swrast: Make a teximage's stored RowStride be in terms of bytes per row.

For hardware drivers with pitch alignment requirements, a
non-power-of-two-sized texture format won't end up being an integer number
of pixels per row.  Also, avoids having to change our units between
MapTextureImage's rowStride and swrast's RowStride.

This doesn't fully convert the compressed texel fetch path, but does make
sure we don't drop any bits (not that we'd expect to).

Reviewed-by: Kenneth Graunke <[email protected]>
Reviewed-by: Brian Paul <[email protected]>

1 files changed, 10 insertions, 2 deletions

diff --git a/src/mesa/swrast/s_context.h b/src/mesa/swrast/s_context.h
index 7b3c740c1ca..38015483597 100644
--- a/src/mesa/swrast/s_context.h
+++ b/src/mesa/swrast/s_context.h
@@ -138,8 +138,16 @@ struct swrast_texture_image
    /** used for mipmap LOD computation */
    GLfloat WidthScale, HeightScale, DepthScale;
 
-   /** These fields only valid when texture memory is mapped */
-   GLint RowStride;		/**< Padded width in units of texels */
+   /**
+    * Byte stride between rows in ImageSlices.
+    *
+    * For compressed textures, this is the byte stride between one row of
+    * blocks and the next row of blocks.
+    *
+    * Only valid while one of the ImageSlices is mapped, and must be the same
+    * between all slices.
+    */
+   GLint RowStride;
    void **ImageSlices;          /**< if 3D texture: array [Depth] of offsets to
                                      each 2D slice in 'Data', in texels */
    GLubyte *Map;		/**< Pointer to mapped image memory */