+++ /dev/null
-/*
- * Copyright (c) 1993-2003, Silicon Graphics, Inc.
- * All Rights Reserved
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose and without fee is hereby granted, provided that the above
- * copyright notice appear in all copies and that both the copyright
- * notice and this permission notice appear in supporting documentation,
- * and that the name of Silicon Graphics, Inc. not be used in
- * advertising or publicity pertaining to distribution of the software
- * without specific, written prior permission.
- *
- * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" AND
- * WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
- * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
- * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
- * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
- * OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION, LOSS OF
- * PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF THIRD
- * PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN ADVISED OF
- * THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE POSSESSION, USE
- * OR PERFORMANCE OF THIS SOFTWARE.
- *
- * US Government Users Restricted Rights
- * Use, duplication, or disclosure by the Government is subject to
- * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
- * (c)(1)(ii) of the Rights in Technical Data and Computer Software
- * clause at DFARS 252.227-7013 and/or in similar or successor clauses
- * in the FAR or the DOD or NASA FAR Supplement. Unpublished - rights
- * reserved under the copyright laws of the United States.
- *
- * Contractor/manufacturer is:
- * Silicon Graphics, Inc.
- * 1500 Crittenden Lane
- * Mountain View, CA 94043
- * United State of America
- *
- * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.
- */
-
-/*
- * histogram.c
- * Compute the histogram of the image. This program illustrates the
- * use of the glHistogram() function.
- */
-
-#include <GL/glew.h>
-#include <GL/glut.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <stdio.h>
-
-#define HISTOGRAM_SIZE 256 /* Must be a power of 2 */
-
-
-static GLubyte *pixels;
-static GLsizei width, height;
-
-
-
-static GLuint bswap(GLuint x)
-{
- const GLuint ui = 1;
- const GLubyte *ubp = (const GLubyte *) &ui;
- if (*ubp == 1) {
- /* we're on little endiang so byteswap x */
- GLsizei y = ((x >> 24)
- | ((x >> 8) & 0xff00)
- | ((x << 8) & 0xff0000)
- | ((x << 24) & 0xff000000));
- return y;
- }
- else {
- return x;
- }
-}
-
-
-static GLubyte*
-readImage( const char* filename, GLsizei* width, GLsizei *height )
-{
- int n;
- GLubyte* pixels;
- size_t num_read;
-
- FILE* infile = fopen( filename, "rb" );
-
- if ( !infile ) {
- fprintf( stderr, "Unable to open file '%s'\n", filename );
- exit(1);
- }
-
- num_read = fread( width, sizeof( GLsizei ), 1, infile );
- assert(num_read == 1);
- num_read = fread( height, sizeof( GLsizei ), 1, infile );
- assert(num_read == 1);
-
- *width = bswap(*width);
- *height = bswap(*height);
-
- n = 3 * (*width) * (*height);
-
- pixels = (GLubyte *) malloc( n * sizeof( GLubyte ));
- if ( !pixels ) {
- fprintf( stderr, "Unable to malloc() bytes for pixels\n" );
- fclose( infile );
- return NULL;
- }
-
- num_read = fread( pixels, sizeof( GLubyte ), n, infile );
- assert(num_read == n);
-
- fclose( infile );
-
- return pixels;
-}
-
-static void init(void)
-{
- if (!glutExtensionSupported("GL_ARB_imaging")) {
- fprintf(stderr, "Sorry, this program requires GL_ARB_imaging.\n");
- exit(1);
- }
-
- glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
- glClearColor(0.0, 0.0, 0.0, 0.0);
-
- glHistogram(GL_HISTOGRAM, HISTOGRAM_SIZE, GL_RGB, GL_FALSE);
- glEnable(GL_HISTOGRAM);
-}
-
-static void display(void)
-{
- int i;
- GLushort values[HISTOGRAM_SIZE][3];
-
- glClear(GL_COLOR_BUFFER_BIT);
- glRasterPos2i(1, 1);
- glDrawPixels(width, height, GL_RGB, GL_UNSIGNED_BYTE, pixels);
-
- glGetHistogram(GL_HISTOGRAM, GL_TRUE, GL_RGB, GL_UNSIGNED_SHORT, values);
-
- /* Plot histogram */
-
- glBegin(GL_LINE_STRIP);
- glColor3f(1.0, 0.0, 0.0);
- for ( i = 0; i < HISTOGRAM_SIZE; i++ )
- glVertex2s(i, values[i][0]);
- glEnd();
-
- glBegin(GL_LINE_STRIP);
- glColor3f(0.0, 1.0, 0.0);
- for ( i = 0; i < HISTOGRAM_SIZE; i++ )
- glVertex2s(i, values[i][1]);
- glEnd();
-
- glBegin(GL_LINE_STRIP);
- glColor3f(0.0, 0.0, 1.0);
- for ( i = 0; i < HISTOGRAM_SIZE; i++ )
- glVertex2s(i, values[i][2]);
- glEnd();
- glFlush();
-}
-
-static void reshape(int w, int h)
-{
- glViewport(0, 0, (GLsizei) w, (GLsizei) h);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glOrtho(0, 256, 0, 10000, -1.0, 1.0);
- glMatrixMode(GL_MODELVIEW);
-}
-
-static void keyboard(unsigned char key, int x, int y)
-{
- static GLboolean sink = GL_FALSE;
-
- switch (key) {
- case 's' :
- sink = !sink;
- glHistogram(GL_HISTOGRAM, HISTOGRAM_SIZE, GL_RGB, sink);
- break;
-
- case 27:
- exit(0);
- }
- glutPostRedisplay();
-
-}
-
-/* Main Loop
- * Open window with initial window size, title bar,
- * RGBA display mode, and handle input events.
- */
-int main(int argc, char** argv)
-{
- pixels = readImage("leeds.bin", &width, &height);
-
- glutInit(&argc, argv);
- glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
- glutInitWindowSize(width, height);
- glutInitWindowPosition(100, 100);
- glutCreateWindow(argv[0]);
- glewInit();
- init();
- glutReshapeFunc(reshape);
- glutKeyboardFunc(keyboard);
- glutDisplayFunc(display);
- glutMainLoop();
- return 0;
-}
projects / mesa.git / blobdiff