Mercurial > sdl-ios-xcode
view src/video/Xext/extensions/xf86dga1str.h @ 1544:ab1e4c41ab71
Fixed bug #33
Mike Frysinger wrote:
> with libsdl-1.2.9, some games (like bomberclone) started
> segfaulting in Gentoo
[...snip...]
> the last change in the last hunk:
[...snip...]
> if i change the statement to read:
> (table[which].blit_features & GetBlitFeatures()) == GetBlitFeatures()
> bomberclone no longer segfaults on my box
Alex Volkov wrote:
> The test "(table[which].blit_features & GetBlitFeatures()) ==
> table[which].blit_features)" is correct, and the previous
> "(table[which].cpu_mmx == SDL_HasMMX())" was actually broken.
I think there is potentially a slightly different cause of the above problem.
During the introduction of the Altivec code, the blit_table struct field
'alpha' got changed from a straightforward enum to a bitmask, which makes
perfect sense by itself. However, now the table driven blitter selection code
in SDL_CalculateBlitN() can choose the wrong blitters when searching for a
NO_ALPHA blitter because of the following code:
int a_need = 0;
...
(a_need & table[which].alpha) == a_need &&
When searching through the normal_blit_2[] table, a SET_ALPHA blitter (like
Blit_RGB565_ARGB8888) can now be selected instead of a NO_ALPHA one, causing
alpha channel bits to appear in a non-alpha destination surface. I suppose this
could theoretically be an indirect cause of the segfault mentioned above.
I *think* this can be fixed by changing to
int a_need = NO_ALPHA;
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 15 Mar 2006 15:47:49 +0000 |
parents | eadc0746dfaf |
children | 782fd950bd46 |
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/* $XFree86: xc/include/extensions/xf86dga1str.h,v 1.2 1999/05/03 12:15:37 dawes Exp $ */ /* Copyright (c) 1995 Jon Tombs Copyright (c) 1995 XFree86 Inc. */ #ifndef _XF86DGASTR1_H_ #define _XF86DGASTR1_H_ typedef struct _XF86DGAQueryVersion { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_DGAQueryVersion */ CARD16 length B16; } xXF86DGAQueryVersionReq; #define sz_xXF86DGAQueryVersionReq 4 typedef struct { BYTE type; /* X_Reply */ BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD16 majorVersion B16; /* major version of DGA protocol */ CARD16 minorVersion B16; /* minor version of DGA protocol */ CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; CARD32 pad6 B32; } xXF86DGAQueryVersionReply; #define sz_xXF86DGAQueryVersionReply 32 typedef struct _XF86DGAGetVideoLL { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGAGetVideoLL */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAGetVideoLLReq; #define sz_xXF86DGAGetVideoLLReq 8 typedef struct _XF86DGAInstallColormap{ CARD8 reqType; CARD8 dgaReqType; CARD16 length B16; CARD16 screen B16; CARD16 pad2; CARD32 id B32; /* colormap. */ } xXF86DGAInstallColormapReq; #define sz_xXF86DGAInstallColormapReq 12 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 offset B32; CARD32 width B32; CARD32 bank_size B32; CARD32 ram_size B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAGetVideoLLReply; #define sz_xXF86DGAGetVideoLLReply 32 typedef struct _XF86DGADirectVideo { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGADirectVideo */ CARD16 length B16; CARD16 screen B16; CARD16 enable B16; } xXF86DGADirectVideoReq; #define sz_xXF86DGADirectVideoReq 8 typedef struct _XF86DGAGetViewPortSize { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGAGetViewPort */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAGetViewPortSizeReq; #define sz_xXF86DGAGetViewPortSizeReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 width B32; CARD32 height B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAGetViewPortSizeReply; #define sz_xXF86DGAGetViewPortSizeReply 32 typedef struct _XF86DGASetViewPort { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGASetViewPort */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; CARD32 x B32; CARD32 y B32; } xXF86DGASetViewPortReq; #define sz_xXF86DGASetViewPortReq 16 typedef struct _XF86DGAGetVidPage { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGAGetVidPage */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAGetVidPageReq; #define sz_xXF86DGAGetVidPageReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 vpage B32; CARD32 pad B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAGetVidPageReply; #define sz_xXF86DGAGetVidPageReply 32 typedef struct _XF86DGASetVidPage { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGASetVidPage */ CARD16 length B16; CARD16 screen B16; CARD16 vpage B16; } xXF86DGASetVidPageReq; #define sz_xXF86DGASetVidPageReq 8 typedef struct _XF86DGAQueryDirectVideo { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_DGAQueryVersion */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAQueryDirectVideoReq; #define sz_xXF86DGAQueryDirectVideoReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 flags B32; CARD32 pad B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAQueryDirectVideoReply; #define sz_xXF86DGAQueryDirectVideoReply 32 typedef struct _XF86DGAViewPortChanged { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_DGAQueryVersion */ CARD16 length B16; CARD16 screen B16; CARD16 n B16; } xXF86DGAViewPortChangedReq; #define sz_xXF86DGAViewPortChangedReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 result B32; CARD32 pad B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAViewPortChangedReply; #define sz_xXF86DGAViewPortChangedReply 32 #endif /* _XF86DGASTR1_H_ */