diff options
Diffstat (limited to 'nx-X11/extras/Mesa_6.4.2/progs/demos/shadowtex.c')
| -rw-r--r-- | nx-X11/extras/Mesa_6.4.2/progs/demos/shadowtex.c | 600 |
1 files changed, 600 insertions, 0 deletions
diff --git a/nx-X11/extras/Mesa_6.4.2/progs/demos/shadowtex.c b/nx-X11/extras/Mesa_6.4.2/progs/demos/shadowtex.c new file mode 100644 index 000000000..e918751a7 --- /dev/null +++ b/nx-X11/extras/Mesa_6.4.2/progs/demos/shadowtex.c @@ -0,0 +1,600 @@ +/* + * Shadow demo using the GL_ARB_depth_texture, GL_ARB_shadow and + * GL_ARB_shadow_ambient extensions (or the old SGIX extensions). + * + * Brian Paul + * 19 Feb 2001 + * + * Added GL_EXT_shadow_funcs support on 23 March 2002 + * + * Copyright (C) 1999-2001 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <math.h> +#include <GL/glut.h> +#include "showbuffer.h" + +#if 0 /* change to 1 if you want to use the old SGIX extensions */ +#undef GL_ARB_depth_texture +#undef GL_ARB_shadow +#undef GL_ARB_shadow_ambient +#endif + + +#define DEG_TO_RAD (3.14159 / 180.0) + +static GLint WindowWidth = 450, WindowHeight = 300; +static GLfloat Xrot = 15, Yrot = 0, Zrot = 0; + +static GLfloat Red[4] = {1, 0, 0, 1}; +static GLfloat Green[4] = {0, 1, 0, 1}; +static GLfloat Blue[4] = {0, 0, 1, 1}; +static GLfloat Yellow[4] = {1, 1, 0, 1}; + +static GLfloat LightDist = 10; +static GLfloat LightLatitude = 45.0; +static GLfloat LightLongitude = 45.0; +static GLfloat LightPos[4]; +static GLfloat SpotDir[3]; +static GLfloat SpotAngle = 40.0 * DEG_TO_RAD; +static GLfloat ShadowNear = 4.0, ShadowFar = 24.0; +static GLint ShadowTexWidth = 256, ShadowTexHeight = 256; + +static GLboolean LinearFilter = GL_FALSE; + +static GLfloat Bias = -0.06; + +static GLboolean Anim = GL_TRUE; + +static GLboolean HaveEXTshadowFuncs = GL_FALSE; +static GLint Operator = 0; +static const GLenum OperatorFunc[8] = { + GL_LEQUAL, GL_LESS, GL_GEQUAL, GL_GREATER, + GL_EQUAL, GL_NOTEQUAL, GL_ALWAYS, GL_NEVER }; +static const char *OperatorName[8] = { + "GL_LEQUAL", "GL_LESS", "GL_GEQUAL", "GL_GREATER", + "GL_EQUAL", "GL_NOTEQUAL", "GL_ALWAYS", "GL_NEVER" }; + + +static GLuint DisplayMode; +#define SHOW_NORMAL 0 +#define SHOW_DEPTH_IMAGE 1 +#define SHOW_DEPTH_MAPPING 2 +#define SHOW_DISTANCE 3 + + + +static void +DrawScene(void) +{ + GLfloat k = 6; + /* sphere */ + glPushMatrix(); + glTranslatef(1.6, 2.2, 2.7); + glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, Green); + glColor4fv(Green); + glutSolidSphere(1.5, 15, 15); + glPopMatrix(); + /* dodecahedron */ + glPushMatrix(); + glTranslatef(-2.0, 1.2, 2.1); + glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, Red); + glColor4fv(Red); + glutSolidDodecahedron(); + glPopMatrix(); + /* icosahedron */ + glPushMatrix(); + glTranslatef(-0.6, 1.3, -0.5); + glScalef(1.5, 1.5, 1.5); + glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, Yellow); + glColor4fv(Red); + glutSolidIcosahedron(); + glPopMatrix(); + /* a plane */ + glPushMatrix(); + glTranslatef(0, -1.1, 0); + glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, Blue); + glColor4fv(Blue); + glNormal3f(0, 1, 0); + glBegin(GL_POLYGON); + glVertex3f(-k, 0, -k); + glVertex3f( k, 0, -k); + glVertex3f( k, 0, k); + glVertex3f(-k, 0, k); + glEnd(); + glPopMatrix(); +} + + +/* + * Load the GL_TEXTURE matrix with the projection from the light + * source's point of view. + */ +static void +MakeShadowMatrix(const GLfloat lightPos[4], const GLfloat spotDir[3], + GLfloat spotAngle, GLfloat shadowNear, GLfloat shadowFar) +{ + GLfloat d; + + glMatrixMode(GL_TEXTURE); + glLoadIdentity(); + glTranslatef(0.5, 0.5, 0.5 + Bias); + glScalef(0.5, 0.5, 0.5); + d = shadowNear * tan(spotAngle); + glFrustum(-d, d, -d, d, shadowNear, shadowFar); + gluLookAt(lightPos[0], lightPos[1], lightPos[2], + lightPos[0] + spotDir[0], + lightPos[1] + spotDir[1], + lightPos[2] + spotDir[2], + 0, 1, 0); + glMatrixMode(GL_MODELVIEW); +} + + +static void +EnableIdentityTexgen(void) +{ + /* texgen so that texcoord = vertex coord */ + static GLfloat sPlane[4] = { 1, 0, 0, 0 }; + static GLfloat tPlane[4] = { 0, 1, 0, 0 }; + static GLfloat rPlane[4] = { 0, 0, 1, 0 }; + static GLfloat qPlane[4] = { 0, 0, 0, 1 }; + + glTexGenfv(GL_S, GL_EYE_PLANE, sPlane); + glTexGenfv(GL_T, GL_EYE_PLANE, tPlane); + glTexGenfv(GL_R, GL_EYE_PLANE, rPlane); + glTexGenfv(GL_Q, GL_EYE_PLANE, qPlane); + glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); + glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); + glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); + glTexGeni(GL_Q, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); + + glEnable(GL_TEXTURE_GEN_S); + glEnable(GL_TEXTURE_GEN_T); + glEnable(GL_TEXTURE_GEN_R); + glEnable(GL_TEXTURE_GEN_Q); +} + + +/* + * Setup 1-D texgen so that the distance from the light source, between + * the near and far planes maps to s=0 and s=1. When we draw the scene, + * the grayness will indicate the fragment's distance from the light + * source. + */ +static void +EnableDistanceTexgen(const GLfloat lightPos[4], const GLfloat lightDir[3], + GLfloat lightNear, GLfloat lightFar) +{ + GLfloat m, d; + GLfloat sPlane[4]; + GLfloat nearPoint[3]; + + m = sqrt(lightDir[0] * lightDir[0] + + lightDir[1] * lightDir[1] + + lightDir[2] * lightDir[2]); + + d = lightFar - lightNear; + + /* nearPoint = point on light direction vector which intersects the + * near plane of the light frustum. + */ + nearPoint[0] = LightPos[0] + lightDir[0] / m * lightNear; + nearPoint[1] = LightPos[1] + lightDir[1] / m * lightNear; + nearPoint[2] = LightPos[2] + lightDir[2] / m * lightNear; + + sPlane[0] = lightDir[0] / d / m; + sPlane[1] = lightDir[1] / d / m; + sPlane[2] = lightDir[2] / d / m; + sPlane[3] = -(sPlane[0] * nearPoint[0] + + sPlane[1] * nearPoint[1] + + sPlane[2] * nearPoint[2]); + + glTexGenfv(GL_S, GL_EYE_PLANE, sPlane); + glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR); + glEnable(GL_TEXTURE_GEN_S); +} + + +static void +DisableTexgen(void) +{ + glDisable(GL_TEXTURE_GEN_S); + glDisable(GL_TEXTURE_GEN_T); + glDisable(GL_TEXTURE_GEN_R); + glDisable(GL_TEXTURE_GEN_Q); +} + + +static void +ComputeLightPos(GLfloat dist, GLfloat latitude, GLfloat longitude, + GLfloat pos[4], GLfloat dir[3]) +{ + + pos[0] = dist * sin(longitude * DEG_TO_RAD); + pos[1] = dist * sin(latitude * DEG_TO_RAD); + pos[2] = dist * cos(latitude * DEG_TO_RAD) * cos(longitude * DEG_TO_RAD); + pos[3] = 1; + dir[0] = -pos[0]; + dir[1] = -pos[1]; + dir[2] = -pos[2]; +} + + +static void +Display(void) +{ + GLfloat ar = (GLfloat) WindowWidth / (GLfloat) WindowHeight; + GLfloat d; + GLenum error; + + ComputeLightPos(LightDist, LightLatitude, LightLongitude, + LightPos, SpotDir); + /* + * Step 1: render scene from point of view of the light source + */ + /* compute frustum to enclose spot light cone */ + d = ShadowNear * tan(SpotAngle); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glFrustum(-d, d, -d, d, ShadowNear, ShadowFar); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + gluLookAt(LightPos[0], LightPos[1], LightPos[2], /* from */ + 0, 0, 0, /* target */ + 0, 1, 0); /* up */ + + glViewport(0, 0, ShadowTexWidth, ShadowTexHeight); + glClear(GL_DEPTH_BUFFER_BIT); + DrawScene(); + + /* + * Step 2: copy depth buffer into texture map + */ + if (DisplayMode == SHOW_DEPTH_MAPPING) { + /* load depth image as gray-scale luminance texture */ + GLfloat *depth = (GLfloat *) malloc(ShadowTexWidth * ShadowTexHeight + * sizeof(GLfloat)); + if (depth) { + glReadPixels(0, 0, ShadowTexWidth, ShadowTexHeight, + GL_DEPTH_COMPONENT, GL_FLOAT, depth); + glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, + ShadowTexWidth, ShadowTexHeight, 0, + GL_LUMINANCE, GL_FLOAT, depth); + free(depth); + } + } + else { + /* The normal shadow case */ + glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, + 0, 0, ShadowTexWidth, ShadowTexHeight, 0); + } + + /* + * Step 3: render scene from point of view of the camera + */ + glViewport(0, 0, WindowWidth, WindowHeight); + if (DisplayMode == SHOW_DEPTH_IMAGE) { + ShowDepthBuffer(WindowWidth, WindowHeight, 0, 1); + } + else { + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + glFrustum(-ar, ar, -1.0, 1.0, 4.0, 50.0); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef(0.0, 0.0, -22.0); + glRotatef(Xrot, 1, 0, 0); + glRotatef(Yrot, 0, 1, 0); + glRotatef(Zrot, 0, 0, 1); + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + glLightfv(GL_LIGHT0, GL_POSITION, LightPos); + if (LinearFilter) { + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + } + else { + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); + } + if (DisplayMode == SHOW_DEPTH_MAPPING) { +#if defined(GL_ARB_shadow) + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE); +#elif defined(GL_SGIX_shadow) + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_SGIX, GL_FALSE); +#endif + glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); + glEnable(GL_TEXTURE_2D); + MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar); + EnableIdentityTexgen(); + } + else if (DisplayMode == SHOW_DISTANCE) { + glMatrixMode(GL_TEXTURE); + glLoadIdentity(); + glMatrixMode(GL_MODELVIEW); + EnableDistanceTexgen(LightPos, SpotDir, ShadowNear+Bias, ShadowFar); + glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); + glEnable(GL_TEXTURE_1D); + } + else { + assert(DisplayMode == SHOW_NORMAL); +#if defined(GL_ARB_shadow) + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, + GL_COMPARE_R_TO_TEXTURE_ARB); +#elif defined(GL_SGIX_shadow) + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_SGIX, GL_TRUE); +#endif + glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); + glEnable(GL_TEXTURE_2D); + MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar); + EnableIdentityTexgen(); + } + DrawScene(); + DisableTexgen(); + glDisable(GL_TEXTURE_1D); + glDisable(GL_TEXTURE_2D); + } + + glutSwapBuffers(); + + error = glGetError(); + if (error) { + printf("GL Error: %s\n", (char *) gluErrorString(error)); + } +} + + +static void +Reshape(int width, int height) +{ + WindowWidth = width; + WindowHeight = height; + if (width >= 512 && height >= 512) { + ShadowTexWidth = ShadowTexHeight = 512; + } + else if (width >= 256 && height >= 256) { + ShadowTexWidth = ShadowTexHeight = 256; + } + else { + ShadowTexWidth = ShadowTexHeight = 128; + } + printf("Using %d x %d depth texture\n", ShadowTexWidth, ShadowTexHeight); +} + + +static void +Idle(void) +{ + static double t0 = -1.; + double dt, t = glutGet(GLUT_ELAPSED_TIME) / 1000.0; + if (t0 < 0.0) + t0 = t; + dt = t - t0; + t0 = t; + Yrot += 75.0 * dt; + /*LightLongitude -= 5.0;*/ + glutPostRedisplay(); +} + + +static void +Key(unsigned char key, int x, int y) +{ + const GLfloat step = 3.0; + (void) x; + (void) y; + switch (key) { + case 'a': + Anim = !Anim; + if (Anim) + glutIdleFunc(Idle); + else + glutIdleFunc(NULL); + break; + case 'b': + Bias -= 0.01; + printf("Bias %g\n", Bias); + break; + case 'B': + Bias += 0.01; + printf("Bias %g\n", Bias); + break; + case 'd': + DisplayMode = SHOW_DISTANCE; + break; + case 'f': + LinearFilter = !LinearFilter; + printf("%s filtering\n", LinearFilter ? "Bilinear" : "Nearest"); + break; + case 'i': + DisplayMode = SHOW_DEPTH_IMAGE; + break; + case 'm': + DisplayMode = SHOW_DEPTH_MAPPING; + break; + case 'n': + case ' ': + DisplayMode = SHOW_NORMAL; + break; + case 'o': + if (HaveEXTshadowFuncs) { + Operator++; + if (Operator >= 8) + Operator = 0; + printf("Operator: %s\n", OperatorName[Operator]); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB, + OperatorFunc[Operator]); + } + break; + case 'z': + Zrot -= step; + break; + case 'Z': + Zrot += step; + break; + case 27: + exit(0); + break; + } + glutPostRedisplay(); +} + + +static void +SpecialKey(int key, int x, int y) +{ + const GLfloat step = 3.0; + const int mod = glutGetModifiers(); + (void) x; + (void) y; + switch (key) { + case GLUT_KEY_UP: + if (mod) + LightLatitude += step; + else + Xrot += step; + break; + case GLUT_KEY_DOWN: + if (mod) + LightLatitude -= step; + else + Xrot -= step; + break; + case GLUT_KEY_LEFT: + if (mod) + LightLongitude += step; + else + Yrot += step; + break; + case GLUT_KEY_RIGHT: + if (mod) + LightLongitude -= step; + else + Yrot -= step; + break; + } + glutPostRedisplay(); +} + + +static void +Init(void) +{ +#if defined(GL_ARB_depth_texture) && defined(GL_ARB_shadow) + if (!glutExtensionSupported("GL_ARB_depth_texture") || + !glutExtensionSupported("GL_ARB_shadow")) { + printf("Sorry, this demo requires the GL_ARB_depth_texture and GL_ARB_shadow extensions\n"); + exit(1); + } + printf("Using GL_ARB_depth_texture and GL_ARB_shadow\n"); +#elif defined(GL_SGIX_depth_texture) && defined(GL_SGIX_shadow) + if (!glutExtensionSupported("GL_SGIX_depth_texture") || + !glutExtensionSupported("GL_SGIX_shadow")) { + printf("Sorry, this demo requires the GL_SGIX_depth_texture and GL_SGIX_shadow extensions\n"); + exit(1); + } + printf("Using GL_SGIX_depth_texture and GL_SGIX_shadow\n"); +#endif + HaveEXTshadowFuncs = glutExtensionSupported("GL_EXT_shadow_funcs"); + + glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP); + glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); +#if defined(GL_ARB_shadow) + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, + GL_COMPARE_R_TO_TEXTURE_ARB); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB, GL_LEQUAL); +#elif defined(GL_SGIX_shadow) + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_OPERATOR_SGIX, + GL_TEXTURE_LEQUAL_R_SGIX); +#endif + +#if defined(GL_ARB_shadow_ambient) + if (glutExtensionSupported("GL_ARB_shadow_ambient")) { + glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FAIL_VALUE_ARB, 0.3); + printf("and GL_ARB_shadow_ambient\n"); + } +#elif defined(GL_SGIX_shadow_ambient) + if (glutExtensionSupported("GL_SGIX_shadow_ambient")) { + glTexParameterf(GL_TEXTURE_2D, GL_SHADOW_AMBIENT_SGIX, 0.3); + printf("and GL_SGIX_shadow_ambient\n"); + } +#endif + + /* setup 1-D grayscale texture image for SHOW_DISTANCE mode */ + { + GLuint i; + GLubyte image[256]; + for (i = 0; i < 256; i++) + image[i] = i; + glTexImage1D(GL_TEXTURE_1D, 0, GL_LUMINANCE, + 256, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, image); + } + + glEnable(GL_DEPTH_TEST); + glEnable(GL_LIGHTING); + glEnable(GL_LIGHT0); +} + + +static void +PrintHelp(void) +{ + printf("Keys:\n"); + printf(" a = toggle animation\n"); + printf(" i = show depth texture image\n"); + printf(" m = show depth texture mapping\n"); + printf(" d = show fragment distance from light source\n"); + printf(" n = show normal, shadowed image\n"); + printf(" f = toggle nearest/bilinear texture filtering\n"); + printf(" b/B = decrease/increase shadow map Z bias\n"); + printf(" cursor keys = rotate scene\n"); + printf(" <shift> + cursor keys = rotate light source\n"); + if (HaveEXTshadowFuncs) + printf(" o = cycle through comparison modes\n"); +} + + +int +main(int argc, char *argv[]) +{ + glutInit(&argc, argv); + glutInitWindowPosition(0, 0); + glutInitWindowSize(WindowWidth, WindowHeight); + glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH); + glutCreateWindow(argv[0]); + glutReshapeFunc(Reshape); + glutKeyboardFunc(Key); + glutSpecialFunc(SpecialKey); + glutDisplayFunc(Display); + if (Anim) + glutIdleFunc(Idle); + Init(); + PrintHelp(); + glutMainLoop(); + return 0; +} |