• Sam Lantinga's avatar
    Mason Wheeler to sdl · b7844cd9
    Sam Lantinga authored
    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.
    
    --HG--
    extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%404226
    b7844cd9
SDL_video.c 85.5 KB