Gosu::Bitmap Gosu::Texture::toBitmap(unsigned x, unsigned y, unsigned width, unsigned height) const
{
#ifdef GOSU_IS_IPHONE
throw std::logic_error("Texture::toBitmap not supported on iOS");
#else
Gosu::Bitmap fullTexture;
fullTexture.resize(size(), size());
glBindTexture(GL_TEXTURE_2D, name);
glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_UNSIGNED_BYTE, fullTexture.data());
Gosu::Bitmap bitmap;
bitmap.resize(width, height);
bitmap.insert(fullTexture, -int(x), -int(y));
return bitmap;
#endif
}
void Gosu::loadImageFile(Gosu::Bitmap& bitmap, Reader input)
{
stbi_io_callbacks callbacks;
callbacks.read = readCallback;
callbacks.skip = skipCallback;
callbacks.eof = eofCallback;
int x, y, n;
stbi_uc* bytes = stbi_load_from_callbacks(&callbacks, &input, &x, &y, &n, STBI_rgb_alpha);
if (bytes == 0) {
// TODO - stbi_failure_reason is not thread safe. Everything here should be wrapped in a mutex.
throw std::runtime_error("Cannot load image: " + std::string(stbi_failure_reason()));
}
bitmap.resize(x, y);
std::memcpy(bitmap.data(), bytes, x * y * sizeof(Gosu::Color));
stbi_image_free(bytes);
}