Shader::Shader(const std::string &vertex_shader_code, const std::string &fragment_shader_code) {
// Create shaders
auto vertex_shader_id = glCreateShader(GL_VERTEX_SHADER);
auto fragment_shader_id = glCreateShader(GL_FRAGMENT_SHADER);
auto result = GL_FALSE;
auto info_length = 0;
// Compile vertex shader
auto vertex_shader_code_ptr = vertex_shader_code.c_str();
glShaderSource(vertex_shader_id, 1, &vertex_shader_code_ptr, NULL);
glCompileShader(vertex_shader_id);
// Check vertex shader log
glGetShaderiv(vertex_shader_id, GL_COMPILE_STATUS, &result);
if (result == GL_FALSE) {
glGetShaderiv(vertex_shader_id, GL_INFO_LOG_LENGTH, &info_length);
std::string vertex_shader_log((unsigned int) info_length, ' ');
glGetShaderInfoLog(vertex_shader_id, info_length, NULL,
&vertex_shader_log[0]);
std::cout << "Error Compiling Vertex Shader ..." << std::endl;
std::cout << vertex_shader_log << std::endl;
}
// Compile fragment shader
auto fragment_shader_code_ptr = fragment_shader_code.c_str();
glShaderSource(fragment_shader_id, 1, &fragment_shader_code_ptr, NULL);
glCompileShader(fragment_shader_id);
// Check fragment shader log
glGetShaderiv(fragment_shader_id, GL_COMPILE_STATUS, &result);
if (result == GL_FALSE) {
glGetShaderiv(fragment_shader_id, GL_INFO_LOG_LENGTH, &info_length);
std::string fragment_shader_log((unsigned long) info_length, ' ');
glGetShaderInfoLog(fragment_shader_id, info_length, NULL,
&fragment_shader_log[0]);
std::cout << "Error Compiling Fragment Shader ..." << std::endl;
std::cout << fragment_shader_log << std::endl;
}
// Create and link the program
auto program_id = glCreateProgram();
glAttachShader(program_id, vertex_shader_id);
glAttachShader(program_id, fragment_shader_id);
glBindFragDataLocation(program_id, 0, "FragmentColor");
glLinkProgram(program_id);
// Check program log
glGetProgramiv(program_id, GL_LINK_STATUS, &result);
if (result == GL_FALSE) {
glGetProgramiv(program_id, GL_INFO_LOG_LENGTH, &info_length);
std::string program_log((unsigned long) info_length, ' ');
glGetProgramInfoLog(program_id, info_length, NULL, &program_log[0]);
std::cout << "Error Linking Shader Program ..." << std::endl;
std::cout << program_log << std::endl;
}
glDeleteShader(vertex_shader_id);
glDeleteShader(fragment_shader_id);
program = program_id;
}
std::string Program::getInfoLog() const {
int length = 0;
int written_length = 0;
getProgram(Program::InfoLogLength, &length);
if(length <= 0) {
return std::string();
}
std::vector<char> program_log(length);
glGetProgramInfoLog(program_id_, program_log.size(), &length, &program_log[0]);
return std::string(&program_log[0], length);
}
// creaza un program de tip shader
unsigned int _createProgram(const std::vector<unsigned int> &shader_objects){
int info_log_length=0,link_result=0;
//build OpenGL program object and link all the OpenGL shader objects
unsigned int gl_program_object = glCreateProgram();
for(std::vector<unsigned int>::const_iterator it=shader_objects.begin(); it!=shader_objects.end(); it++) glAttachShader(gl_program_object,(*it));
glLinkProgram(gl_program_object);
glGetProgramiv(gl_program_object, GL_LINK_STATUS, &link_result);
//if we get link errors log them
if(link_result == GL_FALSE){
glGetProgramiv(gl_program_object, GL_INFO_LOG_LENGTH, &info_log_length);
std::vector<char> program_log(info_log_length);
glGetProgramInfoLog(gl_program_object, info_log_length, NULL, &program_log[0]);
std::cout<<"Shader Loader : EROARE DE LINKARE"<<std::endl<<&program_log[0]<<std::endl;
return 0;
}
//delete the shader objects because we do not need them any more (this should be re-written if usage of separate shader objects is intended!)
for(std::vector<unsigned int>::const_iterator it=shader_objects.begin(); it!=shader_objects.end(); it++) glDeleteShader((*it));
return gl_program_object;
}
static int GenerateShaders(std::vector<AutoGLProgram> *blend_programs) {
// Limits: GL_MAX_VARYING_COMPONENTS, GL_MAX_TEXTURE_IMAGE_UNITS,
// GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS
// clang-format off
const GLchar *shader_preamble = "#version 300 es\n#define LAYER_COUNT ";
const GLchar *vertex_shader_source =
"\n"
"precision mediump int; \n"
"uniform vec4 uViewport; \n"
"uniform sampler2D uLayerTextures[LAYER_COUNT]; \n"
"uniform vec4 uLayerCrop[LAYER_COUNT]; \n"
"in vec2 vPosition; \n"
"in vec2 vTexCoords; \n"
"out vec2 fTexCoords[LAYER_COUNT]; \n"
"void main() { \n"
" for (int i = 0; i < LAYER_COUNT; i++) { \n"
" fTexCoords[i] = (uLayerCrop[i].xy + vTexCoords * uLayerCrop[i].zw) / \n"
" vec2(textureSize(uLayerTextures[i], 0)); \n"
" } \n"
" vec2 scaledPosition = uViewport.xy + vPosition * uViewport.zw; \n"
" gl_Position = vec4(scaledPosition * vec2(2.0) - vec2(1.0), 0.0, 1.0); \n"
"} \n";
const GLchar *fragment_shader_source =
"\n"
"precision mediump float; \n"
"uniform sampler2D uLayerTextures[LAYER_COUNT]; \n"
"uniform float uLayerAlpha[LAYER_COUNT]; \n"
"in vec2 fTexCoords[LAYER_COUNT]; \n"
"out vec4 oFragColor; \n"
"void main() { \n"
" vec3 color = vec3(0.0, 0.0, 0.0); \n"
" float alphaCover = 1.0; \n"
" for (int i = 0; i < LAYER_COUNT; i++) { \n"
" vec4 texSample = texture(uLayerTextures[i], fTexCoords[i]); \n"
" float a = texSample.a * uLayerAlpha[i]; \n"
" color += a * alphaCover * texSample.rgb; \n"
" alphaCover *= 1.0 - a; \n"
" if (alphaCover <= 0.5/255.0) \n"
" break; \n"
" } \n"
" oFragColor = vec4(color, 1.0 - alphaCover); \n"
"} \n";
// clang-format on
int i, ret = 1;
GLint max_texture_images, status;
AutoGLShader vertex_shader, fragment_shader;
AutoGLProgram program;
std::string shader_log;
glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &max_texture_images);
for (i = 1; i <= max_texture_images; i++) {
std::ostringstream layer_count_formatter;
layer_count_formatter << i;
std::string layer_count(layer_count_formatter.str());
const GLchar *shader_sources[3] = {shader_preamble, layer_count.c_str(),
NULL};
shader_sources[2] = vertex_shader_source;
vertex_shader = CompileAndCheckShader(GL_VERTEX_SHADER, 3, shader_sources,
ret ? &shader_log : NULL);
if (!vertex_shader.get()) {
if (ret)
ALOGE("Failed to make vertex shader:\n%s", shader_log.c_str());
break;
}
shader_sources[2] = fragment_shader_source;
fragment_shader = CompileAndCheckShader(
GL_FRAGMENT_SHADER, 3, shader_sources, ret ? &shader_log : NULL);
if (!fragment_shader.get()) {
if (ret)
ALOGE("Failed to make fragment shader:\n%s", shader_log.c_str());
break;
}
program = AutoGLProgram(glCreateProgram());
if (!program.get()) {
if (ret)
ALOGE("Failed to create program %s", GetGLError());
break;
}
glAttachShader(program.get(), vertex_shader.get());
glAttachShader(program.get(), fragment_shader.get());
glBindAttribLocation(program.get(), 0, "vPosition");
glBindAttribLocation(program.get(), 1, "vTexCoords");
glLinkProgram(program.get());
glDetachShader(program.get(), vertex_shader.get());
glDetachShader(program.get(), fragment_shader.get());
glGetProgramiv(program.get(), GL_LINK_STATUS, &status);
if (!status) {
if (ret) {
GLint log_length;
glGetProgramiv(program.get(), GL_INFO_LOG_LENGTH, &log_length);
std::string program_log(log_length, ' ');
glGetProgramInfoLog(program.get(), log_length, NULL, &program_log[0]);
ALOGE("Failed to link program: \n%s", program_log.c_str());
}
break;
}
ret = 0;
blend_programs->emplace_back(std::move(program));
}
return ret;
}