL_TRUE) { if (result == GL_TRUE) {
LOG_DEBUG(Render_OpenGL, "%s", &program_error[0]); NGLOG_DEBUG(Render_OpenGL, "{}", &program_error[0]);
} else { } else {
LOG_ERROR(Render_OpenGL, "Error linking shader:\n%s", &program_error[0]); NGLOG_ERROR(Render_OpenGL, "Error linking shader:\n{}", &program_error[0]);
} }
} }
// If the program linking failed at least one of the shaders was probably bad
if (result == GL_FALSE) {
LOG_ERROR(Render_OpenGL, "Vertex shader:\n%s", vertex_shader);
LOG_ERROR(Render_OpenGL, "Fragment shader:\n%s", fragment_shader);
}
ASSERT_MSG(result == GL_TRUE, "Shader not linked"); ASSERT_MSG(result == GL_TRUE, "Shader not linked");
glDeleteShader(vertex_shader_id); for (GLuint shader : shaders) {
glDeleteShader(fragment_shader_id); if (shader != 0) {
glDetachShader(program_id, shader);
}
}
return program_id; return program_id;
} }

View File

@ -4,16 +4,24 @@
#pragma once #pragma once
#include <vector>
#include <glad/glad.h> #include <glad/glad.h>
namespace GLShader { namespace GLShader {
/** /**
* Utility function to create and compile an OpenGL GLSL shader program (vertex + fragment shader) * Utility function to create and compile an OpenGL GLSL shader
* @param vertex_shader String of the GLSL vertex shader program * @param source String of the GLSL shader program
* @param fragment_shader String of the GLSL fragment shader program * @param type Type of the shader (GL_VERTEX_SHADER, GL_GEOMETRY_SHADER or GL_FRAGMENT_SHADER)
* @returns Handle of the newly created OpenGL shader object
*/ */
GLuint LoadProgram(const char* vertex_shader, const char* fragment_shader); GLuint LoadShader(const char* source, GLenum type);
/**
* Utility function to create and link an OpenGL GLSL shader program
* @param separable_program whether to create a separable program
* @param shaders ID of shaders to attach to the program
* @returns Handle of the newly created OpenGL program object
*/
GLuint LoadProgram(bool separable_program, const std::vector<GLuint>& shaders);
} // namespace GLShader } // namespace GLShader