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authorBrian Paul <[email protected]>2010-02-15 09:55:01 -0700
committerBrian Paul <[email protected]>2010-02-15 09:55:01 -0700
commitce65a8debe623d72cb4af142ace2be33a2fc575c (patch)
tree3e5bd22dcd76dc56a54bbc8bd759cd6488ef2212 /progs/redbook/convolution.c
parent3be1c11001be872a6850607955e61e82a470c064 (diff)
progs/redbook: add additional tests for GL 1.4
Diffstat (limited to 'progs/redbook/convolution.c')
-rw-r--r--progs/redbook/convolution.c206
1 files changed, 206 insertions, 0 deletions
diff --git a/progs/redbook/convolution.c b/progs/redbook/convolution.c
new file mode 100644
index 00000000000..e120c586327
--- /dev/null
+++ b/progs/redbook/convolution.c
@@ -0,0 +1,206 @@
+/*
+ * 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 Unpublished - rights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.
+ */
+
+/*
+ * convolution.c
+ * Use various 2D convolutions filters to find edges in an image.
+ *
+ */
+#include <GL/glut.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+
+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;
+
+ FILE* infile = fopen( filename, "rb" );
+
+ if ( !infile ) {
+ fprintf( stderr, "Unable to open file '%s'\n", filename );
+ exit(1);
+ }
+
+ fread( width, sizeof( GLsizei ), 1, infile );
+ fread( height, sizeof( GLsizei ), 1, infile );
+
+ *width = bswap(*width);
+ *height = bswap(*height);
+
+ assert(*width > 0);
+ assert(*height > 0);
+
+ n = 3 * (*width) * (*height);
+
+ pixels = (GLubyte *) malloc( n * sizeof( GLubyte ));
+ if ( !pixels ) {
+ fprintf( stderr, "Unable to malloc() bytes for pixels\n" );
+ return NULL;
+ }
+
+ fread( pixels, sizeof( GLubyte ), n, infile );
+
+ fclose( infile );
+
+ return pixels;
+}
+
+
+GLubyte *pixels;
+GLsizei width, height;
+
+GLfloat horizontal[3][3] = {
+ { 0, -1, 0 },
+ { 0, 1, 0 },
+ { 0, 0, 0 }
+};
+
+GLfloat vertical[3][3] = {
+ { 0, 0, 0 },
+ { -1, 1, 0 },
+ { 0, 0, 0 }
+};
+
+GLfloat laplacian[3][3] = {
+ { -0.125, -0.125, -0.125 },
+ { -0.125, 1.0 , -0.125 },
+ { -0.125, -0.125, -0.125 },
+};
+
+
+static void init(void)
+{
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ glClearColor(0.0, 0.0, 0.0, 0.0);
+
+ printf("Using the horizontal filter\n");
+ glConvolutionFilter2D(GL_CONVOLUTION_2D, GL_LUMINANCE,
+ 3, 3, GL_LUMINANCE, GL_FLOAT, horizontal);
+ glEnable(GL_CONVOLUTION_2D);
+}
+
+static void display(void)
+{
+ glClear(GL_COLOR_BUFFER_BIT);
+ glRasterPos2i( 1, 1);
+ glDrawPixels(width, height, GL_RGB, GL_UNSIGNED_BYTE, pixels);
+ glFlush();
+}
+
+static void reshape(int w, int h)
+{
+ glViewport(0, 0, (GLsizei) w, (GLsizei) h);
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(0, w, 0, h, -1.0, 1.0);
+ glMatrixMode(GL_MODELVIEW);
+}
+
+static void keyboard(unsigned char key, int x, int y)
+{
+ switch (key) {
+ case 'h' :
+ printf("Using a horizontal filter\n");
+ glConvolutionFilter2D(GL_CONVOLUTION_2D, GL_LUMINANCE, 3, 3,
+ GL_LUMINANCE, GL_FLOAT, horizontal);
+ break;
+
+ case 'v' :
+ printf("Using the vertical filter\n");
+ glConvolutionFilter2D(GL_CONVOLUTION_2D, GL_LUMINANCE, 3, 3,
+ GL_LUMINANCE, GL_FLOAT, vertical);
+ break;
+
+ case 'l' :
+ printf("Using the laplacian filter\n");
+ glConvolutionFilter2D(GL_CONVOLUTION_2D, GL_LUMINANCE, 3, 3,
+ GL_LUMINANCE, GL_FLOAT, laplacian);
+ 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_RGBA);
+ glutInitWindowSize(width, height);
+ glutInitWindowPosition(100, 100);
+ glutCreateWindow(argv[0]);
+ init();
+ glutReshapeFunc(reshape);
+ glutKeyboardFunc(keyboard);
+ glutDisplayFunc(display);
+ glutMainLoop();
+ return 0;
+}