view README.Porting @ 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 103760c3a5dc
children
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* Porting To A New Platform

  The first thing you have to do when porting to a new platform, is look at
include/SDL_platform.h and create an entry there for your operating system.
The standard format is __PLATFORM__, where PLATFORM is the name of the OS.
Ideally SDL_platform.h will be able to auto-detect the system it's building
on based on C preprocessor symbols.

There are two basic ways of building SDL at the moment:

1. The "UNIX" way:  ./configure; make; make install

   If you have a GNUish system, then you might try this.  Edit configure.in,
   take a look at the large section labelled:
	"Set up the configuration based on the target platform!"
   Add a section for your platform, and then re-run autogen.sh and build!

2. Using an IDE:

   If you're using an IDE or other non-configure build system, you'll probably
   want to create a custom SDL_config.h for your platform.  Edit SDL_config.h,
   add a section for your platform, and create a custom SDL_config_{platform}.h,
   based on SDL_config.h.minimal and SDL_config.h.in

   Add the top level include directory to the header search path, and then add
   the following sources to the project:
	src/*.c
	src/audio/*.c
	src/cdrom/*.c
	src/cpuinfo/*.c
	src/events/*.c
	src/file/*.c
	src/joystick/*.c
	src/stdlib/*.c
	src/thread/*.c
	src/timer/*.c
	src/video/*.c
	src/audio/disk/*.c
	src/audio/dummy/*.c
	src/video/dummy/*.c
	src/joystick/dummy/*.c
	src/cdrom/dummy/*.c
	src/thread/generic/*.c
	src/timer/dummy/*.c
	src/loadso/dummy/*.c


Once you have a working library without any drivers, you can go back to each
of the major subsystems and start implementing drivers for your platform.

If you have any questions, don't hesitate to ask on the SDL mailing list:
	http://www.libsdl.org/mailing-list.php

Enjoy!
	Sam Lantinga				(slouken@libsdl.org)