diff options
| -rw-r--r-- | src/mesa/main/texcompress.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/src/mesa/main/texcompress.c b/src/mesa/main/texcompress.c index e71d0c411da..47ad3060523 100644 --- a/src/mesa/main/texcompress.c +++ b/src/mesa/main/texcompress.c @@ -263,6 +263,43 @@ _mesa_get_compressed_formats(struct gl_context *ctx, GLint *formats) else { n += 3; } + + /* The ES and desktop GL specs diverge here. + * + * In desktop OpenGL, the driver can perform online compression of + * uncompressed texture data. GL_NUM_COMPRESSED_TEXTURE_FORMATS and + * GL_COMPRESSED_TEXTURE_FORMATS give the application a list of + * formats that it could ask the driver to compress with some + * expectation of quality. The GL_ARB_texture_compression spec + * calls this "suitable for general-purpose usage." As noted + * above, this means GL_COMPRESSED_RGBA_S3TC_DXT1_EXT is not + * included in the list. + * + * In OpenGL ES, the driver never performs compression. + * GL_NUM_COMPRESSED_TEXTURE_FORMATS and + * GL_COMPRESSED_TEXTURE_FORMATS give the application a list of + * formats that the driver can receive from the application. It + * is the *complete* list of formats. The + * GL_EXT_texture_compression_s3tc spec says: + * + * "New State for OpenGL ES 2.0.25 and 3.0.2 Specifications + * + * The queries for NUM_COMPRESSED_TEXTURE_FORMATS and + * COMPRESSED_TEXTURE_FORMATS include + * COMPRESSED_RGB_S3TC_DXT1_EXT, + * COMPRESSED_RGBA_S3TC_DXT1_EXT, + * COMPRESSED_RGBA_S3TC_DXT3_EXT, and + * COMPRESSED_RGBA_S3TC_DXT5_EXT." + * + * Note that the addition is only to the OpenGL ES specification! + */ + if (_mesa_is_gles(ctx)) { + if (formats) { + formats[n++] = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT; + } else { + n += 1; + } + } } /* The GL_OES_compressed_ETC1_RGB8_texture spec says: |