From 9ab896243cfdee7f6a626aceb26e4cb88bd4da2d Mon Sep 17 00:00:00 2001 From: Anuj Phogat Date: Fri, 16 Nov 2012 10:47:56 -0800 Subject: [PATCH] mesa: Fix GL_LUMINANCE handling for textures in glGetTexImage We need to rebase colors (ex: set G=B=0) when getting GL_LUMINANCE textures in following cases: 1. If the luminance texture is actually stored as rgba 2. If getting a luminance texture, but returning rgba 3. If getting an rgba texture, but returning luminance A similar fix was pushed by Brian Paul for uncompressed textures in commit: f5d0ced. Fixes https://bugs.freedesktop.org/show_bug.cgi?id=47220 Observed no regressions in piglit and ogles2conform due to this fix. This patch will cause failures in intel oglconform pxconv-gettex, pxstore-gettex and pxtrans-gettex test cases. The cause of failures is a bug in test cases. Expected luminance value is calculted incorrectly in test cases: L = R+G+B. V2: Set G = 0 when getting a RG texture but returning luminance. Note: This is a candidate for stable branches. Signed-off-by: Anuj Phogat Reviewed-by: Ian Romanick --- src/mesa/drivers/common/meta.c | 17 ++++++++++++--- src/mesa/main/texgetimage.c | 38 ++++++++++++++++++++++++---------- 2 files changed, 41 insertions(+), 14 deletions(-) diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c index 08bd899f861..d5e8af3c0a6 100644 --- a/src/mesa/drivers/common/meta.c +++ b/src/mesa/drivers/common/meta.c @@ -3685,6 +3685,7 @@ decompress_texture_image(struct gl_context *ctx, /* read pixels from renderbuffer */ { GLenum baseTexFormat = texImage->_BaseFormat; + GLenum destBaseFormat = _mesa_base_tex_format(ctx, destFormat); /* The pixel transfer state will be set to default values at this point * (see MESA_META_PIXEL_TRANSFER) so pixel transfer ops are effectively @@ -3693,9 +3694,19 @@ decompress_texture_image(struct gl_context *ctx, * returned as red and two-channel texture values are returned as * red/alpha. */ - if (baseTexFormat == GL_LUMINANCE || - baseTexFormat == GL_LUMINANCE_ALPHA || - baseTexFormat == GL_INTENSITY) { + if ((baseTexFormat == GL_LUMINANCE || + baseTexFormat == GL_LUMINANCE_ALPHA || + baseTexFormat == GL_INTENSITY) || + /* If we're reading back an RGB(A) texture (using glGetTexImage) as + * luminance then we need to return L=tex(R). + */ + ((baseTexFormat == GL_RGBA || + baseTexFormat == GL_RGB || + baseTexFormat == GL_RG) && + (destBaseFormat == GL_LUMINANCE || + destBaseFormat == GL_LUMINANCE_ALPHA || + destBaseFormat == GL_LUMINANCE_INTEGER_EXT || + destBaseFormat == GL_LUMINANCE_ALPHA_INTEGER_EXT))) { /* Green and blue must be zero */ _mesa_PixelTransferf(GL_GREEN_SCALE, 0.0f); _mesa_PixelTransferf(GL_BLUE_SCALE, 0.0f); diff --git a/src/mesa/main/texgetimage.c b/src/mesa/main/texgetimage.c index 2ccdcebd9f9..69067df9f5d 100644 --- a/src/mesa/main/texgetimage.c +++ b/src/mesa/main/texgetimage.c @@ -229,6 +229,8 @@ get_tex_rgba_compressed(struct gl_context *ctx, GLuint dimensions, const gl_format texFormat = _mesa_get_srgb_format_linear(texImage->TexFormat); const GLenum baseFormat = _mesa_get_format_base_format(texFormat); + const GLenum destBaseFormat = _mesa_base_tex_format(ctx, format); + GLenum rebaseFormat = GL_NONE; const GLuint width = texImage->Width; const GLuint height = texImage->Height; const GLuint depth = texImage->Depth; @@ -266,9 +268,31 @@ get_tex_rgba_compressed(struct gl_context *ctx, GLuint dimensions, } if (baseFormat == GL_LUMINANCE || + baseFormat == GL_INTENSITY || baseFormat == GL_LUMINANCE_ALPHA) { + /* If a luminance (or intensity) texture is read back as RGB(A), the + * returned value should be (L,0,0,1), not (L,L,L,1). Set rebaseFormat + * here to get G=B=0. + */ + rebaseFormat = texImage->_BaseFormat; + } + else if ((baseFormat == GL_RGBA || + baseFormat == GL_RGB || + baseFormat == GL_RG) && + (destBaseFormat == GL_LUMINANCE || + destBaseFormat == GL_LUMINANCE_ALPHA || + destBaseFormat == GL_LUMINANCE_INTEGER_EXT || + destBaseFormat == GL_LUMINANCE_ALPHA_INTEGER_EXT)) { + /* If we're reading back an RGB(A) texture as luminance then we need + * to return L=tex(R). Note, that's different from glReadPixels which + * returns L=R+G+B. + */ + rebaseFormat = GL_LUMINANCE_ALPHA; /* this covers GL_LUMINANCE too */ + } + + if (rebaseFormat) { _mesa_rebase_rgba_float(width * height, (GLfloat (*)[4]) tempImage, - baseFormat); + rebaseFormat); } srcRow = tempImage; @@ -332,7 +356,8 @@ get_tex_rgba_uncompressed(struct gl_context *ctx, GLuint dimensions, rebaseFormat = texImage->_BaseFormat; } else if ((texImage->_BaseFormat == GL_RGBA || - texImage->_BaseFormat == GL_RGB) && + texImage->_BaseFormat == GL_RGB || + texImage->_BaseFormat == GL_RG) && (destBaseFormat == GL_LUMINANCE || destBaseFormat == GL_LUMINANCE_ALPHA || destBaseFormat == GL_LUMINANCE_INTEGER_EXT || @@ -419,15 +444,6 @@ get_tex_rgba(struct gl_context *ctx, GLuint dimensions, transferOps |= IMAGE_CLAMP_BIT; } } - /* This applies to RGB, RGBA textures. if the format is either LUMINANCE - * or LUMINANCE ALPHA, luminance (L) is computed as L=R+G+B .we need to - * clamp the sum to [0,1]. - */ - else if ((format == GL_LUMINANCE || - format == GL_LUMINANCE_ALPHA) && - dataType == GL_UNSIGNED_NORMALIZED) { - transferOps |= IMAGE_CLAMP_BIT; - } if (_mesa_is_format_compressed(texImage->TexFormat)) { get_tex_rgba_compressed(ctx, dimensions, format, type,