void
WebGLTexture::GenerateMipmap(TexTarget texTarget)
{
const TexImageTarget imageTarget = (texTarget == LOCAL_GL_TEXTURE_2D)
? LOCAL_GL_TEXTURE_2D
: LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_X;
if (!IsMipmapRangeValid())
{
return mContext->ErrorInvalidOperation("generateMipmap: Texture does not have a valid mipmap range.");
}
if (!HasImageInfoAt(imageTarget, EffectiveBaseMipmapLevel()))
{
return mContext->ErrorInvalidOperation("generateMipmap: Level zero of texture is not defined.");
}
if (!mContext->IsWebGL2() && !IsFirstImagePowerOfTwo())
return mContext->ErrorInvalidOperation("generateMipmap: Level zero of texture does not have power-of-two width and height.");
TexInternalFormat internalformat = ImageInfoAt(imageTarget, 0).EffectiveInternalFormat();
if (IsTextureFormatCompressed(internalformat))
return mContext->ErrorInvalidOperation("generateMipmap: Texture data at level zero is compressed.");
if (mContext->IsExtensionEnabled(WebGLExtensionID::WEBGL_depth_texture) &&
(IsGLDepthFormat(internalformat) || IsGLDepthStencilFormat(internalformat)))
{
return mContext->ErrorInvalidOperation("generateMipmap: "
"A texture that has a base internal format of "
"DEPTH_COMPONENT or DEPTH_STENCIL isn't supported");
}
if (!AreAllLevel0ImageInfosEqual())
return mContext->ErrorInvalidOperation("generateMipmap: The six faces of this cube map have different dimensions, format, or type.");
SetGeneratedMipmap();
mContext->MakeContextCurrent();
gl::GLContext* gl = mContext->gl;
if (gl->WorkAroundDriverBugs()) {
// bug 696495 - to work around failures in the texture-mips.html test on various drivers, we
// set the minification filter before calling glGenerateMipmap. This should not carry a significant performance
// overhead so we do it unconditionally.
//
// note that the choice of GL_NEAREST_MIPMAP_NEAREST really matters. See Chromium bug 101105.
gl->fTexParameteri(texTarget.get(), LOCAL_GL_TEXTURE_MIN_FILTER, LOCAL_GL_NEAREST_MIPMAP_NEAREST);
gl->fGenerateMipmap(texTarget.get());
gl->fTexParameteri(texTarget.get(), LOCAL_GL_TEXTURE_MIN_FILTER, MinFilter().get());
} else {
gl->fGenerateMipmap(texTarget.get());
}
}
static inline bool
IsValidFBOTextureDepthStencilFormat(GLenum internalformat)
{
return IsGLDepthStencilFormat(internalformat);
}
