void StelQGLTextureBackend::loadFromPVR()
{
invariant();
//NOTE: We ignore bind options (mipmapping and filtering type) from params
// at the moment.
//
// We also ignore maximum texture size (QGLContext::bindTexture should
// fail if the texture is too large.
//
// QGLContext::bindTexture handles gl texture format for us.
QGLContext* context = prepareContextForLoading();
glTextureID = context->bindTexture(path);
if(glTextureID == 0)
{
errorOccured("loadFromPVR() failed to load a PVR file to a GL texture - "
"Maybe the file \"" + path + "\" is missing?");
invariant();
return;
}
// For some reason only LINEAR seems to work.
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
setTextureWrapping();
// This is an assumption; PVRTC can be either 4 or 2 bits per pixel - we assume the worse case.
pixelBytes = 0.5f;
completeLoading();
invariant();
}
//Image struct is copied (data is not - implicit sharing), so that
//ensureTextureSizeWithinLimits won't affect the original image.
void StelQGLTextureBackend::loadFromImage(QImage image)
{
invariant();
if(image.isNull())
{
errorOccured("loadFromImage(): Image data to load from is null. "
"Maybe the image failed to load from file?");
invariant();
return;
}
// Shrink if needed.
glEnsureTextureSizeWithinLimits(image);
if(!renderer->areNonPowerOfTwoTexturesSupported() &&
(!StelUtils::isPowerOfTwo(image.width()) ||
!StelUtils::isPowerOfTwo(image.height())))
{
errorOccured("loadFromImage(): Failed to load because the image has "
"non-power-of-two width and/or height while the renderer "
"backend only supports power-of-two dimensions");
invariant();
return;
}
GLint internalFormat = glGetTextureInternalFormat(image);
switch(internalFormat)
{
case GL_RGBA8: pixelBytes = 4.0f; break;
case GL_RGB8: pixelBytes = 3.0f; break;
case GL_LUMINANCE8_ALPHA8: pixelBytes = 2.0f; break;
case GL_LUMINANCE8: pixelBytes = 1.0f; break;
default: Q_ASSERT_X(false, Q_FUNC_INFO, "Unknown GL internal format for QImage");
}
QGLContext* context = prepareContextForLoading();
glTextureID = context->bindTexture(image, GL_TEXTURE_2D, internalFormat,
getTextureBindOptions(textureParams));
if(glTextureID == 0)
{
errorOccured("loadFromImage(): Failed to load an image to a GL texture");
invariant();
return;
}
setTextureWrapping();
completeLoading();
invariant();
}
void MenuState::createTexture()
{
glActiveTexture(GL_TEXTURE0);
glGenTextures(1, &m_Texture);
glBindTexture(GL_TEXTURE_2D, m_Texture);
setTextureWrapping();
setTextureFiltering();
glGenerateMipmap(GL_TEXTURE_2D);
auto textureData = loadTextureData();
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, m_TextureWidth, m_TextureHeight, 0, GL_RGB, GL_UNSIGNED_BYTE, textureData);
SOIL_free_image_data(textureData);
}