c:graphics.h:setgraphbufsize
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| + | ===== setgraphbufsize ===== | ||
| + | |||
| + | |||
| + | ====Syntax of setgraphbufsize ==== | ||
| + | <code c> | ||
| + | #include <graphics.h> | ||
| + | unsigned setgraphbufsize(unsigned bufsize); | ||
| + | </code> | ||
| + | |||
| + | |||
| + | ==== Description of setgraphbufsize ==== | ||
| + | <code c> | ||
| + | Some of the graphics routines (such as floodfill) use a memory buffer | ||
| + | that is allocated when initgraph is called and released when closegraph | ||
| + | is called. The default size of this buffer, allocated by _graphgetmem, is | ||
| + | 4,096 bytes. | ||
| + | You might want to make this buffer smaller (to save memory space) or | ||
| + | bigger (if, for example, a call to floodfill produces error -7: Out of | ||
| + | flood memory). | ||
| + | setgraphbufsize tells initgraph how much memory to allocate for this | ||
| + | internal graphics buffer when it calls _graphgetmem. | ||
| + | You must call setgraphbufsize before calling initgraph. Once initgraph | ||
| + | has been called, all calls to setgraphbufsize are ignored until after the | ||
| + | next call to closegraph. | ||
| + | </code> | ||
| + | |||
| + | |||
| + | ==== Example of setgraphbufsize ==== | ||
| + | <code c> | ||
| + | /* setgraphbufsize example */ | ||
| + | |||
| + | #include <graphics.h> | ||
| + | #include <stdlib.h> | ||
| + | #include <stdio.h> | ||
| + | #include <conio.h> | ||
| + | |||
| + | #define BUFSIZE 1000 /* internal graphics buffer size */ | ||
| + | |||
| + | int main(void) | ||
| + | { | ||
| + | /* request autodetection */ | ||
| + | int gdriver = DETECT, gmode, errorcode; | ||
| + | int x, y, oldsize; | ||
| + | char msg[80]; | ||
| + | |||
| + | /* _set size of internal graphics buffer before calling initgraph */ | ||
| + | oldsize = setgraphbufsize(BUFSIZE); | ||
| + | |||
| + | |||
| + | /* initialize graphics and local variables */ | ||
| + | initgraph(&gdriver, &gmode, ""); | ||
| + | |||
| + | |||
| + | /* read result of initialization */ | ||
| + | errorcode = graphresult(); | ||
| + | if (errorcode != grOk) { /* an error occurred */ | ||
| + | printf("Graphics error: %s\n", grapherrormsg(errorcode)); | ||
| + | printf("Press any key to halt:"); | ||
| + | getch(); | ||
| + | exit(1); /* terminate with an error code */ | ||
| + | } | ||
| + | |||
| + | x = getmaxx() / 2; | ||
| + | y = getmaxy() / 2; | ||
| + | |||
| + | /* output some messages */ | ||
| + | sprintf(msg, "Graphics buffer size: %d", BUFSIZE); | ||
| + | settextjustify(CENTER_TEXT, CENTER_TEXT); | ||
| + | |||
| + | outtextxy(x, y, msg); | ||
| + | sprintf(msg, "Old graphics buffer size: %d", oldsize); | ||
| + | outtextxy(x, y+textheight("W"), msg); | ||
| + | |||
| + | /* clean up */ | ||
| + | getch(); | ||
| + | closegraph(); | ||
| + | return 0; | ||
| + | } | ||
| + | </code> | ||
| + | |||
| + | |||
| + | ==== See also ==== | ||
| + | [[closegraph]] | ||
| + | [[initgraph]] | ||
| + | [[sector]] | ||
| + | |||
| + | |||
| + | ===== output of setgraphbufsize example ===== | ||
| + | |||
| + | no output of example at the moment | ||
| + | do not hesitate and add it... | ||
| + | |||
| + | |||
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c/graphics.h/setgraphbufsize.txt · Last modified: 2024/02/16 01:05 (external edit)
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