+++ /dev/null
-/**
- * Dissolve between two images using randomized/patterned stencil buffer
- * and varying stencil ref.
- *
- * Brian Paul
- * 29 Jan 2010
- */
-
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include <GL/glut.h>
-#include "readtex.h"
-
-#define FILE1 "../images/bw.rgb"
-#define FILE2 "../images/arch.rgb"
-
-
-static int Win;
-static int WinWidth = 400, WinHeight = 400;
-static GLboolean Anim = GL_TRUE;
-
-static int ImgWidth[2], ImgHeight[2];
-static GLenum ImgFormat[2];
-static GLubyte *Image[2];
-static GLfloat ScaleX[2], ScaleY[2];
-
-static GLubyte StencilRef = 0;
-
-static int Mode = 0;
-
-
-static void
-Idle(void)
-{
- StencilRef = (GLint) (glutGet(GLUT_ELAPSED_TIME) / 10);
- glutPostRedisplay();
-}
-
-
-static void
-FillRandomPixels(GLubyte *b)
-{
- int i;
- for (i = 0; i < WinWidth * WinHeight; i++) {
- b[i] = rand() & 0xff;
- }
-}
-
-
-static void
-FillRandomRects(GLubyte *b)
-{
- int i;
-
- memset(b, 0, WinWidth * WinHeight);
-
- for (i = 0; i < 256; i++) {
- int x = rand() % WinWidth;
- int y = rand() % WinHeight;
- int w = rand() % 60;
- int h = rand() % 60;
- int ix, iy;
-
- if (x + w > WinWidth)
- w = WinWidth - x;
- if (y + h > WinHeight)
- h = WinHeight - y;
-
- for (iy = 0; iy < h; iy++) {
- for (ix = 0; ix < w; ix++) {
- int p = (y + iy) * WinWidth + x + ix;
- b[p] = i;
- }
- }
- }
-}
-
-
-static void
-FillWipe(GLubyte *b)
-{
- int iy, ix;
-
- memset(b, 0, WinWidth * WinHeight);
-
- for (iy = 0; iy < WinHeight; iy++) {
- for (ix = 0; ix < WinWidth; ix++) {
- int p = iy * WinWidth + ix;
- b[p] = 2 * ix + iy / 2;
- }
- }
-}
-
-
-static void
-FillMoire(GLubyte *b)
-{
- int iy, ix;
-
- memset(b, 0, WinWidth * WinHeight);
-
- for (iy = 0; iy < WinHeight; iy++) {
- for (ix = 0; ix < WinWidth; ix++) {
- int p = iy * WinWidth + ix;
- b[p] = (ix / 2) * (ix / 2) - (iy / 2) * (iy / 2);
- }
- }
-}
-
-
-static void
-FillWaves(GLubyte *b)
-{
- int iy, ix;
-
- memset(b, 0, WinWidth * WinHeight);
-
- for (iy = 0; iy < WinHeight; iy++) {
- for (ix = 0; ix < WinWidth; ix++) {
- int p = iy * WinWidth + ix;
- float x = 8.0 * 3.1415 * ix / (float) WinWidth;
- b[p] = (int) (25.0 * sin(x) ) - iy*2;
- }
- }
-}
-
-
-typedef void (*FillFunc)(GLubyte *b);
-
-
-static FillFunc Funcs[] = {
- FillRandomPixels,
- FillRandomRects,
- FillWipe,
- FillMoire,
- FillWaves
-};
-
-#define NUM_MODES (sizeof(Funcs) / sizeof(Funcs[0]))
-
-
-
-static void
-InitStencilBuffer(void)
-{
- GLubyte *b = malloc(WinWidth * WinHeight);
-
- Funcs[Mode](b);
-
- glStencilFunc(GL_ALWAYS, 0, ~0);
- glPixelZoom(1.0, 1.0);
- glDrawPixels(WinWidth, WinHeight, GL_STENCIL_INDEX, GL_UNSIGNED_BYTE, b);
-
- free(b);
-}
-
-
-static void
-Draw(void)
-{
- glClear(GL_COLOR_BUFFER_BIT);
-
- glPixelZoom(ScaleX[0], ScaleY[0]);
- glStencilFunc(GL_LESS, StencilRef, ~0);
- glDrawPixels(ImgWidth[0], ImgHeight[0], ImgFormat[0], GL_UNSIGNED_BYTE, Image[0]);
-
- glPixelZoom(ScaleX[1], ScaleY[1]);
- glStencilFunc(GL_GEQUAL, StencilRef, ~0);
- glDrawPixels(ImgWidth[1], ImgHeight[1], ImgFormat[1], GL_UNSIGNED_BYTE, Image[1]);
-
- glutSwapBuffers();
-}
-
-
-static void
-Reshape(int width, int height)
-{
- WinWidth = width;
- WinHeight = height;
- glViewport(0, 0, width, height);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glFrustum(-1.0, 1.0, -1.0, 1.0, 5.0, 25.0);
- glMatrixMode(GL_MODELVIEW);
- glLoadIdentity();
- glTranslatef(0.0, 0.0, -15.0);
-
- InitStencilBuffer();
-
- ScaleX[0] = (float) width / ImgWidth[0];
- ScaleY[0] = (float) height / ImgHeight[0];
-
- ScaleX[1] = (float) width / ImgWidth[1];
- ScaleY[1] = (float) height / ImgHeight[1];
-}
-
-
-static void
-Key(unsigned char key, int x, int y)
-{
- (void) x;
- (void) y;
- switch (key) {
- case 'a':
- case ' ':
- Anim = !Anim;
- if (Anim)
- glutIdleFunc(Idle);
- else
- glutIdleFunc(NULL);
- break;
- case 'i':
- InitStencilBuffer();
- break;
- case '-':
- StencilRef--;
- break;
- case '+':
- StencilRef++;
- break;
- case 'm':
- Mode = (Mode + 1) % NUM_MODES;
- InitStencilBuffer();
- break;
- case 27:
- glutDestroyWindow(Win);
- exit(0);
- break;
- }
- glutPostRedisplay();
-}
-
-
-
-static void
-Init(void)
-{
- Image[0] = LoadRGBImage(FILE1, &ImgWidth[0], &ImgHeight[0], &ImgFormat[0]);
- if (!Image[0]) {
- printf("Couldn't read %s\n", FILE1);
- exit(0);
- }
-
- Image[1] = LoadRGBImage(FILE2, &ImgWidth[1], &ImgHeight[1], &ImgFormat[1]);
- if (!Image[1]) {
- printf("Couldn't read %s\n", FILE2);
- exit(0);
- }
-
- glEnable(GL_STENCIL_TEST);
- glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
-
- glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-}
-
-
-int
-main(int argc, char *argv[])
-{
- glutInitWindowSize(WinWidth, WinHeight);
- glutInit(&argc, argv);
- glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL);
- Win = glutCreateWindow(argv[0]);
- glutReshapeFunc(Reshape);
- glutKeyboardFunc(Key);
- glutDisplayFunc(Draw);
- if (Anim)
- glutIdleFunc(Idle);
- Init();
-
- printf("Keys:\n");
- printf(" a/SPACE toggle animation\n");
- printf(" +/- single step\n");
- printf(" i re-init pattern\n");
- printf(" m change pattern/dissolve mode\n");
- printf(" ESC exit\n");
-
- glutMainLoop();
- return 0;
-}
projects / mesa.git / blobdiff