[Mesa-dev] [PATCH v2] mesa: fix ARB_copy_image internal format check
Sean Burke
leftmostcat at gmail.com
Sat Mar 7 12:16:06 PST 2015
On Sat, Mar 7, 2015 at 12:06 PM, Jason Ekstrand <jason at jlekstrand.net>
wrote:
>
> On Mar 7, 2015 10:57 AM, "Sean Burke" <leftmostcat at gmail.com> wrote:
> >
> > The memory layout of compatible internal formats may differ in bytes per
> > block, so TexFormat is not a reliable measure of compatibility.
> Additionally,
> > the current check allows compressed textures of the same block size to
> be used,
> > which is in violation of the spec.
>
> Could you please be more specific about exactly when the old code fails.
>
One example I was finding in running piglit tests was that GL_INVALID_VALUE
was being set when the formats to be converted were GL_RGB8 and GL_RGB8UI.
TexFormat refers specifically to the actual memory layout which mesa has
chosen for the texture, not to the internal format specified by the user,
and there's no guarantee that the bytes-per-block of the memory layout
matches the internal format. GL_RGB8 was being backed by B8G8R8X8, even
though its internal format is still 3 bytes.
Additionally, the previous code indicated that textures with two different
compressed formats were compatible if block size was identical. According
to the spec, this is incorrect. Different texture formats are only
compatible if they're compatible texture view-wise or if one is compressed
and the other is uncompressed and they are listed in the given table.
In writing this out, I've discovered that I do have a bug in
copy_format_compatible() (view compatibility should be checked second,
immediately after checking if the formats are equal, to account for
view-compatible compressed formats), which I'll correct with a v3.
> > v2: Use a switch instead of array iteration for block class and show the
> > correct GL error when internal formats are mismatched.
> > ---
> > src/mesa/main/copyimage.c | 112
> +++++++++++++++++++++++++++++++++++++---------
> > 1 file changed, 91 insertions(+), 21 deletions(-)
> >
> > diff --git a/src/mesa/main/copyimage.c b/src/mesa/main/copyimage.c
> > index 455929d..eaedaa6 100644
> > --- a/src/mesa/main/copyimage.c
> > +++ b/src/mesa/main/copyimage.c
> > @@ -33,6 +33,12 @@
> > #include "texobj.h"
> > #include "fbobject.h"
> > #include "textureview.h"
> > +#include "glformats.h"
> > +
> > +enum mesa_block_class {
> > + BLOCK_CLASS_128_BITS,
> > + BLOCK_CLASS_64_BITS
> > +};
> >
> > static bool
> > prepare_target(struct gl_context *ctx, GLuint name, GLenum *target, int
> level,
> > @@ -253,6 +259,85 @@ check_region_bounds(struct gl_context *ctx,
> > struct gl_texture_image *tex_image,
> > return true;
> > }
> >
> > +static bool
> > +compressed_format_compatible(struct gl_context *ctx,
> > + GLenum compressedFormat, GLenum
> otherFormat)
> > +{
> > + enum mesa_block_class compressedClass, otherClass;
> > +
> > + /* Two different compressed formats are never compatible. */
> > + if (_mesa_is_compressed_format(ctx, otherFormat)) {
> > + return false;
> > + }
> > +
> > + switch (compressedFormat) {
> > + case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
> > + case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
> > + case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
> > + case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
> > + case GL_COMPRESSED_RG_RGTC2:
> > + case GL_COMPRESSED_SIGNED_RG_RGTC2:
> > + case GL_COMPRESSED_RGBA_BPTC_UNORM:
> > + case GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM:
> > + case GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT:
> > + case GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT:
> > + compressedClass = BLOCK_CLASS_128_BITS;
> > + break;
> > + case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
> > + case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
> > + case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
> > + case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
> > + case GL_COMPRESSED_RED_RGTC1:
> > + case GL_COMPRESSED_SIGNED_RED_RGTC1:
> > + compressedClass = BLOCK_CLASS_64_BITS;
> > + break;
> > + default:
> > + return false;
> > + }
> > +
> > + switch (otherFormat) {
> > + case GL_RGBA32UI:
> > + case GL_RGBA32I:
> > + case GL_RGBA32F:
> > + otherClass = BLOCK_CLASS_128_BITS;
> > + break;
> > + case GL_RGBA16F:
> > + case GL_RG32F:
> > + case GL_RGBA16UI:
> > + case GL_RG32UI:
> > + case GL_RGBA16I:
> > + case GL_RG32I:
> > + case GL_RGBA16:
> > + case GL_RGBA16_SNORM:
> > + otherClass = BLOCK_CLASS_64_BITS;
> > + break;
> > + default:
> > + return false;
> > + }
> > +
> > + return compressedClass == otherClass;
> > +}
>
> For compressed formats this should be the same as doing a bits-per-block
> check. Why do we need all this?
>
Given that the spec gives an exhaustive list of all compatible
compressed/uncompressed formats, rather than indicating that it's valid for
any compressed format of a given block size, I feel it's best to be
specific. A similar approach is taken for texture view compatibility, so it
makes sense to me that we would take the same exhaustive approach here.
> > +static bool
> > +copy_format_compatible(struct gl_context *ctx,
> > + GLenum srcFormat, GLenum dstFormat)
> > +{
> > + if (srcFormat == dstFormat) {
> > + return true;
> > + }
> > + else if (_mesa_is_compressed_format(ctx, srcFormat)) {
> > + return compressed_format_compatible(ctx, srcFormat, dstFormat);
> > + }
> > + else if (_mesa_is_compressed_format(ctx, dstFormat)) {
> > + return compressed_format_compatible(ctx, dstFormat, srcFormat);
> > + }
> > + else {
> > + return _mesa_texture_view_compatible_format(ctx,
> > + srcFormat,
> > + dstFormat);
> > + }
> > +}
> > +
> > void GLAPIENTRY
> > _mesa_CopyImageSubData(GLuint srcName, GLenum srcTarget, GLint srcLevel,
> > GLint srcX, GLint srcY, GLint srcZ,
> > @@ -265,7 +350,7 @@ _mesa_CopyImageSubData(GLuint srcName, GLenum
> > srcTarget, GLint srcLevel,
> > struct gl_texture_object *srcTexObj, *dstTexObj;
> > struct gl_texture_image *srcTexImage, *dstTexImage;
> > GLuint src_bw, src_bh, dst_bw, dst_bh;
> > - int i, srcNewZ, dstNewZ, Bpt;
> > + int i, srcNewZ, dstNewZ;
> >
> > if (MESA_VERBOSE & VERBOSE_API)
> > _mesa_debug(ctx, "glCopyImageSubData(%u, %s, %d, %d, %d, %d, "
> > @@ -306,15 +391,6 @@ _mesa_CopyImageSubData(GLuint srcName, GLenum
> > srcTarget, GLint srcLevel,
> > goto cleanup;
> > }
> >
> > - /* Very simple sanity check. This is sufficient if one of the
> textures
> > - * is compressed. */
> > - Bpt = _mesa_get_format_bytes(srcTexImage->TexFormat);
> > - if (_mesa_get_format_bytes(dstTexImage->TexFormat) != Bpt) {
> > - _mesa_error(ctx, GL_INVALID_VALUE,
> > - "glCopyImageSubData(internalFormat mismatch)");
> > - goto cleanup;
> > - }
> > -
> > if (!check_region_bounds(ctx, srcTexImage, srcX, srcY, srcZ,
> > srcWidth, srcHeight, srcDepth, "src"))
> > goto cleanup;
> > @@ -324,17 +400,11 @@ _mesa_CopyImageSubData(GLuint srcName, GLenum
> > srcTarget, GLint srcLevel,
> > (srcHeight / src_bh) * dst_bh, srcDepth,
> "dst"))
> > goto cleanup;
> >
> > - if (_mesa_is_format_compressed(srcTexImage->TexFormat)) {
> > - /* XXX: Technically, we should probaby do some more specific
> checking
> > - * here. However, this should be sufficient for all compressed
> > - * formats that mesa supports since it is a direct memory copy.
> > - */
> > - } else if (_mesa_is_format_compressed(dstTexImage->TexFormat)) {
> > - } else if (_mesa_texture_view_compatible_format(ctx,
> > -
> srcTexImage->InternalFormat,
> > -
> > dstTexImage->InternalFormat)) {
> > - } else {
> > - return; /* Error logged by _mesa_texture_view_compatible_format */
> > + if (!copy_format_compatible(ctx, srcTexImage->InternalFormat,
> > + dstTexImage->InternalFormat)) {
> > + _mesa_error(ctx, GL_INVALID_OPERATION,
> > + "glCopyImageSubData(internalFormat mismatch)");
> > + goto cleanup;
> > }
> >
> > for (i = 0; i < srcDepth; ++i) {
> > --
> > 2.1.0
> > _______________________________________________
> > mesa-dev mailing list
> > mesa-dev at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/mesa-dev
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/mesa-dev/attachments/20150307/b70c94b8/attachment.html>
More information about the mesa-dev
mailing list