Mesa (master): mesa: fix unpack_ARGB1555_REV()

[Brian Paul]

Module: Mesa
Branch: master
Commit: e10942c8e966f7ea45f6b0d3782bbe38593796ae
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=e10942c8e966f7ea45f6b0d3782bbe38593796ae

Author: Brian Paul <brianp at vmware.com>
Date:   Wed Nov 30 20:35:02 2011 -0700

mesa: fix unpack_ARGB1555_REV()

We weren't doing the necessary byte swap.

v2: use same arithmetic as unpack_ARGB1555() to be consistent.

Reviewed-by: Michel Dänzer <michel at daenzer.net>

---

 src/mesa/main/format_unpack.c |    9 +++++----
 1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/mesa/main/format_unpack.c b/src/mesa/main/format_unpack.c
index 0411f5f..b4e4ac4 100644
--- a/src/mesa/main/format_unpack.c
+++ b/src/mesa/main/format_unpack.c
@@ -275,10 +275,11 @@ unpack_ARGB1555_REV(const void *src, GLfloat dst[][4], GLuint n)
    const GLushort *s = ((const GLushort *) src);
    GLuint i;
    for (i = 0; i < n; i++) {
-      dst[i][RCOMP] = UBYTE_TO_FLOAT( ((s[i] >>  7) & 0xf8) | ((s[i] >> 12) & 0x7) );
-      dst[i][GCOMP] = UBYTE_TO_FLOAT( ((s[i] >>  2) & 0xf8) | ((s[i] >>  7) & 0x7) );
-      dst[i][BCOMP] = UBYTE_TO_FLOAT( ((s[i] <<  3) & 0xf8) | ((s[i] >>  2) & 0x7) );
-      dst[i][ACOMP] = UBYTE_TO_FLOAT( ((s[i] >> 15) & 0x01) * 255 );
+      GLushort tmp = (s[i] << 8) | (s[i] >> 8); /* byteswap */
+      dst[i][RCOMP] = ((tmp >> 10) & 0x1f) * (1.0F / 31.0F);
+      dst[i][GCOMP] = ((tmp >>  5) & 0x1f) * (1.0F / 31.0F);
+      dst[i][BCOMP] = ((tmp >>  0) & 0x1f) * (1.0F / 31.0F);
+      dst[i][ACOMP] = ((tmp >> 15) & 0x01) * 1.0F;
    }
 }