diff options
Diffstat (limited to 'progs/demos/shadowtex.c')
| -rw-r--r-- | progs/demos/shadowtex.c | 1039 |
1 files changed, 0 insertions, 1039 deletions
diff --git a/progs/demos/shadowtex.c b/progs/demos/shadowtex.c deleted file mode 100644 index 677a42104f..0000000000 --- a/progs/demos/shadowtex.c +++ /dev/null @@ -1,1039 +0,0 @@ -/* - * Shadow demo using the GL_ARB_depth_texture, GL_ARB_shadow and - * GL_ARB_shadow_ambient extensions. - * - * Brian Paul - * 19 Feb 2001 - * - * Added GL_EXT_shadow_funcs support on 23 March 2002 - * Added GL_EXT_packed_depth_stencil support on 15 March 2006. - * Added GL_EXT_framebuffer_object support on 27 March 2006. - * Removed old SGIX extension support on 5 April 2006. - * Added vertex / fragment program support on 7 June 2007 (Ian Romanick). - * - * Copyright (C) 1999-2006 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 <string.h> -#include <math.h> -#include <GL/glew.h> -#include <GL/glut.h> - -#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 NeedNewShadowMap = GL_FALSE; -static GLuint ShadowTexture, GrayTexture; -static GLuint ShadowFBO; - -static GLfloat lightModelview[16]; -static GLfloat lightProjection[16]; - -static GLuint vert_prog; -static GLuint frag_progs[3]; -static GLuint curr_frag = 0; -static GLuint max_frag = 1; - -#define NUM_FRAG_MODES 3 -static const char *FragProgNames[] = { - "fixed-function", - "program without \"OPTION ARB_fragment_program_shadow\"", - "program with \"OPTION ARB_fragment_program_shadow\"", -}; - -static GLboolean HaveShadow = GL_FALSE; -static GLboolean HaveFBO = GL_FALSE; -static GLboolean UseFBO = GL_FALSE; -static GLboolean HaveVP = GL_FALSE; -static GLboolean HaveFP = GL_FALSE; -static GLboolean HaveFP_Shadow = GL_FALSE; -static GLboolean UseVP = GL_FALSE; -static GLboolean HavePackedDepthStencil = GL_FALSE; -static GLboolean UsePackedDepthStencil = GL_FALSE; -static GLboolean HaveEXTshadowFuncs = GL_FALSE; -static GLboolean HaveShadowAmbient = 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_SHADOWS 0 -#define SHOW_DEPTH_IMAGE 1 -#define SHOW_DEPTH_MAPPING 2 -#define SHOW_DISTANCE 3 - - - -#define MAT4_MUL(dest_vec, src_mat, src_vec) \ - "DP4 " dest_vec ".x, " src_mat "[0], " src_vec ";\n" \ - "DP4 " dest_vec ".y, " src_mat "[1], " src_vec ";\n" \ - "DP4 " dest_vec ".z, " src_mat "[2], " src_vec ";\n" \ - "DP4 " dest_vec ".w, " src_mat "[3], " src_vec ";\n" - -#define MAT3_MUL(dest_vec, src_mat, src_vec) \ - "DP3 " dest_vec ".x, " src_mat "[0], " src_vec ";\n" \ - "DP3 " dest_vec ".y, " src_mat "[1], " src_vec ";\n" \ - "DP3 " dest_vec ".z, " src_mat "[2], " src_vec ";\n" - -#define NORMALIZE(dest, src) \ - "DP3 " dest ".w, " src ", " src ";\n" \ - "RSQ " dest ".w, " dest ".w;\n" \ - "MUL " dest ", " src ", " dest ".w;\n" - -/** - * Vertex program for shadow mapping. - */ -static const char vert_code[] = - "!!ARBvp1.0\n" - "ATTRIB iPos = vertex.position;\n" - "ATTRIB iNorm = vertex.normal;\n" - - "PARAM mvinv[4] = { state.matrix.modelview.invtrans };\n" - "PARAM mvp[4] = { state.matrix.mvp };\n" - "PARAM mv[4] = { state.matrix.modelview };\n" - "PARAM texmat[4] = { state.matrix.texture[0] };\n" - "PARAM lightPos = state.light[0].position;\n" - "PARAM ambientCol = state.lightprod[0].ambient;\n" - "PARAM diffuseCol = state.lightprod[0].diffuse;\n" - - "TEMP n, lightVec;\n" - "ALIAS V = lightVec;\n" - "ALIAS NdotL = n;\n" - - "OUTPUT oPos = result.position;\n" - "OUTPUT oColor = result.color;\n" - "OUTPUT oTex = result.texcoord[0];\n" - - /* Transform the vertex to clip coordinates. */ - MAT4_MUL("oPos", "mvp", "iPos") - - /* Transform the vertex to eye coordinates. */ - MAT4_MUL("V", "mv", "iPos") - - /* Transform the vertex to projected light coordinates. */ - MAT4_MUL("oTex", "texmat", "iPos") - - /* Transform the normal to eye coordinates. */ - MAT3_MUL("n", "mvinv", "iNorm") - - /* Calculate the vector from the vertex to the light in eye - * coordinates. - */ - "SUB lightVec, lightPos, V;\n" - NORMALIZE("lightVec", "lightVec") - - /* Compute diffuse lighting coefficient. - */ - "DP3 NdotL.x, n, lightVec;\n" - "MAX NdotL.x, NdotL.x, {0.0};\n" - "MIN NdotL.x, NdotL.x, {1.0};\n" - - /* Accumulate color contributions. - */ - "MOV oColor, diffuseCol;\n" - "MAD oColor.xyz, NdotL.x, diffuseCol, ambientCol;\n" - "END\n" - ; - -static const char frag_code[] = - "!!ARBfp1.0\n" - - "TEMP shadow, temp;\n" - - "TXP shadow, fragment.texcoord[0], texture[0], 2D;\n" - "RCP temp.x, fragment.texcoord[0].w;\n" - "MUL temp.x, temp.x, fragment.texcoord[0].z;\n" - "SGE shadow, shadow.x, temp.x;\n" - "MUL result.color.rgb, fragment.color, shadow.x;\n" - "MOV result.color.a, fragment.color;\n" - "END\n" - ; - -static const char frag_shadow_code[] = - "!!ARBfp1.0\n" - "OPTION ARB_fragment_program_shadow;\n" - - "TEMP shadow;\n" - - "TXP shadow, fragment.texcoord[0], texture[0], SHADOW2D;\n" - "MUL result.color.rgb, fragment.color, shadow.x;\n" - "MOV result.color.a, fragment.color.a;\n" - "END\n" - ; - -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(); -} - - -/** - * Calculate modelview and project matrices for the light - * - * Stores the results in \c lightProjection (projection matrix) and - * \c lightModelview (modelview matrix). - */ -static void -MakeShadowMatrix(const GLfloat lightPos[4], const GLfloat spotDir[3], - GLfloat spotAngle, GLfloat shadowNear, GLfloat shadowFar) -{ - /* compute frustum to enclose spot light cone */ - const GLfloat d = shadowNear * tan(spotAngle); - - glMatrixMode(GL_PROJECTION); - glPushMatrix(); - glLoadIdentity(); - glFrustum(-d, d, -d, d, shadowNear, shadowFar); - glGetFloatv(GL_PROJECTION_MATRIX, lightProjection); - glPopMatrix(); - - glMatrixMode(GL_MODELVIEW); - glPushMatrix(); - glLoadIdentity(); - gluLookAt(lightPos[0], lightPos[1], lightPos[2], - lightPos[0] + spotDir[0], - lightPos[1] + spotDir[1], - lightPos[2] + spotDir[2], - 0.0, 1.0, 0.0); - glGetFloatv(GL_MODELVIEW_MATRIX, lightModelview); - glPopMatrix(); -} - - -/** - * Load \c GL_TEXTURE matrix with light's MVP matrix. - */ -static void SetShadowTextureMatrix(void) -{ - static const GLfloat biasMatrix[16] = { - 0.5, 0.0, 0.0, 0.0, - 0.0, 0.5, 0.0, 0.0, - 0.0, 0.0, 0.5, 0.0, - 0.5, 0.5, 0.5, 1.0, - }; - - glMatrixMode(GL_TEXTURE); - glLoadMatrixf(biasMatrix); - glTranslatef(0.0, 0.0, Bias); - glMultMatrixf(lightProjection); - glMultMatrixf(lightModelview); - 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]; -} - - -/** - * Render the shadow map / depth texture. - * The result will be in the texture object named ShadowTexture. - */ -static void -RenderShadowMap(void) -{ - GLenum depthFormat; /* GL_DEPTH_COMPONENT or GL_DEPTH_STENCIL_EXT */ - GLenum depthType; /* GL_UNSIGNED_INT_24_8_EXT or GL_UNSIGNED_INT */ - - if (WindowWidth >= 1024 && WindowHeight >= 1024) { - ShadowTexWidth = ShadowTexHeight = 1024; - } - else if (WindowWidth >= 512 && WindowHeight >= 512) { - ShadowTexWidth = ShadowTexHeight = 512; - } - else if (WindowWidth >= 256 && WindowHeight >= 256) { - ShadowTexWidth = ShadowTexHeight = 256; - } - else { - ShadowTexWidth = ShadowTexHeight = 128; - } - printf("Rendering %d x %d depth texture\n", ShadowTexWidth, ShadowTexHeight); - - if (UsePackedDepthStencil) { - depthFormat = GL_DEPTH_STENCIL_EXT; - depthType = GL_UNSIGNED_INT_24_8_EXT; - } - else { - depthFormat = GL_DEPTH_COMPONENT; - depthType = GL_UNSIGNED_INT; - } - - glMatrixMode(GL_PROJECTION); - glLoadMatrixf(lightProjection); - - glMatrixMode(GL_MODELVIEW); - glLoadMatrixf(lightModelview); - - if (UseFBO) { - GLenum fbo_status; - - glTexImage2D(GL_TEXTURE_2D, 0, depthFormat, - ShadowTexWidth, ShadowTexHeight, 0, - depthFormat, depthType, NULL); - - /* Set the filter mode so that the texture is texture-complete. - * Otherwise it will cause the framebuffer to fail the framebuffer - * completeness test. - */ - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); - - glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, ShadowFBO); - glDrawBuffer(GL_NONE); - glReadBuffer(GL_NONE); - - fbo_status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT); - if (fbo_status != GL_FRAMEBUFFER_COMPLETE_EXT) { - fprintf(stderr, "FBO not complete! status = 0x%04x\n", fbo_status); - assert(fbo_status == GL_FRAMEBUFFER_COMPLETE_EXT); - } - } - - assert(!glIsEnabled(GL_TEXTURE_1D)); - assert(!glIsEnabled(GL_TEXTURE_2D)); - - glViewport(0, 0, ShadowTexWidth, ShadowTexHeight); - glClear(GL_DEPTH_BUFFER_BIT); - glEnable(GL_DEPTH_TEST); - DrawScene(); - - if (UseFBO) { - /* all done! */ - glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); - } - else { - /* - * copy depth buffer into the texture map - */ - if (DisplayMode == SHOW_DEPTH_MAPPING) { - /* load depth image as gray-scale luminance texture */ - GLuint *depth = (GLuint *) - malloc(ShadowTexWidth * ShadowTexHeight * sizeof(GLuint)); - assert(depth); - glReadPixels(0, 0, ShadowTexWidth, ShadowTexHeight, - depthFormat, depthType, depth); - glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, - ShadowTexWidth, ShadowTexHeight, 0, - GL_LUMINANCE, GL_UNSIGNED_INT, depth); - free(depth); - } - else { - /* The normal shadow case - a real depth texture */ - glCopyTexImage2D(GL_TEXTURE_2D, 0, depthFormat, - 0, 0, ShadowTexWidth, ShadowTexHeight, 0); - if (UsePackedDepthStencil) { - /* debug check */ - GLint intFormat; - glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, - GL_TEXTURE_INTERNAL_FORMAT, &intFormat); - assert(intFormat == GL_DEPTH_STENCIL_EXT); - } - } - } -} - - -/** - * Show the shadow map as a grayscale image. - */ -static void -ShowShadowMap(void) -{ - glClear(GL_COLOR_BUFFER_BIT); - - glMatrixMode(GL_TEXTURE); - glLoadIdentity(); - - glMatrixMode(GL_PROJECTION); - glLoadIdentity(); - glOrtho(0, WindowWidth, 0, WindowHeight, -1, 1); - - glMatrixMode(GL_MODELVIEW); - glLoadIdentity(); - - glDisable(GL_DEPTH_TEST); - glDisable(GL_LIGHTING); - - glEnable(GL_TEXTURE_2D); - - DisableTexgen(); - - /* interpret texture's depth values as luminance values */ - if (HaveShadow) { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE); - } - - glTexParameteri(GL_TEXTURE_2D, GL_DEPTH_TEXTURE_MODE_ARB, GL_LUMINANCE); - glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); - - glBegin(GL_POLYGON); - glTexCoord2f(0, 0); glVertex2f(0, 0); - glTexCoord2f(1, 0); glVertex2f(ShadowTexWidth, 0); - glTexCoord2f(1, 1); glVertex2f(ShadowTexWidth, ShadowTexHeight); - glTexCoord2f(0, 1); glVertex2f(0, ShadowTexHeight); - glEnd(); - - glDisable(GL_TEXTURE_2D); - glEnable(GL_DEPTH_TEST); - glEnable(GL_LIGHTING); -} - - -/** - * Redraw window image - */ -static void -Display(void) -{ - GLenum error; - - ComputeLightPos(LightDist, LightLatitude, LightLongitude, - LightPos, SpotDir); - - if (NeedNewShadowMap) { - MakeShadowMatrix(LightPos, SpotDir, SpotAngle, ShadowNear, ShadowFar); - RenderShadowMap(); - NeedNewShadowMap = GL_FALSE; - } - - glViewport(0, 0, WindowWidth, WindowHeight); - if (DisplayMode == SHOW_DEPTH_IMAGE) { - ShowShadowMap(); - } - else { - /* prepare to draw scene from camera's view */ - const GLfloat ar = (GLfloat) WindowWidth / (GLfloat) WindowHeight; - - 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 (HaveShadow) { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, GL_NONE); - } - glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); - glEnable(GL_TEXTURE_2D); - - SetShadowTextureMatrix(); - 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); - assert(!glIsEnabled(GL_TEXTURE_2D)); - } - else { - assert(DisplayMode == SHOW_SHADOWS); - if (HaveShadow) { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE_ARB, - GL_COMPARE_R_TO_TEXTURE_ARB); - } - - if (curr_frag > 0) { - glEnable(GL_FRAGMENT_PROGRAM_ARB); - } - else { - glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); - } - glEnable(GL_TEXTURE_2D); - - SetShadowTextureMatrix(); - - if (UseVP) { - glEnable(GL_VERTEX_PROGRAM_ARB); - } - else { - glEnable(GL_LIGHTING); - EnableIdentityTexgen(); - } - } - - DrawScene(); - - if (UseVP) { - glDisable(GL_VERTEX_PROGRAM_ARB); - } - else { - DisableTexgen(); - glDisable(GL_LIGHTING); - } - - if (curr_frag > 0) { - glDisable(GL_FRAGMENT_PROGRAM_ARB); - } - - 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; - NeedNewShadowMap = GL_TRUE; -} - - -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 'M': - curr_frag = (1 + curr_frag) % max_frag; - if (!HaveShadow && (curr_frag == 0)) { - curr_frag = 1; - } - - printf("Using fragment %s\n", FragProgNames[curr_frag]); - - if (HaveFP) { - glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, frag_progs[curr_frag]); - } - break; - case 'n': - case 's': - case ' ': - DisplayMode = SHOW_SHADOWS; - break; - case 'o': - if (HaveEXTshadowFuncs) { - Operator++; - if (Operator >= 8) - Operator = 0; - printf("Operator: %s\n", OperatorName[Operator]); - if (HaveShadow) { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC_ARB, - OperatorFunc[Operator]); - } - } - break; - case 'p': - UsePackedDepthStencil = !UsePackedDepthStencil; - if (UsePackedDepthStencil && !HavePackedDepthStencil) { - printf("Sorry, GL_EXT_packed_depth_stencil not supported\n"); - UsePackedDepthStencil = GL_FALSE; - } - else { - printf("Use GL_DEPTH_STENCIL_EXT: %d\n", UsePackedDepthStencil); - /* Don't really need to regenerate shadow map texture, but do so - * to exercise more code more often. - */ - NeedNewShadowMap = GL_TRUE; - } - break; - case 'v': - UseVP = !UseVP && HaveVP; - printf("Using vertex %s mode.\n", - UseVP ? "program" : "fixed-function"); - break; - case 'z': - Zrot -= step; - break; - case 'Z': - Zrot += step; - break; - case 27: - exit(0); - break; - } - fflush(stdout); - 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; - } - if (mod) - NeedNewShadowMap = GL_TRUE; - - glutPostRedisplay(); -} - - -/* A helper for finding errors in program strings */ -static int FindLine( const char *program, int position ) -{ - int i, line = 1; - for (i = 0; i < position; i++) { - if (program[i] == '\n') - line++; - } - return line; -} - - -static GLuint -compile_program(GLenum target, const char *code) -{ - GLuint p; - GLint errorPos; - - - glGenProgramsARB(1, & p); - - glBindProgramARB(target, p); - glProgramStringARB(target, GL_PROGRAM_FORMAT_ASCII_ARB, - strlen(code), code); - glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorPos); - if (glGetError() != GL_NO_ERROR || errorPos != -1) { - int l = FindLine(code, errorPos); - printf("Fragment Program Error (pos=%d line=%d): %s\n", errorPos, l, - (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB)); - exit(0); - } - - glBindProgramARB(target, 0); - return p; -} - -static void -Init(void) -{ - static const GLfloat borderColor[4] = {1.0, 0.0, 0.0, 0.0}; - - if (!glutExtensionSupported("GL_ARB_depth_texture")) { - printf("Sorry, this demo requires the GL_ARB_depth_texture extension\n"); - exit(1); - } - - HaveShadow = glutExtensionSupported("GL_ARB_shadow"); - HaveVP = glutExtensionSupported("GL_ARB_vertex_program"); - HaveFP = glutExtensionSupported("GL_ARB_fragment_program"); - HaveFP_Shadow = glutExtensionSupported("GL_ARB_fragment_program_shadow"); - - if (!HaveShadow && !HaveFP) { - printf("Sorry, this demo requires either the GL_ARB_shadow extension " - "or the GL_ARB_fragment_program extension\n"); - exit(1); - } - - printf("Using GL_ARB_depth_texture\n"); - if (HaveShadow) { - printf("and GL_ARB_shadow\n"); - } - - if (HaveFP) { - printf("and GL_ARB_fragment_program\n"); - } - - HaveShadowAmbient = glutExtensionSupported("GL_ARB_shadow_ambient"); - if (HaveShadowAmbient) { - printf("and GL_ARB_shadow_ambient\n"); - } - - HaveEXTshadowFuncs = glutExtensionSupported("GL_EXT_shadow_funcs"); - - HavePackedDepthStencil = glutExtensionSupported("GL_EXT_packed_depth_stencil"); - UsePackedDepthStencil = HavePackedDepthStencil; - -#if defined(GL_EXT_framebuffer_object) - HaveFBO = glutExtensionSupported("GL_EXT_framebuffer_object"); - UseFBO = HaveFBO; - if (UseFBO) { - printf("Using GL_EXT_framebuffer_object\n"); - } -#endif - - /* - * Set up the 2D shadow map texture - */ - glGenTextures(1, &ShadowTexture); - glBindTexture(GL_TEXTURE_2D, ShadowTexture); - glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); - - if (HaveShadow) { - 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); - } - - if (HaveShadowAmbient) { - glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FAIL_VALUE_ARB, 0.3); - } - -#if defined(GL_EXT_framebuffer_object) - if (UseFBO) { - glGenFramebuffersEXT(1, &ShadowFBO); - glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, ShadowFBO); - glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, - GL_COLOR_ATTACHMENT0_EXT, - GL_RENDERBUFFER_EXT, 0); - glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, - GL_TEXTURE_2D, ShadowTexture, 0); - - glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); - } -#endif - - /* - * Setup 1-D grayscale texture image for SHOW_DISTANCE mode - */ - glGenTextures(1, &GrayTexture); - glBindTexture(GL_TEXTURE_1D, GrayTexture); - 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); - { - 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); - } - - if (HaveVP) { - vert_prog = compile_program(GL_VERTEX_PROGRAM_ARB, vert_code); - glBindProgramARB(GL_VERTEX_PROGRAM_ARB, vert_prog); - } - - max_frag = 1; - frag_progs[0] = 0; - - if (HaveFP) { - frag_progs[1] = compile_program(GL_FRAGMENT_PROGRAM_ARB, frag_code); - max_frag = 2; - } - - if (HaveFP && HaveFP_Shadow) { - frag_progs[2] = compile_program(GL_FRAGMENT_PROGRAM_ARB, - frag_shadow_code); - max_frag = 3; - } - - if (!HaveShadow) { - curr_frag = 1; - glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, frag_progs[curr_frag]); - } - - 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(" p = toggle use of packed depth/stencil\n"); - printf(" M = cycle through fragment program modes\n"); - printf(" v = toggle vertex program modes\n"); - printf(" cursor keys = rotate scene\n"); - printf(" <shift> + cursor keys = rotate light source\n"); - if (HaveEXTshadowFuncs) - printf(" o = cycle through comparison modes\n"); - fflush(stdout); -} - - -int -main(int argc, char *argv[]) -{ - glutInitWindowSize(WindowWidth, WindowHeight); - glutInit(&argc, argv); - glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL); - glutCreateWindow(argv[0]); - glewInit(); - glutReshapeFunc(Reshape); - glutKeyboardFunc(Key); - glutSpecialFunc(SpecialKey); - glutDisplayFunc(Display); - if (Anim) - glutIdleFunc(Idle); - Init(); - PrintHelp(); - glutMainLoop(); - return 0; -} |