Michael Abbott : wined3d: Remove division from inner loop.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 2e119a2718ccb3cdf32277c5985bc2bb55c52a34
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=2e119a2718ccb3cdf32277c5985bc2bb55c52a34

Author: Michael Abbott <michael at araneidae.co.uk>
Date:   Tue Jun 16 16:20:05 2009 +0100

wined3d: Remove division from inner loop.

---

 dlls/wined3d/surface.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/dlls/wined3d/surface.c b/dlls/wined3d/surface.c
index eedc257..400a652 100644
--- a/dlls/wined3d/surface.c
+++ b/dlls/wined3d/surface.c
@@ -2461,9 +2461,11 @@ static HRESULT d3dfmt_convert_surface(const BYTE *src, BYTE *dst, UINT pitch, UI
 
                 for (x = 0; x < width; ++x)
                 {
-                    /* The depth data is normalized, so needs to be scaled, the stencil data isn't. */
-                    WORD d15 = source[x] & 0xfffe;
-                    DWORD d24 = d15 * 0x100 + (d15 * 0xff80 + 0x3fff80) / 0x7fff00;
+                    /* The depth data is normalized, so needs to be scaled,
+                     * the stencil data isn't.  Scale depth data by
+                     *      (2^24-1)/(2^15-1) ~~ (2^9 + 2^-6). */
+                    WORD d15 = source[x] >> 1;
+                    DWORD d24 = (d15 << 9) + (d15 >> 6);
                     dest[x] = (d24 << 8) | (source[x] & 0x1);
                 }
             }