From Jannik Heller, "Here is a patch for the S3TC capability check.

On a Intel HD graphics Linux system with Mesa 10.1.3, I found that osg's Extensions::isTextureCompressionS3TCSupported() returned false, even though S3TC compressed textures *are* in fact working. I tested this by loading and rendering various DXT1, DXT3 and DXT5 compressed textures in the OSG.

"glxinfo | grep s3tc" gives:
    GL_S3_s3tc

Note, if I install the package "libtxc-dxtn-s2tc0", I get in addition:

glxinfo | grep s3tc
    GL_EXT_texture_compression_s3tc
    GL_S3_s3tc

However, S3TC compressed textures worked correctly within the OSG even without libtxc-dxtn-s2tc0 installed.

I'm not sure what the differences between these extensions are, but based on the description at https://www.opengl.org/registry/specs/S3/s3tc.txt I would assume that both will work for OSG's purposes. The attached patch changes isTextureCompressionS3TCSupported() to accept either extension."


git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/trunk@15035 16af8721-9629-0410-8352-f15c8da7e697
This commit is contained in:
Robert Osfield 2015-07-31 13:44:39 +00:00
parent 55d36b544b
commit 42884e7600

View File

@ -807,7 +807,7 @@ GLExtensions::GLExtensions(unsigned int contextID)
isTextureFilterAnisotropicSupported = isGLExtensionSupported(contextID,"GL_EXT_texture_filter_anisotropic");
isTextureSwizzleSupported = isGLExtensionSupported(contextID,"GL_ARB_texture_swizzle");
isTextureCompressionARBSupported = builtInSupport || isGLExtensionOrVersionSupported(contextID,"GL_ARB_texture_compression", 1.3f);
isTextureCompressionS3TCSupported = isGLExtensionSupported(contextID,"GL_EXT_texture_compression_s3tc");
isTextureCompressionS3TCSupported = isGLExtensionSupported(contextID,"GL_EXT_texture_compression_s3tc") || isGLExtensionSupported(contextID, "GL_S3_s3tc");
isTextureCompressionPVRTC2BPPSupported = isGLExtensionSupported(contextID,"GL_IMG_texture_compression_pvrtc");
isTextureCompressionPVRTC4BPPSupported = isTextureCompressionPVRTC2BPPSupported;//covered by same extension
isTextureCompressionETCSupported = isGLExtensionSupported(contextID,"GL_OES_compressed_ETC1_RGB8_texture");