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Diffstat (limited to 'progs/tests/dinoshade.c')
| -rw-r--r-- | progs/tests/dinoshade.c | 914 |
1 files changed, 0 insertions, 914 deletions
diff --git a/progs/tests/dinoshade.c b/progs/tests/dinoshade.c deleted file mode 100644 index ed7b879bc71..00000000000 --- a/progs/tests/dinoshade.c +++ /dev/null @@ -1,914 +0,0 @@ - -/* Copyright (c) Mark J. Kilgard, 1994, 1997. */ - -/* This program is freely distributable without licensing fees - and is provided without guarantee or warrantee expressed or - implied. This program is -not- in the public domain. */ - -/* Example for PC game developers to show how to *combine* texturing, - reflections, and projected shadows all in real-time with OpenGL. - Robust reflections use stenciling. Robust projected shadows - use both stenciling and polygon offset. PC game programmers - should realize that neither stenciling nor polygon offset are - supported by Direct3D, so these real-time rendering algorithms - are only really viable with OpenGL. - - The program has modes for disabling the stenciling and polygon - offset uses. It is worth running this example with these features - toggled off so you can see the sort of artifacts that result. - - Notice that the floor texturing, reflections, and shadowing - all co-exist properly. */ - -/* When you run this program: Left mouse button controls the - view. Middle mouse button controls light position (left & - right rotates light around dino; up & down moves light - position up and down). Right mouse button pops up menu. */ - -/* Check out the comments in the "redraw" routine to see how the - reflection blending and surface stenciling is done. You can - also see in "redraw" how the projected shadows are rendered, - including the use of stenciling and polygon offset. */ - -/* This program is derived from glutdino.c */ - -/* Compile: cc -o dinoshade dinoshade.c -lglut -lGLU -lGL -lXmu -lXext -lX11 -lm */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <math.h> /* for cos(), sin(), and sqrt() */ -#ifdef __VMS -# include <stddef.h> /* for ptrdiff_t, referenced by GL.h when GL_GLEXT_LEGACY defined */ -#else -# include <malloc.h> /* for ptrdiff_t, referenced by GL.h when GL_GLEXT_LEGACY defined */ -#endif -#ifdef _WIN32 -#include <windows.h> -#endif -#define GL_GLEXT_LEGACY -#include <GL/glut.h> /* OpenGL Utility Toolkit header */ - -/* Some <math.h> files do not define M_PI... */ -#ifndef M_PI -#define M_PI 3.14159265358979323846 -#endif - -/* Variable controlling various rendering modes. */ -static int stencilReflection = 1, stencilShadow = 1, offsetShadow = 1; -static int renderShadow = 1, renderDinosaur = 1, renderReflection = 1; -static int linearFiltering = 0, useMipmaps = 0, useTexture = 1; -static int reportSpeed = 0; -static int animation = 1; -static GLboolean lightSwitch = GL_TRUE; -static int directionalLight = 1; -static int forceExtension = 0; - -/* Time varying or user-controled variables. */ -static float jump = 0.0; -static float lightAngle = 0.0, lightHeight = 20; -GLfloat angle = -150; /* in degrees */ -GLfloat angle2 = 30; /* in degrees */ - -int moving, startx, starty; -int lightMoving = 0, lightStartX, lightStartY; - -enum { - MISSING, EXTENSION, ONE_DOT_ONE -}; -int polygonOffsetVersion; - -static GLdouble bodyWidth = 3.0; -/* *INDENT-OFF* */ -static GLfloat body[][2] = { {0, 3}, {1, 1}, {5, 1}, {8, 4}, {10, 4}, {11, 5}, - {11, 11.5}, {13, 12}, {13, 13}, {10, 13.5}, {13, 14}, {13, 15}, {11, 16}, - {8, 16}, {7, 15}, {7, 13}, {8, 12}, {7, 11}, {6, 6}, {4, 3}, {3, 2}, - {1, 2} }; -static GLfloat arm[][2] = { {8, 10}, {9, 9}, {10, 9}, {13, 8}, {14, 9}, {16, 9}, - {15, 9.5}, {16, 10}, {15, 10}, {15.5, 11}, {14.5, 10}, {14, 11}, {14, 10}, - {13, 9}, {11, 11}, {9, 11} }; -static GLfloat leg[][2] = { {8, 6}, {8, 4}, {9, 3}, {9, 2}, {8, 1}, {8, 0.5}, {9, 0}, - {12, 0}, {10, 1}, {10, 2}, {12, 4}, {11, 6}, {10, 7}, {9, 7} }; -static GLfloat eye[][2] = { {8.75, 15}, {9, 14.7}, {9.6, 14.7}, {10.1, 15}, - {9.6, 15.25}, {9, 15.25} }; -static GLfloat lightPosition[4]; -static GLfloat lightColor[] = {0.8, 1.0, 0.8, 1.0}; /* green-tinted */ -static GLfloat skinColor[] = {0.1, 1.0, 0.1, 1.0}, eyeColor[] = {1.0, 0.2, 0.2, 1.0}; -/* *INDENT-ON* */ - -/* Nice floor texture tiling pattern. */ -static char *circles[] = { - "....xxxx........", - "..xxxxxxxx......", - ".xxxxxxxxxx.....", - ".xxx....xxx.....", - "xxx......xxx....", - "xxx......xxx....", - "xxx......xxx....", - "xxx......xxx....", - ".xxx....xxx.....", - ".xxxxxxxxxx.....", - "..xxxxxxxx......", - "....xxxx........", - "................", - "................", - "................", - "................", -}; - -static void -makeFloorTexture(void) -{ - GLubyte floorTexture[16][16][3]; - GLubyte *loc; - int s, t; - - /* Setup RGB image for the texture. */ - loc = (GLubyte*) floorTexture; - for (t = 0; t < 16; t++) { - for (s = 0; s < 16; s++) { - if (circles[t][s] == 'x') { - /* Nice green. */ - loc[0] = 0x1f; - loc[1] = 0x8f; - loc[2] = 0x1f; - } else { - /* Light gray. */ - loc[0] = 0xaa; - loc[1] = 0xaa; - loc[2] = 0xaa; - } - loc += 3; - } - } - - glPixelStorei(GL_UNPACK_ALIGNMENT, 1); - - if (useMipmaps) { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, - GL_LINEAR_MIPMAP_LINEAR); - gluBuild2DMipmaps(GL_TEXTURE_2D, 3, 16, 16, - GL_RGB, GL_UNSIGNED_BYTE, floorTexture); - } else { - if (linearFiltering) { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); - } else { - glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); - } - glTexImage2D(GL_TEXTURE_2D, 0, 3, 16, 16, 0, - GL_RGB, GL_UNSIGNED_BYTE, floorTexture); - } -} - -enum { - X, Y, Z, W -}; -enum { - A, B, C, D -}; - -/* Create a matrix that will project the desired shadow. */ -void -shadowMatrix(GLfloat shadowMat[4][4], - GLfloat groundplane[4], - GLfloat lightpos[4]) -{ - GLfloat dot; - - /* Find dot product between light position vector and ground plane normal. */ - dot = groundplane[X] * lightpos[X] + - groundplane[Y] * lightpos[Y] + - groundplane[Z] * lightpos[Z] + - groundplane[W] * lightpos[W]; - - shadowMat[0][0] = dot - lightpos[X] * groundplane[X]; - shadowMat[1][0] = 0.f - lightpos[X] * groundplane[Y]; - shadowMat[2][0] = 0.f - lightpos[X] * groundplane[Z]; - shadowMat[3][0] = 0.f - lightpos[X] * groundplane[W]; - - shadowMat[X][1] = 0.f - lightpos[Y] * groundplane[X]; - shadowMat[1][1] = dot - lightpos[Y] * groundplane[Y]; - shadowMat[2][1] = 0.f - lightpos[Y] * groundplane[Z]; - shadowMat[3][1] = 0.f - lightpos[Y] * groundplane[W]; - - shadowMat[X][2] = 0.f - lightpos[Z] * groundplane[X]; - shadowMat[1][2] = 0.f - lightpos[Z] * groundplane[Y]; - shadowMat[2][2] = dot - lightpos[Z] * groundplane[Z]; - shadowMat[3][2] = 0.f - lightpos[Z] * groundplane[W]; - - shadowMat[X][3] = 0.f - lightpos[W] * groundplane[X]; - shadowMat[1][3] = 0.f - lightpos[W] * groundplane[Y]; - shadowMat[2][3] = 0.f - lightpos[W] * groundplane[Z]; - shadowMat[3][3] = dot - lightpos[W] * groundplane[W]; - -} - -/* Find the plane equation given 3 points. */ -void -findPlane(GLfloat plane[4], - GLfloat v0[3], GLfloat v1[3], GLfloat v2[3]) -{ - GLfloat vec0[3], vec1[3]; - - /* Need 2 vectors to find cross product. */ - vec0[X] = v1[X] - v0[X]; - vec0[Y] = v1[Y] - v0[Y]; - vec0[Z] = v1[Z] - v0[Z]; - - vec1[X] = v2[X] - v0[X]; - vec1[Y] = v2[Y] - v0[Y]; - vec1[Z] = v2[Z] - v0[Z]; - - /* find cross product to get A, B, and C of plane equation */ - plane[A] = vec0[Y] * vec1[Z] - vec0[Z] * vec1[Y]; - plane[B] = -(vec0[X] * vec1[Z] - vec0[Z] * vec1[X]); - plane[C] = vec0[X] * vec1[Y] - vec0[Y] * vec1[X]; - - plane[D] = -(plane[A] * v0[X] + plane[B] * v0[Y] + plane[C] * v0[Z]); -} - -void -extrudeSolidFromPolygon(GLfloat data[][2], unsigned int dataSize, - GLdouble thickness, GLuint side, GLuint edge, GLuint whole) -{ - static GLUtriangulatorObj *tobj = NULL; - GLdouble vertex[3], dx, dy, len; - int i; - int count = (int) (dataSize / (2 * sizeof(GLfloat))); - - if (tobj == NULL) { - tobj = gluNewTess(); /* create and initialize a GLU - polygon tesselation object */ - gluTessCallback(tobj, GLU_BEGIN, glBegin); - gluTessCallback(tobj, GLU_VERTEX, glVertex2fv); /* semi-tricky */ - gluTessCallback(tobj, GLU_END, glEnd); - } - glNewList(side, GL_COMPILE); - glShadeModel(GL_SMOOTH); /* smooth minimizes seeing - tessellation */ - gluBeginPolygon(tobj); - for (i = 0; i < count; i++) { - vertex[0] = data[i][0]; - vertex[1] = data[i][1]; - vertex[2] = 0; - gluTessVertex(tobj, vertex, data[i]); - } - gluEndPolygon(tobj); - glEndList(); - glNewList(edge, GL_COMPILE); - glShadeModel(GL_FLAT); /* flat shade keeps angular hands - from being "smoothed" */ - glBegin(GL_QUAD_STRIP); - for (i = 0; i <= count; i++) { -#if 1 /* weird, but seems to be legal */ - /* mod function handles closing the edge */ - glVertex3f(data[i % count][0], data[i % count][1], 0.0); - glVertex3f(data[i % count][0], data[i % count][1], thickness); - /* Calculate a unit normal by dividing by Euclidean - distance. We * could be lazy and use - glEnable(GL_NORMALIZE) so we could pass in * arbitrary - normals for a very slight performance hit. */ - dx = data[(i + 1) % count][1] - data[i % count][1]; - dy = data[i % count][0] - data[(i + 1) % count][0]; - len = sqrt(dx * dx + dy * dy); - glNormal3f(dx / len, dy / len, 0.0); -#else /* the nice way of doing it */ - /* Calculate a unit normal by dividing by Euclidean - distance. We * could be lazy and use - glEnable(GL_NORMALIZE) so we could pass in * arbitrary - normals for a very slight performance hit. */ - dx = data[i % count][1] - data[(i - 1 + count) % count][1]; - dy = data[(i - 1 + count) % count][0] - data[i % count][0]; - len = sqrt(dx * dx + dy * dy); - glNormal3f(dx / len, dy / len, 0.0); - /* mod function handles closing the edge */ - glVertex3f(data[i % count][0], data[i % count][1], 0.0); - glVertex3f(data[i % count][0], data[i % count][1], thickness); -#endif - } - glEnd(); - glEndList(); - glNewList(whole, GL_COMPILE); - glFrontFace(GL_CW); - glCallList(edge); - glNormal3f(0.0, 0.0, -1.0); /* constant normal for side */ - glCallList(side); - glPushMatrix(); - glTranslatef(0.0, 0.0, thickness); - glFrontFace(GL_CCW); - glNormal3f(0.0, 0.0, 1.0); /* opposite normal for other side */ - glCallList(side); - glPopMatrix(); - glEndList(); -} - -/* Enumerants for refering to display lists. */ -typedef enum { - RESERVED, BODY_SIDE, BODY_EDGE, BODY_WHOLE, ARM_SIDE, ARM_EDGE, ARM_WHOLE, - LEG_SIDE, LEG_EDGE, LEG_WHOLE, EYE_SIDE, EYE_EDGE, EYE_WHOLE -} displayLists; - -static void -makeDinosaur(void) -{ - extrudeSolidFromPolygon(body, sizeof(body), bodyWidth, - BODY_SIDE, BODY_EDGE, BODY_WHOLE); - extrudeSolidFromPolygon(arm, sizeof(arm), bodyWidth / 4, - ARM_SIDE, ARM_EDGE, ARM_WHOLE); - extrudeSolidFromPolygon(leg, sizeof(leg), bodyWidth / 2, - LEG_SIDE, LEG_EDGE, LEG_WHOLE); - extrudeSolidFromPolygon(eye, sizeof(eye), bodyWidth + 0.2, - EYE_SIDE, EYE_EDGE, EYE_WHOLE); -} - -static void -drawDinosaur(void) - -{ - glPushMatrix(); - /* Translate the dinosaur to be at (0,8,0). */ - glTranslatef(-8, 0, -bodyWidth / 2); - glTranslatef(0.0, jump, 0.0); - glMaterialfv(GL_FRONT, GL_DIFFUSE, skinColor); - glCallList(BODY_WHOLE); - glTranslatef(0.0, 0.0, bodyWidth); - glCallList(ARM_WHOLE); - glCallList(LEG_WHOLE); - glTranslatef(0.0, 0.0, -bodyWidth - bodyWidth / 4); - glCallList(ARM_WHOLE); - glTranslatef(0.0, 0.0, -bodyWidth / 4); - glCallList(LEG_WHOLE); - glTranslatef(0.0, 0.0, bodyWidth / 2 - 0.1); - glMaterialfv(GL_FRONT, GL_DIFFUSE, eyeColor); - glCallList(EYE_WHOLE); - glPopMatrix(); -} - -static GLfloat floorVertices[4][3] = { - { -20.0, 0.0, 20.0 }, - { 20.0, 0.0, 20.0 }, - { 20.0, 0.0, -20.0 }, - { -20.0, 0.0, -20.0 }, -}; - -/* Draw a floor (possibly textured). */ -static void -drawFloor(void) -{ - glDisable(GL_LIGHTING); - - if (useTexture) { - glEnable(GL_TEXTURE_2D); - } - - glBegin(GL_QUADS); - glTexCoord2f(0.0, 0.0); - glVertex3fv(floorVertices[0]); - glTexCoord2f(0.0, 16.0); - glVertex3fv(floorVertices[1]); - glTexCoord2f(16.0, 16.0); - glVertex3fv(floorVertices[2]); - glTexCoord2f(16.0, 0.0); - glVertex3fv(floorVertices[3]); - glEnd(); - - if (useTexture) { - glDisable(GL_TEXTURE_2D); - } - - glEnable(GL_LIGHTING); -} - -static GLfloat floorPlane[4]; -static GLfloat floorShadow[4][4]; - -static void -redraw(void) -{ - int start, end; - - if (reportSpeed) { - start = glutGet(GLUT_ELAPSED_TIME); - } - - /* Clear; default stencil clears to zero. */ - if ((stencilReflection && renderReflection) || (stencilShadow && renderShadow)) { - glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); - } else { - /* Avoid clearing stencil when not using it. */ - glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); - } - - /* Reposition the light source. */ - lightPosition[0] = 12*cos(lightAngle); - lightPosition[1] = lightHeight; - lightPosition[2] = 12*sin(lightAngle); - if (directionalLight) { - lightPosition[3] = 0.0; - } else { - lightPosition[3] = 1.0; - } - - shadowMatrix(floorShadow, floorPlane, lightPosition); - - glPushMatrix(); - /* Perform scene rotations based on user mouse input. */ - glRotatef(angle2, 1.0, 0.0, 0.0); - glRotatef(angle, 0.0, 1.0, 0.0); - - /* Tell GL new light source position. */ - glLightfv(GL_LIGHT0, GL_POSITION, lightPosition); - - if (renderReflection) { - if (stencilReflection) { - /* We can eliminate the visual "artifact" of seeing the "flipped" - dinosaur underneath the floor by using stencil. The idea is - draw the floor without color or depth update but so that - a stencil value of one is where the floor will be. Later when - rendering the dinosaur reflection, we will only update pixels - with a stencil value of 1 to make sure the reflection only - lives on the floor, not below the floor. */ - - /* Don't update color or depth. */ - glDisable(GL_DEPTH_TEST); - glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE); - - /* Draw 1 into the stencil buffer. */ - glEnable(GL_STENCIL_TEST); - glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE); - glStencilFunc(GL_ALWAYS, 1, 0xffffffff); - - /* Now render floor; floor pixels just get their stencil set to 1. */ - drawFloor(); - - /* Re-enable update of color and depth. */ - glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE); - glEnable(GL_DEPTH_TEST); - - /* Now, only render where stencil is set to 1. */ - glStencilFunc(GL_EQUAL, 1, 0xffffffff); /* draw if ==1 */ - glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP); - } - - glPushMatrix(); - - /* The critical reflection step: Reflect dinosaur through the floor - (the Y=0 plane) to make a relection. */ - glScalef(1.0, -1.0, 1.0); - - /* Reflect the light position. */ - glLightfv(GL_LIGHT0, GL_POSITION, lightPosition); - - /* To avoid our normals getting reversed and hence botched lighting - on the reflection, turn on normalize. */ - glEnable(GL_NORMALIZE); - glCullFace(GL_FRONT); - - /* Draw the reflected dinosaur. */ - drawDinosaur(); - - /* Disable noramlize again and re-enable back face culling. */ - glDisable(GL_NORMALIZE); - glCullFace(GL_BACK); - - glPopMatrix(); - - /* Switch back to the unreflected light position. */ - glLightfv(GL_LIGHT0, GL_POSITION, lightPosition); - - if (stencilReflection) { - glDisable(GL_STENCIL_TEST); - } - } - - /* Back face culling will get used to only draw either the top or the - bottom floor. This let's us get a floor with two distinct - appearances. The top floor surface is reflective and kind of red. - The bottom floor surface is not reflective and blue. */ - - /* Draw "bottom" of floor in blue. */ - glFrontFace(GL_CW); /* Switch face orientation. */ - glColor4f(0.1, 0.1, 0.7, 1.0); - drawFloor(); - glFrontFace(GL_CCW); - - if (renderShadow) { - if (stencilShadow) { - /* Draw the floor with stencil value 3. This helps us only - draw the shadow once per floor pixel (and only on the - floor pixels). */ - glEnable(GL_STENCIL_TEST); - glStencilFunc(GL_ALWAYS, 3, 0xffffffff); - glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE); - } - } - - /* Draw "top" of floor. Use blending to blend in reflection. */ - glEnable(GL_BLEND); - glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); - glColor4f(0.7, 0.0, 0.0, 0.3); - glColor4f(1.0, 1.0, 1.0, 0.3); - drawFloor(); - glDisable(GL_BLEND); - - if (renderDinosaur) { - /* Draw "actual" dinosaur, not its reflection. */ - drawDinosaur(); - } - - if (renderShadow) { - - /* Render the projected shadow. */ - - if (stencilShadow) { - - /* Now, only render where stencil is set above 2 (ie, 3 where - the top floor is). Update stencil with 2 where the shadow - gets drawn so we don't redraw (and accidently reblend) the - shadow). */ - glStencilFunc(GL_LESS, 2, 0xffffffff); /* draw if ==1 */ - glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE); - } - - /* To eliminate depth buffer artifacts, we use polygon offset - to raise the depth of the projected shadow slightly so - that it does not depth buffer alias with the floor. */ - if (offsetShadow) { - switch (polygonOffsetVersion) { - case EXTENSION: -#ifdef GL_EXT_polygon_offset - glEnable(GL_POLYGON_OFFSET_EXT); - break; -#endif -#ifdef GL_VERSION_1_1 - case ONE_DOT_ONE: - glEnable(GL_POLYGON_OFFSET_FILL); - break; -#endif - case MISSING: - /* Oh well. */ - break; - } - } - - /* Render 50% black shadow color on top of whatever the - floor appareance is. */ - glEnable(GL_BLEND); - glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); - glDisable(GL_LIGHTING); /* Force the 50% black. */ - glColor4f(0.0, 0.0, 0.0, 0.5); - - glPushMatrix(); - /* Project the shadow. */ - glMultMatrixf((GLfloat *) floorShadow); - drawDinosaur(); - glPopMatrix(); - - glDisable(GL_BLEND); - glEnable(GL_LIGHTING); - - if (offsetShadow) { - switch (polygonOffsetVersion) { -#ifdef GL_EXT_polygon_offset - case EXTENSION: - glDisable(GL_POLYGON_OFFSET_EXT); - break; -#endif -#ifdef GL_VERSION_1_1 - case ONE_DOT_ONE: - glDisable(GL_POLYGON_OFFSET_FILL); - break; -#endif - case MISSING: - /* Oh well. */ - break; - } - } - if (stencilShadow) { - glDisable(GL_STENCIL_TEST); - } - } - - glPushMatrix(); - glDisable(GL_LIGHTING); - glColor3f(1.0, 1.0, 0.0); - if (directionalLight) { - /* Draw an arrowhead. */ - glDisable(GL_CULL_FACE); - glTranslatef(lightPosition[0], lightPosition[1], lightPosition[2]); - glRotatef(lightAngle * -180.0 / M_PI, 0, 1, 0); - glRotatef(atan(lightHeight/12) * 180.0 / M_PI, 0, 0, 1); - glBegin(GL_TRIANGLE_FAN); - glVertex3f(0, 0, 0); - glVertex3f(2, 1, 1); - glVertex3f(2, -1, 1); - glVertex3f(2, -1, -1); - glVertex3f(2, 1, -1); - glVertex3f(2, 1, 1); - glEnd(); - /* Draw a white line from light direction. */ - glColor3f(1.0, 1.0, 1.0); - glBegin(GL_LINES); - glVertex3f(0, 0, 0); - glVertex3f(5, 0, 0); - glEnd(); - glEnable(GL_CULL_FACE); - } else { - /* Draw a yellow ball at the light source. */ - glTranslatef(lightPosition[0], lightPosition[1], lightPosition[2]); - glutSolidSphere(1.0, 5, 5); - } - glEnable(GL_LIGHTING); - glPopMatrix(); - - glPopMatrix(); - - if (reportSpeed) { - glFinish(); - end = glutGet(GLUT_ELAPSED_TIME); - printf("Speed %.3g frames/sec (%d ms)\n", 1000.0/(end-start), end-start); - } - - glutSwapBuffers(); -} - -/* ARGSUSED2 */ -static void -mouse(int button, int state, int x, int y) -{ - if (button == GLUT_LEFT_BUTTON) { - if (state == GLUT_DOWN) { - moving = 1; - startx = x; - starty = y; - } - if (state == GLUT_UP) { - moving = 0; - } - } - if (button == GLUT_MIDDLE_BUTTON) { - if (state == GLUT_DOWN) { - lightMoving = 1; - lightStartX = x; - lightStartY = y; - } - if (state == GLUT_UP) { - lightMoving = 0; - } - } -} - -/* ARGSUSED1 */ -static void -motion(int x, int y) -{ - if (moving) { - angle = angle + (x - startx); - angle2 = angle2 + (y - starty); - startx = x; - starty = y; - glutPostRedisplay(); - } - if (lightMoving) { - lightAngle += (x - lightStartX)/40.0; - lightHeight += (lightStartY - y)/20.0; - lightStartX = x; - lightStartY = y; - glutPostRedisplay(); - } -} - -/* Advance time varying state when idle callback registered. */ -static void -idle(void) -{ - static float time = 0.0; - - time = glutGet(GLUT_ELAPSED_TIME) / 500.0; - - jump = 4.0 * fabs(sin(time)*0.5); - if (!lightMoving) { - lightAngle += 0.03; - } - glutPostRedisplay(); -} - -enum { - M_NONE, M_MOTION, M_LIGHT, M_TEXTURE, M_SHADOWS, M_REFLECTION, M_DINOSAUR, - M_STENCIL_REFLECTION, M_STENCIL_SHADOW, M_OFFSET_SHADOW, - M_POSITIONAL, M_DIRECTIONAL, M_PERFORMANCE -}; - -static void -controlLights(int value) -{ - switch (value) { - case M_NONE: - return; - case M_MOTION: - animation = 1 - animation; - if (animation) { - glutIdleFunc(idle); - } else { - glutIdleFunc(NULL); - } - break; - case M_LIGHT: - lightSwitch = !lightSwitch; - if (lightSwitch) { - glEnable(GL_LIGHT0); - } else { - glDisable(GL_LIGHT0); - } - break; - case M_TEXTURE: - useTexture = !useTexture; - break; - case M_SHADOWS: - renderShadow = 1 - renderShadow; - break; - case M_REFLECTION: - renderReflection = 1 - renderReflection; - break; - case M_DINOSAUR: - renderDinosaur = 1 - renderDinosaur; - break; - case M_STENCIL_REFLECTION: - stencilReflection = 1 - stencilReflection; - break; - case M_STENCIL_SHADOW: - stencilShadow = 1 - stencilShadow; - break; - case M_OFFSET_SHADOW: - offsetShadow = 1 - offsetShadow; - break; - case M_POSITIONAL: - directionalLight = 0; - break; - case M_DIRECTIONAL: - directionalLight = 1; - break; - case M_PERFORMANCE: - reportSpeed = 1 - reportSpeed; - break; - } - glutPostRedisplay(); -} - -/* When not visible, stop animating. Restart when visible again. */ -static void -visible(int vis) -{ - if (vis == GLUT_VISIBLE) { - if (animation) - glutIdleFunc(idle); - } else { - if (!animation) - glutIdleFunc(NULL); - } -} - -/* Press any key to redraw; good when motion stopped and - performance reporting on. */ -/* ARGSUSED */ -static void -key(unsigned char c, int x, int y) -{ - if (c == 27) { - exit(0); /* IRIS GLism, Escape quits. */ - } - glutPostRedisplay(); -} - -/* Press any key to redraw; good when motion stopped and - performance reporting on. */ -/* ARGSUSED */ -static void -special(int k, int x, int y) -{ - glutPostRedisplay(); -} - -static int -supportsOneDotOne(void) -{ - const char *version; - int major, minor; - - version = (char *) glGetString(GL_VERSION); - if (sscanf(version, "%d.%d", &major, &minor) == 2) - return major >= 1 && minor >= 1; - return 0; /* OpenGL version string malformed! */ -} - -int -main(int argc, char **argv) -{ - int i; - - glutInit(&argc, argv); - - for (i=1; i<argc; i++) { - if (!strcmp("-linear", argv[i])) { - linearFiltering = 1; - } else if (!strcmp("-mipmap", argv[i])) { - useMipmaps = 1; - } else if (!strcmp("-ext", argv[i])) { - forceExtension = 1; - } - } - - glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL); - -#if 0 - /* In GLUT 4.0, you'll be able to do this an be sure to - get 2 bits of stencil if the machine has it for you. */ - glutInitDisplayString("samples stencil>=2 rgb double depth"); -#endif - - glutCreateWindow("Shadowy Leapin' Lizards"); - - if (glutGet(GLUT_WINDOW_STENCIL_SIZE) <= 1) { - printf("dinoshade: Sorry, I need at least 2 bits of stencil.\n"); - exit(1); - } - - /* Register GLUT callbacks. */ - glutDisplayFunc(redraw); - glutMouseFunc(mouse); - glutMotionFunc(motion); - glutVisibilityFunc(visible); - glutKeyboardFunc(key); - glutSpecialFunc(special); - - glutCreateMenu(controlLights); - - glutAddMenuEntry("Toggle motion", M_MOTION); - glutAddMenuEntry("-----------------------", M_NONE); - glutAddMenuEntry("Toggle light", M_LIGHT); - glutAddMenuEntry("Toggle texture", M_TEXTURE); - glutAddMenuEntry("Toggle shadows", M_SHADOWS); - glutAddMenuEntry("Toggle reflection", M_REFLECTION); - glutAddMenuEntry("Toggle dinosaur", M_DINOSAUR); - glutAddMenuEntry("-----------------------", M_NONE); - glutAddMenuEntry("Toggle reflection stenciling", M_STENCIL_REFLECTION); - glutAddMenuEntry("Toggle shadow stenciling", M_STENCIL_SHADOW); - glutAddMenuEntry("Toggle shadow offset", M_OFFSET_SHADOW); - glutAddMenuEntry("----------------------", M_NONE); - glutAddMenuEntry("Positional light", M_POSITIONAL); - glutAddMenuEntry("Directional light", M_DIRECTIONAL); - glutAddMenuEntry("-----------------------", M_NONE); - glutAddMenuEntry("Toggle performance", M_PERFORMANCE); - glutAttachMenu(GLUT_RIGHT_BUTTON); - makeDinosaur(); - -#ifdef GL_VERSION_1_1 - if (supportsOneDotOne() && !forceExtension) { - polygonOffsetVersion = ONE_DOT_ONE; - glPolygonOffset(-2.0, -9.0); - } else -#endif - { -#ifdef GL_EXT_polygon_offset - /* check for the polygon offset extension */ - if (glutExtensionSupported("GL_EXT_polygon_offset")) { - polygonOffsetVersion = EXTENSION; - glPolygonOffsetEXT(-2.0, -0.002); - } else -#endif - { - polygonOffsetVersion = MISSING; - printf("\ndinoshine: Missing polygon offset.\n"); - printf(" Expect shadow depth aliasing artifacts.\n\n"); - } - } - - glEnable(GL_CULL_FACE); - glEnable(GL_DEPTH_TEST); - glEnable(GL_TEXTURE_2D); - glLineWidth(3.0); - - glMatrixMode(GL_PROJECTION); - gluPerspective( /* field of view in degree */ 40.0, - /* aspect ratio */ 1.0, - /* Z near */ 20.0, /* Z far */ 100.0); - glMatrixMode(GL_MODELVIEW); - gluLookAt(0.0, 8.0, 60.0, /* eye is at (0,8,60) */ - 0.0, 8.0, 0.0, /* center is at (0,8,0) */ - 0.0, 1.0, 0.); /* up is in postivie Y direction */ - - glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, 1); - glLightfv(GL_LIGHT0, GL_DIFFUSE, lightColor); - glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 0.1); - glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 0.05); - glEnable(GL_LIGHT0); - glEnable(GL_LIGHTING); - - makeFloorTexture(); - - /* Setup floor plane for projected shadow calculations. */ - findPlane(floorPlane, floorVertices[1], floorVertices[2], floorVertices[3]); - - glutMainLoop(); - return 0; /* ANSI C requires main to return int. */ -} |