Mercurial > sdl-ios-xcode
view docs/man3/SDL_WasInit.3 @ 2359:b70b96e615d2 gsoc2008_iphone
These files are the OpenGL ES render driver. You should be able to use them on any platform that supports OpenGL ES -- not just iPhone. The driver is based off the OpenGL render driver.
There are a few differences between OpenGL and OpenGL ES that present difficulties for this driver:
- OpenGL ES does NOT support many pixel formats (for example, no GL_BGR). Also, when using texture functions format and internalFormat must be the same -- this means 32 bit packed formats like SDL_PIXELFORMAT_BGR888 cannot be automatically converted to GL_RGB (which is 24bpp).
- OpenGL ES doesn't have GL_PACK_ROW_LENGTH, which means data must be reformatted before uploading changes to dirty rects. This change has been added.
- OpenGL ES doesn't support paletted textures, though there is an extension. I'm looking into this.
Some other notable differences:
- OpenGL ES has an extension called GL_OES_draw_texture which allows for quicker 2D sprite-type drawing. I use this in GL_RenderCopy when it is available. The iPhone supports the extension, but the iPhone Simulator does not (presently).
- No glBegin() / glEnd() and no GL_QUADS! I'm using glDrawArrays with GL_TRIANGLE_STRIP instead!
author | Holmes Futrell <hfutrell@umail.ucsb.edu> |
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date | Thu, 17 Jul 2008 23:31:42 +0000 |
parents | 546f7c1eb755 |
children | 1238da4a7112 |
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.TH "SDL_WasInit" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" .SH "NAME" SDL_WasInit \- Check which subsystems are initialized .SH "SYNOPSIS" .PP \fB#include "SDL\&.h" .sp \fBUint32 \fBSDL_WasInit\fP\fR(\fBUint32 flags\fR); .SH "DESCRIPTION" .PP \fBSDL_WasInit\fP allows you to see which SDL subsytems have been \fIinitialized\fR\&. \fBflags\fR is a bitwise OR\&'d combination of the subsystems you wish to check (see \fI\fBSDL_Init\fP\fR for a list of subsystem flags)\&. .SH "RETURN VALUE" .PP \fBSDL_WasInit\fP returns a bitwised OR\&'d combination of the initialized subsystems\&. .SH "EXAMPLES" .PP .nf \f(CW /* Here are several ways you can use SDL_WasInit() */ /* Get init data on all the subsystems */ Uint32 subsystem_init; subsystem_init=SDL_WasInit(SDL_INIT_EVERYTHING); if(subsystem_init&SDL_INIT_VIDEO) printf("Video is initialized\&. "); else printf("Video is not initialized\&. "); /* Just check for one specfic subsystem */ if(SDL_WasInit(SDL_INIT_VIDEO)!=0) printf("Video is initialized\&. "); else printf("Video is not initialized\&. "); /* Check for two subsystems */ Uint32 subsystem_mask=SDL_INIT_VIDEO|SDL_INIT_AUDIO; if(SDL_WasInit(subsystem_mask)==subsystem_mask) printf("Video and Audio initialized\&. "); else printf("Video and Audio not initialized\&. "); \fR .fi .PP .SH "SEE ALSO" .PP \fI\fBSDL_Init\fP\fR, \fI\fBSDL_Subsystem\fP\fR ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00