Mercurial > sdl-ios-xcode
view src/video/bwindow/SDL_BView.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 | d910939febfa |
children | 782fd950bd46 c121d94672cb 678576473849 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" #ifndef _SDL_BView_h #define _SDL_BView_h /* This is the event handling and graphics update portion of SDL_BWin */ extern "C" { #include "../../events/SDL_events_c.h" }; class SDL_BView : public BView { public: SDL_BView(BRect frame) : BView(frame, "SDL View", B_FOLLOW_ALL_SIDES, (B_WILL_DRAW|B_FRAME_EVENTS)) { image = NULL; xoff = yoff = 0; SetViewColor(0,0,0,0); SetHighColor(0,0,0,0); } virtual ~SDL_BView() { SetBitmap(NULL); } /* Set drawing offsets for fullscreen mode */ virtual void SetXYOffset(int x, int y) { xoff = x; yoff = y; } virtual void GetXYOffset(int &x, int &y) { x = xoff; y = yoff; } /* The view changed size. If it means we're in fullscreen, we * draw a nice black box in the entire view to get black borders. */ virtual void FrameResized(float width, float height) { BRect bounds; bounds.top = bounds.left = 0; bounds.right = width; bounds.bottom = height; /* Fill the entire view with black */ FillRect(bounds, B_SOLID_HIGH); /* And if there's an image, redraw it. */ if( image ) { bounds = image->Bounds(); Draw(bounds); } } /* Drawing portion of this complete breakfast. :) */ virtual void SetBitmap(BBitmap *bitmap) { if ( image ) { delete image; } image = bitmap; } virtual void Draw(BRect updateRect) { if ( image ) { if(xoff || yoff) { BRect dest; dest.top = updateRect.top + yoff; dest.left = updateRect.left + xoff; dest.bottom = updateRect.bottom + yoff; dest.right = updateRect.right + xoff; DrawBitmap(image, updateRect, dest); } else { DrawBitmap(image, updateRect, updateRect); } } } virtual void DrawAsync(BRect updateRect) { if(xoff || yoff) { BRect dest; dest.top = updateRect.top + yoff; dest.left = updateRect.left + xoff; dest.bottom = updateRect.bottom + yoff; dest.right = updateRect.right + xoff;; DrawBitmapAsync(image, updateRect, dest); } else { DrawBitmapAsync(image, updateRect, updateRect); } } private: BBitmap *image; int xoff, yoff; }; #endif /* _SDL_BView_h */