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diff --git a/distrib/sdl-1.2.15/docs/html/guidevideo.html b/distrib/sdl-1.2.15/docs/html/guidevideo.html new file mode 100644 index 0000000..85da77d --- /dev/null +++ b/distrib/sdl-1.2.15/docs/html/guidevideo.html @@ -0,0 +1,463 @@ +<HTML +><HEAD +><TITLE +>Graphics and Video</TITLE +><META +NAME="GENERATOR" +CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ +"><LINK +REL="HOME" +TITLE="SDL Library Documentation" +HREF="index.html"><LINK +REL="UP" +TITLE="SDL Guide" +HREF="guide.html"><LINK +REL="PREVIOUS" +TITLE="Initializing SDL" +HREF="guidebasicsinit.html"><LINK +REL="NEXT" +TITLE="Using OpenGL With SDL" +HREF="guidevideoopengl.html"></HEAD +><BODY +CLASS="CHAPTER" +BGCOLOR="#FFF8DC" +TEXT="#000000" +LINK="#0000ee" +VLINK="#551a8b" +ALINK="#ff0000" +><DIV +CLASS="NAVHEADER" +><TABLE +SUMMARY="Header navigation 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="guidebasicsinit.html" +ACCESSKEY="P" +>Prev</A +></TD +><TD +WIDTH="80%" +ALIGN="center" +VALIGN="bottom" +></TD +><TD +WIDTH="10%" +ALIGN="right" +VALIGN="bottom" +><A +HREF="guidevideoopengl.html" +ACCESSKEY="N" +>Next</A +></TD +></TR +></TABLE +><HR +ALIGN="LEFT" +WIDTH="100%"></DIV +><DIV +CLASS="CHAPTER" +><H1 +><A +NAME="GUIDEVIDEO" +></A +>Chapter 2. Graphics and Video</H1 +><DIV +CLASS="TOC" +><DL +><DT +><B +>Table of Contents</B +></DT +><DT +><A +HREF="guidevideo.html#GUIDEVIDEOINTRO" +>Introduction to SDL Video</A +></DT +><DT +><A +HREF="guidevideoopengl.html" +>Using OpenGL With SDL</A +></DT +></DL +></DIV +><DIV +CLASS="SECT1" +><H1 +CLASS="SECT1" +><A +NAME="GUIDEVIDEOINTRO" +></A +>Introduction to SDL Video</H1 +><P +>Video is probably the most common thing that SDL is used for, and +so it has the most complete subsystem. Here are a few +examples to demonstrate the basics.</P +><DIV +CLASS="SECT2" +><H2 +CLASS="SECT2" +><A +NAME="AEN68" +></A +>Initializing the Video Display</H2 +><P +>This is what almost all SDL programs have to do in one way or +another.</P +><DIV +CLASS="EXAMPLE" +><A +NAME="AEN71" +></A +><P +><B +>Example 2-1. Initializing the Video Display</B +></P +><PRE +CLASS="PROGRAMLISTING" +> SDL_Surface *screen; + + /* Initialize the SDL library */ + if( SDL_Init(SDL_INIT_VIDEO) < 0 ) { + fprintf(stderr, + "Couldn't initialize SDL: %s\n", SDL_GetError()); + exit(1); + } + + /* Clean up on exit */ + atexit(SDL_Quit); + + /* + * Initialize the display in a 640x480 8-bit palettized mode, + * requesting a software surface + */ + screen = SDL_SetVideoMode(640, 480, 8, SDL_SWSURFACE); + if ( screen == NULL ) { + fprintf(stderr, "Couldn't set 640x480x8 video mode: %s\n", + SDL_GetError()); + exit(1); + }</PRE +></DIV +></DIV +><DIV +CLASS="SECT2" +><H2 +CLASS="SECT2" +><A +NAME="AEN74" +></A +>Initializing the Best Video Mode</H2 +><P +>If you have a preference for a certain pixel depth but will accept any +other, use SDL_SetVideoMode with SDL_ANYFORMAT as below. You can also +use SDL_VideoModeOK() to find the native video mode that is closest to +the mode you request.</P +><DIV +CLASS="EXAMPLE" +><A +NAME="AEN77" +></A +><P +><B +>Example 2-2. Initializing the Best Video Mode</B +></P +><PRE +CLASS="PROGRAMLISTING" +> /* Have a preference for 8-bit, but accept any depth */ + screen = SDL_SetVideoMode(640, 480, 8, SDL_SWSURFACE|SDL_ANYFORMAT); + if ( screen == NULL ) { + fprintf(stderr, "Couldn't set 640x480x8 video mode: %s\n", + SDL_GetError()); + exit(1); + } + printf("Set 640x480 at %d bits-per-pixel mode\n", + screen->format->BitsPerPixel);</PRE +></DIV +></DIV +><DIV +CLASS="SECT2" +><H2 +CLASS="SECT2" +><A +NAME="AEN80" +></A +>Loading and Displaying a BMP File</H2 +><P +>The following function loads and displays a BMP file given as +argument, once SDL is initialised and a video mode has been set.</P +><DIV +CLASS="EXAMPLE" +><A +NAME="AEN83" +></A +><P +><B +>Example 2-3. Loading and Displaying a BMP File</B +></P +><PRE +CLASS="PROGRAMLISTING" +>void display_bmp(char *file_name) +{ + SDL_Surface *image; + + /* Load the BMP file into a surface */ + image = SDL_LoadBMP(file_name); + if (image == NULL) { + fprintf(stderr, "Couldn't load %s: %s\n", file_name, SDL_GetError()); + return; + } + + /* + * Palettized screen modes will have a default palette (a standard + * 8*8*4 colour cube), but if the image is palettized as well we can + * use that palette for a nicer colour matching + */ + if (image->format->palette && screen->format->palette) { + SDL_SetColors(screen, image->format->palette->colors, 0, + image->format->palette->ncolors); + } + + /* Blit onto the screen surface */ + if(SDL_BlitSurface(image, NULL, screen, NULL) < 0) + fprintf(stderr, "BlitSurface error: %s\n", SDL_GetError()); + + SDL_UpdateRect(screen, 0, 0, image->w, image->h); + + /* Free the allocated BMP surface */ + SDL_FreeSurface(image); +}</PRE +></DIV +></DIV +><DIV +CLASS="SECT2" +><H2 +CLASS="SECT2" +><A +NAME="AEN86" +></A +>Drawing Directly to the Display</H2 +><P +>The following two functions can be used to get and set single +pixels of a surface. They are carefully written to work with any depth +currently supported by SDL. Remember to lock the surface before +calling them, and to unlock it before calling any other SDL +functions.</P +><P +>To convert between pixel values and their red, green, blue +components, use SDL_GetRGB() and SDL_MapRGB().</P +><DIV +CLASS="EXAMPLE" +><A +NAME="AEN90" +></A +><P +><B +>Example 2-4. getpixel()</B +></P +><PRE +CLASS="PROGRAMLISTING" +>/* + * Return the pixel value at (x, y) + * NOTE: The surface must be locked before calling this! + */ +Uint32 getpixel(SDL_Surface *surface, int x, int y) +{ + int bpp = surface->format->BytesPerPixel; + /* Here p is the address to the pixel we want to retrieve */ + Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp; + + switch(bpp) { + case 1: + return *p; + + case 2: + return *(Uint16 *)p; + + case 3: + if(SDL_BYTEORDER == SDL_BIG_ENDIAN) + return p[0] << 16 | p[1] << 8 | p[2]; + else + return p[0] | p[1] << 8 | p[2] << 16; + + case 4: + return *(Uint32 *)p; + + default: + return 0; /* shouldn't happen, but avoids warnings */ + } +}</PRE +></DIV +><DIV +CLASS="EXAMPLE" +><A +NAME="AEN93" +></A +><P +><B +>Example 2-5. putpixel()</B +></P +><PRE +CLASS="PROGRAMLISTING" +>/* + * Set the pixel at (x, y) to the given value + * NOTE: The surface must be locked before calling this! + */ +void putpixel(SDL_Surface *surface, int x, int y, Uint32 pixel) +{ + int bpp = surface->format->BytesPerPixel; + /* Here p is the address to the pixel we want to set */ + Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp; + + switch(bpp) { + case 1: + *p = pixel; + break; + + case 2: + *(Uint16 *)p = pixel; + break; + + case 3: + if(SDL_BYTEORDER == SDL_BIG_ENDIAN) { + p[0] = (pixel >> 16) & 0xff; + p[1] = (pixel >> 8) & 0xff; + p[2] = pixel & 0xff; + } else { + p[0] = pixel & 0xff; + p[1] = (pixel >> 8) & 0xff; + p[2] = (pixel >> 16) & 0xff; + } + break; + + case 4: + *(Uint32 *)p = pixel; + break; + } +}</PRE +></DIV +><P +>The following code uses the putpixel() function above to set a +yellow pixel in the middle of the screen.</P +><DIV +CLASS="EXAMPLE" +><A +NAME="AEN97" +></A +><P +><B +>Example 2-6. Using putpixel()</B +></P +><PRE +CLASS="PROGRAMLISTING" +> /* Code to set a yellow pixel at the center of the screen */ + + int x, y; + Uint32 yellow; + + /* Map the color yellow to this display (R=0xff, G=0xFF, B=0x00) + Note: If the display is palettized, you must set the palette first. + */ + yellow = SDL_MapRGB(screen->format, 0xff, 0xff, 0x00); + + x = screen->w / 2; + y = screen->h / 2; + + /* Lock the screen for direct access to the pixels */ + if ( SDL_MUSTLOCK(screen) ) { + if ( SDL_LockSurface(screen) < 0 ) { + fprintf(stderr, "Can't lock screen: %s\n", SDL_GetError()); + return; + } + } + + putpixel(screen, x, y, yellow); + + if ( SDL_MUSTLOCK(screen) ) { + SDL_UnlockSurface(screen); + } + /* Update just the part of the display that we've changed */ + SDL_UpdateRect(screen, x, y, 1, 1); + + return; </PRE +></DIV +></DIV +></DIV +></DIV +><DIV +CLASS="NAVFOOTER" +><HR +ALIGN="LEFT" +WIDTH="100%"><TABLE +SUMMARY="Footer navigation table" +WIDTH="100%" +BORDER="0" +CELLPADDING="0" +CELLSPACING="0" +><TR +><TD +WIDTH="33%" +ALIGN="left" +VALIGN="top" +><A +HREF="guidebasicsinit.html" +ACCESSKEY="P" +>Prev</A +></TD +><TD +WIDTH="34%" +ALIGN="center" +VALIGN="top" +><A +HREF="index.html" +ACCESSKEY="H" +>Home</A +></TD +><TD +WIDTH="33%" +ALIGN="right" +VALIGN="top" +><A +HREF="guidevideoopengl.html" +ACCESSKEY="N" +>Next</A +></TD +></TR +><TR +><TD +WIDTH="33%" +ALIGN="left" +VALIGN="top" +>Initializing SDL</TD +><TD +WIDTH="34%" +ALIGN="center" +VALIGN="top" +><A +HREF="guide.html" +ACCESSKEY="U" +>Up</A +></TD +><TD +WIDTH="33%" +ALIGN="right" +VALIGN="top" +>Using OpenGL With SDL</TD +></TR +></TABLE +></DIV +></BODY +></HTML +>
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