Mercurial > sdl-ios-xcode
view docs/html/video.html @ 641:df178851293b
Date: 28 Jun 2003 22:42:52 +0100
From: Alan Swanson
Subject: Re: [SDL] New XFree 4.3 Video Mode Patch
I have a wee amendment that moves the qsort in set_best_resolution
to only occur after failing to find an exact match only. This would
make absolutely sure we get a user set mode.
While I've never had any problems for my normal resolutions (1280x1024,
1024x768, 800x600 & 640,480) while closely examining the output from
qsort I've noticed it doesn't seem to sort the modes fully. These is
one definite wrong at 1152x768 and a few that just look wrong to me.
From a program (attached) I made to examine this more easily. X has
sorted its mode list using the same method as ours (plus frequency),
and our user modes get inserted without any other movement.
On the patch I've made I've also changed cmpmodes to sort on vertical
resolution and then horizontal. Ie vertical is now most significant
bit.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 28 Jun 2003 21:52:26 +0000 |
parents | e5bc29de3f0a |
children | 355632dca928 |
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line source
<HTML ><HEAD ><TITLE >Video</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.64 "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="SDL Reference" HREF="reference.html"><LINK REL="PREVIOUS" TITLE="SDL_GetError" HREF="sdlgeterror.html"><LINK REL="NEXT" TITLE="SDL_GetVideoSurface" HREF="sdlgetvideosurface.html"><META NAME="KEYWORD" CONTENT="video"><META NAME="KEYWORD" CONTENT="function"></HEAD ><BODY CLASS="CHAPTER" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="sdlgeterror.html" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlgetvideosurface.html" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="VIDEO" >Chapter 6. Video</A ></H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT ><A HREF="sdlgetvideosurface.html" >SDL_GetVideoSurface</A > — returns a pointer to the current display surface</DT ><DT ><A HREF="sdlgetvideoinfo.html" >SDL_GetVideoInfo</A > — returns a pointer to information about the video hardware</DT ><DT ><A HREF="sdlvideodrivername.html" >SDL_VideoDriverName</A > — Obtain the name of the video driver</DT ><DT ><A HREF="sdllistmodes.html" >SDL_ListModes</A > — Returns a pointer to an array of available screen dimensions for the given format and video flags</DT ><DT ><A HREF="sdlvideomodeok.html" >SDL_VideoModeOK</A > — Check to see if a particular video mode is supported.</DT ><DT ><A HREF="sdlsetvideomode.html" >SDL_SetVideoMode</A > — Set up a video mode with the specified width, height and bits-per-pixel.</DT ><DT ><A HREF="sdlupdaterect.html" >SDL_UpdateRect</A > — Makes sure the given area is updated on the given screen.</DT ><DT ><A HREF="sdlupdaterects.html" >SDL_UpdateRects</A > — Makes sure the given list of rectangles is updated on the given screen.</DT ><DT ><A HREF="sdlflip.html" >SDL_Flip</A > — Swaps screen buffers</DT ><DT ><A HREF="sdlsetcolors.html" >SDL_SetColors</A > — Sets a portion of the colormap for the given 8-bit surface.</DT ><DT ><A HREF="sdlsetpalette.html" >SDL_SetPalette</A > — Sets the colors in the palette of an 8-bit surface.</DT ><DT ><A HREF="sdlsetgamma.html" >SDL_SetGamma</A > — Sets the color gamma function for the display</DT ><DT ><A HREF="sdlgetgammaramp.html" >SDL_GetGammaRamp</A > — Gets the color gamma lookup tables for the display</DT ><DT ><A HREF="sdlsetgammaramp.html" >SDL_SetGammaRamp</A > — Sets the color gamma lookup tables for the display</DT ><DT ><A HREF="sdlmaprgb.html" >SDL_MapRGB</A > — Map a RGB color value to a pixel format.</DT ><DT ><A HREF="sdlmaprgba.html" >SDL_MapRGBA</A > — Map a RGBA color value to a pixel format.</DT ><DT ><A HREF="sdlgetrgb.html" >SDL_GetRGB</A > — Get RGB values from a pixel in the specified pixel format.</DT ><DT ><A HREF="sdlgetrgba.html" >SDL_GetRGBA</A > — Get RGBA values from a pixel in the specified pixel format.</DT ><DT ><A HREF="sdlcreatergbsurface.html" >SDL_CreateRGBSurface</A > — Create an empty SDL_Surface</DT ><DT ><A HREF="sdlcreatergbsurfacefrom.html" >SDL_CreateRGBSurfaceFrom</A > — Create an SDL_Surface from pixel data</DT ><DT ><A HREF="sdlfreesurface.html" >SDL_FreeSurface</A > — Frees (deletes) a SDL_Surface</DT ><DT ><A HREF="sdllocksurface.html" >SDL_LockSurface</A > — Lock a surface for directly access.</DT ><DT ><A HREF="sdlunlocksurface.html" >SDL_UnlockSurface</A > — Unlocks a previously locked surface.</DT ><DT ><A HREF="sdlloadbmp.html" >SDL_LoadBMP</A > — Load a Windows BMP file into an SDL_Surface.</DT ><DT ><A HREF="sdlsavebmp.html" >SDL_SaveBMP</A > — Save an SDL_Surface as a Windows BMP file.</DT ><DT ><A HREF="sdlsetcolorkey.html" >SDL_SetColorKey</A > — Sets the color key (transparent pixel) in a blittable surface and RLE acceleration.</DT ><DT ><A HREF="sdlsetalpha.html" >SDL_SetAlpha</A > — Adjust the alpha properties of a surface</DT ><DT ><A HREF="sdlsetcliprect.html" >SDL_SetClipRect</A > — Sets the clipping rectangle for a surface.</DT ><DT ><A HREF="sdlgetcliprect.html" >SDL_GetClipRect</A > — Gets the clipping rectangle for a surface.</DT ><DT ><A HREF="sdlconvertsurface.html" >SDL_ConvertSurface</A > — Converts a surface to the same format as another surface.</DT ><DT ><A HREF="sdlblitsurface.html" >SDL_BlitSurface</A > — This performs a fast blit from the source surface to the destination surface.</DT ><DT ><A HREF="sdlfillrect.html" >SDL_FillRect</A > — This function performs a fast fill of the given rectangle with some color</DT ><DT ><A HREF="sdldisplayformat.html" >SDL_DisplayFormat</A > — Convert a surface to the display format</DT ><DT ><A HREF="sdldisplayformatalpha.html" >SDL_DisplayFormatAlpha</A > — Convert a surface to the display format</DT ><DT ><A HREF="sdlwarpmouse.html" >SDL_WarpMouse</A > — Set the position of the mouse cursor.</DT ><DT ><A HREF="sdlcreatecursor.html" >SDL_CreateCursor</A > — Creates a new mouse cursor.</DT ><DT ><A HREF="sdlfreecursor.html" >SDL_FreeCursor</A > — Frees a cursor created with SDL_CreateCursor.</DT ><DT ><A HREF="sdlsetcursor.html" >SDL_SetCursor</A > — Set the currently active mouse cursor.</DT ><DT ><A HREF="sdlgetcursor.html" >SDL_GetCursor</A > — Get the currently active mouse cursor.</DT ><DT ><A HREF="sdlshowcursor.html" >SDL_ShowCursor</A > — Toggle whether or not the cursor is shown on the screen.</DT ><DT ><A HREF="sdlglloadlibrary.html" >SDL_GL_LoadLibrary</A > — Specify an OpenGL library</DT ><DT ><A HREF="sdlglgetprocaddress.html" >SDL_GL_GetProcAddress</A > — Get the address of a GL function</DT ><DT ><A HREF="sdlglgetattribute.html" >SDL_GL_GetAttribute</A > — Get the value of a special SDL/OpenGL attribute</DT ><DT ><A HREF="sdlglsetattribute.html" >SDL_GL_SetAttribute</A > — Set a special SDL/OpenGL attribute</DT ><DT ><A HREF="sdlglswapbuffers.html" >SDL_GL_SwapBuffers</A > — Swap OpenGL framebuffers/Update Display</DT ><DT ><A HREF="sdlcreateyuvoverlay.html" >SDL_CreateYUVOverlay</A > — Create a YUV video overlay</DT ><DT ><A HREF="sdllockyuvoverlay.html" >SDL_LockYUVOverlay</A > — Lock an overlay</DT ><DT ><A HREF="sdlunlockyuvoverlay.html" >SDL_UnlockYUVOverlay</A > — Unlock an overlay</DT ><DT ><A HREF="sdldisplayyuvoverlay.html" >SDL_DisplayYUVOverlay</A > — Blit the overlay to the display</DT ><DT ><A HREF="sdlfreeyuvoverlay.html" >SDL_FreeYUVOverlay</A > — Free a YUV video overlay</DT ><DT ><A HREF="sdlglattr.html" >SDL_GLattr</A > — SDL GL Attributes</DT ><DT ><A HREF="sdlrect.html" >SDL_Rect</A > — Defines a rectangular area</DT ><DT ><A HREF="sdlcolor.html" >SDL_Color</A > — Format independent color description</DT ><DT ><A HREF="sdlpalette.html" >SDL_Palette</A > — Color palette for 8-bit pixel formats</DT ><DT ><A HREF="sdlpixelformat.html" >SDL_PixelFormat</A > — Stores surface format information</DT ><DT ><A HREF="sdlsurface.html" >SDL_Surface</A > — Graphical Surface Structure</DT ><DT ><A HREF="sdlvideoinfo.html" >SDL_VideoInfo</A > — Video Target information</DT ><DT ><A HREF="sdloverlay.html" >SDL_Overlay</A > — YUV video overlay</DT ></DL ></DIV ><P >SDL presents a very simple interface to the display framebuffer. The framebuffer is represented as an offscreen surface to which you can write directly. If you want the screen to show what you have written, call the <A HREF="sdlupdaterects.html" >update</A > function which will guarantee that the desired portion of the screen is updated.</P ><P >Before you call any of the SDL video functions, you must first call <SPAN CLASS="TOKEN" >SDL_Init(SDL_INIT_VIDEO)</SPAN >, which initializes the video and events in the SDL library. Check the return code, which should be <SPAN CLASS="RETURNVALUE" >0</SPAN >, to see if there were any errors in starting up.</P ><P >If you use both sound and video in your application, you need to call <SPAN CLASS="TOKEN" >SDL_Init(SDL_INIT_AUDIO | SDL_INIT_VIDEO)</SPAN > before opening the sound device, otherwise under Win32 DirectX, you won't be able to set full-screen display modes.</P ><P >After you have initialized the library, you can start up the video display in a number of ways. The easiest way is to pick a common screen resolution and depth and just initialize the video, checking for errors. You will probably get what you want, but SDL may be emulating your requested mode and converting the display on update. The best way is to <A HREF="sdlgetvideoinfo.html" >query</A >, for the best video mode closest to the desired one, and then <A HREF="sdldisplayformat.html" >convert</A > your images to that pixel format.</P ><P >SDL currently supports any bit depth >= 8 bits per pixel. 8 bpp formats are considered 8-bit palettized modes, while 12, 15, 16, 24, and 32 bits per pixel are considered "packed pixel" modes, meaning each pixel contains the RGB color components packed in the bits of the pixel.</P ><P >After you have initialized your video mode, you can take the surface that was returned, and write to it like any other framebuffer, calling the update routine as you go.</P ><P >When you have finished your video access and are ready to quit your application, you should call "<SPAN CLASS="TOKEN" >SDL_Quit()</SPAN >" to shutdown the video and events.</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdlgeterror.html" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlgetvideosurface.html" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_GetError</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="reference.html" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_GetVideoSurface</TD ></TR ></TABLE ></DIV ></BODY ></HTML >