diff options
| -rw-r--r-- | src/mesa/state_tracker/st_cb_texture.c | 56 |
1 files changed, 44 insertions, 12 deletions
diff --git a/src/mesa/state_tracker/st_cb_texture.c b/src/mesa/state_tracker/st_cb_texture.c index e9c30cb5de5..a0dc016b334 100644 --- a/src/mesa/state_tracker/st_cb_texture.c +++ b/src/mesa/state_tracker/st_cb_texture.c @@ -31,6 +31,7 @@ #include "main/convolve.h" #endif #include "main/enums.h" +#include "main/fbobject.h" #include "main/formats.h" #include "main/image.h" #include "main/imports.h" @@ -1352,33 +1353,64 @@ fallback_copy_texsubimage(GLcontext *ctx, GLenum target, GLint level, } + +/** + * If the format of the src renderbuffer and the format of the dest + * texture are compatible (in terms of blitting), return a TGSI writemask + * to be used during the blit. + * If the src/dest are incompatible, return 0. + */ static unsigned -compatible_src_dst_formats(const struct gl_renderbuffer *src, +compatible_src_dst_formats(GLcontext *ctx, + const struct gl_renderbuffer *src, const struct gl_texture_image *dst) { - const GLenum srcFormat = _mesa_get_format_base_format(src->Format); - const GLenum dstLogicalFormat = _mesa_get_format_base_format(dst->TexFormat); + /* Get logical base formats for the src and dest. + * That is, use the user-requested formats and not the actual, device- + * chosen formats. + * For example, the user may have requested an A8 texture but the + * driver may actually be using an RGBA texture format. When we + * copy/blit to that texture, we only want to copy the Alpha channel + * and not the RGB channels. + * + * Similarly, when the src FBO was created an RGB format may have been + * requested but the driver actually chose an RGBA format. In that case, + * we don't want to copy the undefined Alpha channel to the dest texture + * (it should be 1.0). + */ + const GLenum srcFormat = _mesa_base_fbo_format(ctx, src->InternalFormat); + const GLenum dstFormat = _mesa_base_tex_format(ctx, dst->InternalFormat); - if (srcFormat == dstLogicalFormat) { + /** + * XXX when we have red-only and red/green renderbuffers we'll need + * to add more cases here (or implement a general-purpose routine that + * queries the existance of the R,G,B,A channels in the src and dest). + */ + if (srcFormat == dstFormat) { /* This is the same as matching_base_formats, which should * always pass, as it did previously. */ return TGSI_WRITEMASK_XYZW; } - else if (srcFormat == GL_RGBA && - dstLogicalFormat == GL_RGB) { - /* Add a single special case to cope with RGBA->RGB transfers, - * setting A to 1.0 to cope with situations where the RGB - * destination is actually stored as RGBA. + else if (srcFormat == GL_RGB && dstFormat == GL_RGBA) { + /* Make sure that A in the dest is 1. The actual src format + * may be RGBA and have undefined A values. + */ + return TGSI_WRITEMASK_XYZ; + } + else if (srcFormat == GL_RGBA && dstFormat == GL_RGB) { + /* Make sure that A in the dest is 1. The actual dst format + * may be RGBA and will need A=1 to provide proper alpha values + * when sampled later. */ - return TGSI_WRITEMASK_XYZ; /* A ==> 1.0 */ + return TGSI_WRITEMASK_XYZ; } else { if (ST_DEBUG & DEBUG_FALLBACK) debug_printf("%s failed for src %s, dst %s\n", __FUNCTION__, _mesa_lookup_enum_by_nr(srcFormat), - _mesa_lookup_enum_by_nr(dstLogicalFormat)); + _mesa_lookup_enum_by_nr(dstFormat)); /* Otherwise fail. */ @@ -1489,7 +1521,7 @@ st_copy_texsubimage(GLcontext *ctx, matching_base_formats = (_mesa_get_format_base_format(strb->Base.Format) == _mesa_get_format_base_format(texImage->TexFormat)); - format_writemask = compatible_src_dst_formats(&strb->Base, texImage); + format_writemask = compatible_src_dst_formats(ctx, &strb->Base, texImage); if (ctx->_ImageTransferState == 0x0) { |