opengl-playground/src/opengltexture.cpp

89 lines
2.3 KiB
C++

#include <opengl-playground/opengltexture.hpp>
#define STB_IMAGE_IMPLEMENTATION
#include <stb/stb_image.h>
#include <iostream>
#include <filesystem>
OpenGlTexture::OpenGlTexture(const std::string &texture_path)
{
glGenTextures(1, &this->texture);
glBindTexture(GL_TEXTURE_2D, this->texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
this->texture_path = texture_path;
this->blend = 1.0f;
}
OpenGlTexture::OpenGlTexture() : OpenGlTexture("")
{
}
OpenGlTexture::~OpenGlTexture()
{
glDeleteTextures(1, &this->texture);
}
void OpenGlTexture::setRGBDataFromBytes(unsigned int width, unsigned int height, char *buffer)
{
this->use();
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
glGenerateMipmap(GL_TEXTURE_2D);
}
void OpenGlTexture::loadFromImagePath(const std::string &base_directory)
{
int width, height, nrChannels;
std::filesystem::path base_path(base_directory);
std::filesystem::path tex_path(this->texture_path);
std::string filename;
if (tex_path.is_relative())
filename = base_path / tex_path;
else
filename = tex_path;
unsigned char *data = stbi_load(filename.c_str(), &width, &height, &nrChannels, 0);
if (data) {
GLenum format = 0;
if (nrChannels == 1)
format = GL_RED;
else if (nrChannels == 3)
format = GL_RGB;
else if (nrChannels == 4)
format = GL_RGBA;
this->use();
glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
glGenerateMipmap(GL_TEXTURE_2D);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
} else {
std::cout << "Texture loading of " << this->getPath() << " failed" << std::endl;
}
stbi_image_free(data);
}
void OpenGlTexture::use(unsigned int slot)
{
glActiveTexture(GL_TEXTURE0 + slot);
this->use();
}
void OpenGlTexture::use()
{
glBindTexture(GL_TEXTURE_2D, this->texture);
}
const std::string &OpenGlTexture::getPath()
{
return this->texture_path;
}