大家好,我正在尝试使用OpenGL加载纹理(法线贴图)。
GLuint loadTexture(const char* fileName) {
GLuint textureID;
glGenTextures(1, &textureID);
// load file - using core SDL library
SDL_Surface* tmpSurface;
tmpSurface = SDL_LoadBMP(fileName);
if (tmpSurface == nullptr) {
std::cout << "Error loading bitmap" << std::endl;
}
// bind texture and set parameters
glBindTexture(GL_TEXTURE_2D, textureID);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, tmpSurface->w, tmpSurface->h, 0,
GL_BGR, GL_UNSIGNED_BYTE, tmpSurface->pixels);
glGenerateMipmap(GL_TEXTURE_2D);
SDL_FreeSurface(tmpSurface);
return textureID;
}
而不是:
你有个主意吗?较深的颜色表示不起作用的颜色为32,有效的颜色为24]
使用SDL_ConvertSurfaceFormat
转换表面格式并加载转换后的曲面:
SDL_ConvertSurfaceFormat
当然,当用SDL_Surface* tmpSurface = SDL_LoadBMP(fileName);
SDL_Surface* formattedSurface = SDL_ConvertSurfaceFormat(
tmpSurface, SDL_PIXELFORMAT_RGBA8888, 0);
SDL_FreeSurface(tmpSurface);
// [...]
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, tmpSurface->w, tmpSurface->h, 0,
GL_RGBA, GL_UNSIGNED_BYTE, formattedSurface->pixels);
SDL_FreeSurface(formattedSurface);
指定二维纹理图像时,您可以评估format
的SDL_Surface
属性并设置适当的格式属性。