Mercurial > sdl-ios-xcode
annotate src/video/SDL_drawpoint.c @ 3485:e77a69aae239
Mason Wheeler to sdl
I updated SDL, and suddenly my SDL frames stopped working. They'd "initialize" full of gibberish, and I couldn't render anything to them. After a bit of digging, I found a problem: the renderer initialization routine in my SDL frame code wasn't getting called anymore.
procedure TSdlFrame.Paint;
begin
if SDL_SelectRenderer(FWindowID) = -1 then
CreateRenderer;
SDL_RenderPresent;
end;
function TSdlFrame.CreateRenderer: boolean;
const
pf: tagPIXELFORMATDESCRIPTOR = (nSize: sizeof(pf); nVersion: 1;
dwFlags: PFD_DRAW_TO_WINDOW or PFD_SUPPORT_OPENGL or PFD_DOUBLEBUFFER;
iPixelType: PFD_TYPE_RGBA; cColorBits: 24; cAlphaBits: 8;
iLayerType: PFD_MAIN_PLANE);
RENDERERS: array[TRendererType] of AnsiString = ('software', 'gdi', 'opengl', 'd3d');
var
pFormat: integer;
begin
if (SDL_SelectRenderer(FWindowID) = 0) then
begin
result := true;
Exit;
end;
if FRendererType = rtOpenGL then
begin
pFormat := ChoosePixelFormat(canvas.Handle, @pf);
if not SetPixelFormat(canvas.Handle, pFormat, @pf) then
outputDebugString(PChar(SysErrorMessage(GetLastError)));
if wglCreateContext(canvas.Handle) = 0 then
outputDebugString(PChar(SysErrorMessage(GetLastError)));
end;
if (SDL_CreateRenderer(FWindowID, SDL_RendererIndex(RENDERERS[FRendererType]), [sdlrPresentFlip3, sdlrAccelerated]) = 0) then
begin
SDL_ShowWindow(FWindowID);
assert(SDL_SetRenderDrawColor(0, 0, 0, 255) = 0);
FFlags := SDL_GetWindowFlags(FWindowID);
if assigned(FOnAvailable) then
FOnAvailable(self);
end
else outputDebugString(pChar(format('SDL_CreateRenderer failed: %s', [sdl_GetError])));
result := SDL_SelectRenderer(FWindowID) = 0;
end;
This is a critical issue. The Paint method gets called when the control receives a WM_PAINT message from Windows. I can't create the renderer before then, or it will fail and cause trouble. And when I do create it, it needs to be created with certain parameters. So imagine my surprise when I started debugging into the DLL and found that SDL_SelectRenderer was trying to be "helpful" by creating the renderer for me if it didn't already exist! Now not only does my initialization code not get called, I end up with the wrong renderer and so things don't render as expected when I try to use the window.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Tue, 24 Nov 2009 04:48:12 +0000 |
| parents | 210e209b87cc |
| children | 0267b8b1595c |
| rev | line source |
|---|---|
| 2901 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
| 3 Copyright (C) 1997-2009 Sam Lantinga | |
| 4 | |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Lesser General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2.1 of the License, or (at your option) any later version. | |
| 9 | |
| 10 This library is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 Lesser General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Lesser General Public | |
| 16 License along with this library; if not, write to the Free Software | |
| 17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
| 18 | |
| 19 Sam Lantinga | |
| 20 slouken@libsdl.org | |
| 21 */ | |
| 22 #include "SDL_config.h" | |
| 23 | |
| 24 #include "SDL_draw.h" | |
| 25 | |
| 26 | |
| 27 int | |
| 28 SDL_DrawPoint(SDL_Surface * dst, int x, int y, Uint32 color) | |
| 29 { | |
| 30 /* This function doesn't work on surfaces < 8 bpp */ | |
| 31 if (dst->format->BitsPerPixel < 8) { | |
| 3160 | 32 SDL_SetError("SDL_DrawPoint(): Unsupported surface format"); |
| 2901 | 33 return (-1); |
| 34 } | |
| 35 | |
| 36 /* Perform clipping */ | |
| 37 if (x < dst->clip_rect.x || y < dst->clip_rect.y || | |
| 38 x >= (dst->clip_rect.x + dst->clip_rect.w) || | |
| 39 y >= (dst->clip_rect.y + dst->clip_rect.h)) { | |
| 40 return 0; | |
| 41 } | |
| 42 | |
| 43 switch (dst->format->BytesPerPixel) { | |
| 44 case 1: | |
| 45 DRAW_FASTSETPIXEL1(x, y); | |
| 46 break; | |
| 47 case 2: | |
| 48 DRAW_FASTSETPIXEL2(x, y); | |
| 49 break; | |
| 50 case 3: | |
| 51 SDL_Unsupported(); | |
| 52 return -1; | |
| 53 case 4: | |
| 54 DRAW_FASTSETPIXEL4(x, y); | |
| 55 break; | |
| 56 } | |
| 57 return 0; | |
| 58 } | |
| 59 | |
| 60 /* vi: set ts=4 sw=4 expandtab: */ |