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/*
* setgetscreenres.m
*
* juanfc 2009-04-13
* jawsoftware 2009-04-17
* Based on newscreen
* Created by Jeffrey Osterman on 10/30/07.
* Copyright 2007 Jeffrey Osterman. All rights reserved.
* PROVIDED AS IS AND WITH NO WARRANTIES WHATSOEVER
* http://forums.macosxhints.com/showthread.php?t=59575
*
* COMPILE:
* c++ setgetscreenres.m -framework ApplicationServices -o setgetscreenres
* USE:
* setgetscreenres [ -l | 1..9] [ 1440 900 ]
*/
#include <ApplicationServices/ApplicationServices.h>
bool MyDisplaySwitchToMode (CGDirectDisplayID display, CFDictionaryRef mode);
void ListDisplays( CGDisplayCount dispCount, CGDirectDisplayID *dispArray );
void usage(const char *argv[]);
void GetDisplayParms(CGDirectDisplayID *dispArray, CGDisplayCount dispNum, int *width, int *height, int *depth, int *freq);
int main (int argc, const char * argv[])
{
int h; // horizontal resolution
int v; // vertical resolution
int depth, freq;
CFDictionaryRef switchMode; // mode to switch to
CGDirectDisplayID theDisplay; // ID of display, display to set
int displayNum; //display number requested by user
CGDisplayCount maxDisplays = 10;
CGDirectDisplayID onlineDspys[maxDisplays];
CGDisplayCount dspyCnt;
CGGetOnlineDisplayList (maxDisplays, onlineDspys, &dspyCnt);
if (argc == 1) {
CGRect screenFrame = CGDisplayBounds(kCGDirectMainDisplay);
CGSize screenSize = screenFrame.size;
printf("%.0f %.0f\n", screenSize.width, screenSize.height);
return 0;
}
if (argc == 2) {
if (! strcmp(argv[1],"-l")) {
ListDisplays( dspyCnt, onlineDspys );
return 0;
}
else if (! strcmp(argv[1],"-?")) {
usage(argv);
return 0;
}
else if (displayNum = atoi(argv[1])) {
if (displayNum <= dspyCnt) {
GetDisplayParms(onlineDspys, displayNum-1, &h, &v, &depth, &freq);
printf("%d %d\n", h, v);
return 0;
}
else {
fprintf(stderr, "ERROR: display number out of bounds; displays on this mac: %d.\n", dspyCnt);
return -1;
}
}
}
if (argc == 4 && (displayNum = atoi(argv[1])) && (h = atoi(argv[2])) && (v = atoi(argv[3])) ) {
if (displayNum <= dspyCnt) {
theDisplay= onlineDspys[displayNum-1];
}
else return -1;
}
else {
if (argc != 3 || !(h = atoi(argv[1])) || !(v = atoi(argv[2])) ) {
fprintf(stderr, "ERROR: syntax error.\n", argv[0]);
usage(argv);
return -1;
}
theDisplay = CGMainDisplayID();
}
switchMode = CGDisplayBestModeForParameters(theDisplay, 32, h, v, NULL);
if (! MyDisplaySwitchToMode(theDisplay, switchMode)) {
fprintf(stderr, "Error changing resolution to %d %d\n", h, v);
return 1;
}
return 0;
}
void ListDisplays( CGDisplayCount dispCount, CGDirectDisplayID *dispArray )
{
int h, v, depth, freq, i;
CGDirectDisplayID mainDisplay = CGMainDisplayID();
printf("Displays found: %d\n", dispCount);
for (i = 0 ; i < dispCount ; i++ ) {
GetDisplayParms(dispArray, i, &h, &v, &depth, &freq);
printf("Display %d (id %d): %d x %d x %d @ %dHz", i+1, dispArray[i], h, v, depth, freq);
if ( mainDisplay == dispArray[i] )
printf(" (main)\n");
else
printf("\n");
}
}
void GetDisplayParms(CGDirectDisplayID *dispArray, CGDisplayCount dispNum, int *width, int *height, int *depth, int *freq)
{
CFDictionaryRef currentMode = CGDisplayCurrentMode (dispArray[dispNum]);
CFNumberRef number = CFDictionaryGetValue (currentMode, kCGDisplayRefreshRate);
CFNumberGetValue (number, kCFNumberLongType, freq);
number = CFDictionaryGetValue (currentMode, kCGDisplayWidth);
CFNumberGetValue (number, kCFNumberLongType, width);
number = CFDictionaryGetValue (currentMode, kCGDisplayHeight);
CFNumberGetValue (number, kCFNumberLongType, height);
number = CFDictionaryGetValue (currentMode, kCGDisplayBitsPerPixel);
CFNumberGetValue (number, kCFNumberLongType, depth);
}
bool MyDisplaySwitchToMode (CGDirectDisplayID display, CFDictionaryRef mode)
{
CGDisplayConfigRef config;
if (CGBeginDisplayConfiguration(&config) == kCGErrorSuccess) {
CGConfigureDisplayMode(config, display, mode);
CGCompleteDisplayConfiguration(config, kCGConfigureForSession );
return true;
}
return false;
}
void usage(const char *argv[])
{
printf("\nUsage: %s [-l | 1..9 ] [ hor_res vert_res]\n\n", argv[0]);
printf(" -l list resolution, depth and refresh rate of all displays\n");
printf(" 1..9 display # (default: main display)\n");
printf(" hor_res horizontal resolution\n");
printf("vert_res vertical resolution\n\n");
printf("Examples:\n");
printf("%s 800 600 set resolution of main display to 800x600\n", argv[0]);
printf("%s 2 800 600 set resolution of secondary display to 800x600\n", argv[0]);
printf("%s 3 get resolution of third display\n", argv[0]);
printf("%s -l get resolution, bit depth and refresh rate of all displays\n\n", argv[0]);
}
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