--- /dev/null
+
+/* projtex.c - by David Yu and David Blythe, SGI */
+
+/**
+ ** Demonstrates simple projective texture mapping.
+ **
+ ** Button1 changes view, Button2 moves texture.
+ **
+ ** (See: Segal, Korobkin, van Widenfelt, Foran, and Haeberli
+ ** "Fast Shadows and Lighting Effects Using Texture Mapping", SIGGRAPH '92)
+ **
+ ** 1994,1995 -- David G Yu
+ **
+ ** cc -o projtex projtex.c texture.c -lglut -lGLU -lGL -lX11 -lm
+ **/
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <GL/glew.h>
+#include <GL/glut.h>
+#include "readtex.h"
+
+
+/* Some <math.h> files do not define M_PI... */
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+#define MAX_TEX 4
+int NumTextures = 1;
+
+int winWidth, winHeight;
+
+GLboolean redrawContinuously = GL_FALSE;
+
+float angle, axis[3];
+enum MoveModes {
+ MoveNone, MoveView, MoveObject, MoveTexture
+};
+enum MoveModes mode = MoveNone;
+
+GLfloat objectXform[4][4];
+GLfloat textureXform[MAX_TEX][4][4];
+
+void (*drawObject) (void);
+void (*loadTexture) (void);
+GLboolean textureEnabled = GL_TRUE;
+GLboolean showProjection = GL_TRUE;
+GLboolean linearFilter = GL_TRUE;
+
+char *texFilename[MAX_TEX] = {
+ "../images/girl.rgb",
+ "../images/tile.rgb",
+ "../images/bw.rgb",
+ "../images/reflect.rgb"
+};
+
+
+GLfloat zoomFactor = 1.0;
+
+/*****************************************************************/
+
+
+static void
+ActiveTexture(int i)
+{
+ glActiveTextureARB(i);
+}
+
+
+/* matrix = identity */
+static void
+matrixIdentity(GLfloat matrix[16])
+{
+ matrix[0] = 1.0;
+ matrix[1] = 0.0;
+ matrix[2] = 0.0;
+ matrix[3] = 0.0;
+ matrix[4] = 0.0;
+ matrix[5] = 1.0;
+ matrix[6] = 0.0;
+ matrix[7] = 0.0;
+ matrix[8] = 0.0;
+ matrix[9] = 0.0;
+ matrix[10] = 1.0;
+ matrix[11] = 0.0;
+ matrix[12] = 0.0;
+ matrix[13] = 0.0;
+ matrix[14] = 0.0;
+ matrix[15] = 1.0;
+}
+
+/* matrix2 = transpose(matrix1) */
+static void
+matrixTranspose(GLfloat matrix2[16], GLfloat matrix1[16])
+{
+ matrix2[0] = matrix1[0];
+ matrix2[1] = matrix1[4];
+ matrix2[2] = matrix1[8];
+ matrix2[3] = matrix1[12];
+
+ matrix2[4] = matrix1[1];
+ matrix2[5] = matrix1[5];
+ matrix2[6] = matrix1[9];
+ matrix2[7] = matrix1[13];
+
+ matrix2[8] = matrix1[2];
+ matrix2[9] = matrix1[6];
+ matrix2[10] = matrix1[10];
+ matrix2[11] = matrix1[14];
+
+ matrix2[12] = matrix1[3];
+ matrix2[13] = matrix1[7];
+ matrix2[14] = matrix1[14];
+ matrix2[15] = matrix1[15];
+}
+
+/*****************************************************************/
+
+/* load SGI .rgb image (pad with a border of the specified width and color) */
+#if 0
+static void
+imgLoad(char *filenameIn, int borderIn, GLfloat borderColorIn[4],
+ int *wOut, int *hOut, GLubyte ** imgOut)
+{
+ int border = borderIn;
+ int width, height;
+ int w, h;
+ GLubyte *image, *img, *p;
+ int i, j, components;
+
+ image = (GLubyte *) read_texture(filenameIn, &width, &height, &components);
+ w = width + 2 * border;
+ h = height + 2 * border;
+ img = (GLubyte *) calloc(w * h, 4 * sizeof(unsigned char));
+
+ p = img;
+ for (j = -border; j < height + border; ++j) {
+ for (i = -border; i < width + border; ++i) {
+ if (0 <= j && j <= height - 1 && 0 <= i && i <= width - 1) {
+ p[0] = image[4 * (j * width + i) + 0];
+ p[1] = image[4 * (j * width + i) + 1];
+ p[2] = image[4 * (j * width + i) + 2];
+ p[3] = 0xff;
+ } else {
+ p[0] = borderColorIn[0] * 0xff;
+ p[1] = borderColorIn[1] * 0xff;
+ p[2] = borderColorIn[2] * 0xff;
+ p[3] = borderColorIn[3] * 0xff;
+ }
+ p += 4;
+ }
+ }
+ free(image);
+ *wOut = w;
+ *hOut = h;
+ *imgOut = img;
+}
+#endif
+
+
+/*****************************************************************/
+
+/* Load the image file specified on the command line as the current texture */
+static void
+loadImageTextures(void)
+{
+ GLfloat borderColor[4] =
+ {1.0, 1.0, 1.0, 1.0};
+ int tex;
+
+ for (tex = 0; tex < NumTextures; tex++) {
+ GLubyte *image, *texData3, *texData4;
+ GLint imgWidth, imgHeight;
+ GLenum imgFormat;
+ int i, j;
+
+ printf("loading %s\n", texFilename[tex]);
+ image = LoadRGBImage(texFilename[tex], &imgWidth, &imgHeight, &imgFormat);
+ if (!image) {
+ printf("can't find %s\n", texFilename[tex]);
+ exit(1);
+ }
+ assert(imgFormat == GL_RGB);
+
+ /* scale to 256x256 */
+ texData3 = malloc(256 * 256 * 4);
+ texData4 = malloc(256 * 256 * 4);
+ assert(texData3);
+ assert(texData4);
+ gluScaleImage(imgFormat, imgWidth, imgHeight, GL_UNSIGNED_BYTE, image,
+ 256, 256, GL_UNSIGNED_BYTE, texData3);
+
+ /* convert to rgba */
+ for (i = 0; i < 256 * 256; i++) {
+ texData4[i*4+0] = texData3[i*3+0];
+ texData4[i*4+1] = texData3[i*3+1];
+ texData4[i*4+2] = texData3[i*3+2];
+ texData4[i*4+3] = 128;
+ }
+
+ /* put transparent border around image */
+ for (i = 0; i < 256; i++) {
+ texData4[i*4+0] = 255;
+ texData4[i*4+1] = 255;
+ texData4[i*4+2] = 255;
+ texData4[i*4+3] = 0;
+ }
+ j = 256 * 255 * 4;
+ for (i = 0; i < 256; i++) {
+ texData4[j + i*4+0] = 255;
+ texData4[j + i*4+1] = 255;
+ texData4[j + i*4+2] = 255;
+ texData4[j + i*4+3] = 0;
+ }
+ for (i = 0; i < 256; i++) {
+ j = i * 256 * 4;
+ texData4[j+0] = 255;
+ texData4[j+1] = 255;
+ texData4[j+2] = 255;
+ texData4[j+3] = 0;
+ }
+ for (i = 0; i < 256; i++) {
+ j = i * 256 * 4 + 255 * 4;
+ texData4[j+0] = 255;
+ texData4[j+1] = 255;
+ texData4[j+2] = 255;
+ texData4[j+3] = 0;
+ }
+
+ ActiveTexture(GL_TEXTURE0_ARB + tex);
+ glBindTexture(GL_TEXTURE_2D, tex + 1);
+
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0,
+ GL_RGBA, GL_UNSIGNED_BYTE, texData4);
+
+ 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);
+ }
+ glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
+ }
+}
+
+/* Create a simple spotlight pattern and make it the current texture */
+static void
+loadSpotlightTexture(void)
+{
+ static int texWidth = 64, texHeight = 64;
+ static GLubyte *texData;
+ GLfloat borderColor[4] =
+ {0.1, 0.1, 0.1, 1.0};
+
+ if (!texData) {
+ GLubyte *p;
+ int i, j;
+
+ texData = (GLubyte *) malloc(texWidth * texHeight * 4 * sizeof(GLubyte));
+
+ p = texData;
+ for (j = 0; j < texHeight; ++j) {
+ float dy = (texHeight * 0.5 - j + 0.5) / (texHeight * 0.5);
+
+ for (i = 0; i < texWidth; ++i) {
+ float dx = (texWidth * 0.5 - i + 0.5) / (texWidth * 0.5);
+ float r = cos(M_PI / 2.0 * sqrt(dx * dx + dy * dy));
+ float c;
+
+ r = (r < 0) ? 0 : r * r;
+ c = 0xff * (r + borderColor[0]);
+ p[0] = (c <= 0xff) ? c : 0xff;
+ c = 0xff * (r + borderColor[1]);
+ p[1] = (c <= 0xff) ? c : 0xff;
+ c = 0xff * (r + borderColor[2]);
+ p[2] = (c <= 0xff) ? c : 0xff;
+ c = 0xff * (r + borderColor[3]);
+ p[3] = (c <= 0xff) ? c : 0xff;
+ p += 4;
+ }
+ }
+ }
+ 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);
+ }
+ glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
+ gluBuild2DMipmaps(GL_TEXTURE_2D, 4, texWidth, texHeight,
+ GL_RGBA, GL_UNSIGNED_BYTE, texData);
+}
+
+/*****************************************************************/
+
+static void
+checkErrors(void)
+{
+ GLenum error;
+ while ((error = glGetError()) != GL_NO_ERROR) {
+ fprintf(stderr, "Error: %s\n", (char *) gluErrorString(error));
+ }
+}
+
+static void
+drawCube(void)
+{
+ glBegin(GL_QUADS);
+
+ glNormal3f(-1.0, 0.0, 0.0);
+ glColor3f(0.80, 0.50, 0.50);
+ glVertex3f(-0.5, -0.5, -0.5);
+ glVertex3f(-0.5, -0.5, 0.5);
+ glVertex3f(-0.5, 0.5, 0.5);
+ glVertex3f(-0.5, 0.5, -0.5);
+
+ glNormal3f(1.0, 0.0, 0.0);
+ glColor3f(0.50, 0.80, 0.50);
+ glVertex3f(0.5, 0.5, 0.5);
+ glVertex3f(0.5, -0.5, 0.5);
+ glVertex3f(0.5, -0.5, -0.5);
+ glVertex3f(0.5, 0.5, -0.5);
+
+ glNormal3f(0.0, -1.0, 0.0);
+ glColor3f(0.50, 0.50, 0.80);
+ glVertex3f(-0.5, -0.5, -0.5);
+ glVertex3f(0.5, -0.5, -0.5);
+ glVertex3f(0.5, -0.5, 0.5);
+ glVertex3f(-0.5, -0.5, 0.5);
+
+ glNormal3f(0.0, 1.0, 0.0);
+ glColor3f(0.50, 0.80, 0.80);
+ glVertex3f(0.5, 0.5, 0.5);
+ glVertex3f(0.5, 0.5, -0.5);
+ glVertex3f(-0.5, 0.5, -0.5);
+ glVertex3f(-0.5, 0.5, 0.5);
+
+ glNormal3f(0.0, 0.0, -1.0);
+ glColor3f(0.80, 0.50, 0.80);
+ glVertex3f(-0.5, -0.5, -0.5);
+ glVertex3f(-0.5, 0.5, -0.5);
+ glVertex3f(0.5, 0.5, -0.5);
+ glVertex3f(0.5, -0.5, -0.5);
+
+ glNormal3f(0.0, 0.0, 1.0);
+ glColor3f(1.00, 0.80, 0.50);
+ glVertex3f(0.5, 0.5, 0.5);
+ glVertex3f(-0.5, 0.5, 0.5);
+ glVertex3f(-0.5, -0.5, 0.5);
+ glVertex3f(0.5, -0.5, 0.5);
+ glEnd();
+}
+
+static void
+drawDodecahedron(void)
+{
+#define A (0.5 * 1.61803) /* (sqrt(5) + 1) / 2 */
+#define B (0.5 * 0.61803) /* (sqrt(5) - 1) / 2 */
+#define C (0.5 * 1.0)
+ GLfloat vertexes[20][3] =
+ {
+ {-A, 0.0, B},
+ {-A, 0.0, -B},
+ {A, 0.0, -B},
+ {A, 0.0, B},
+ {B, -A, 0.0},
+ {-B, -A, 0.0},
+ {-B, A, 0.0},
+ {B, A, 0.0},
+ {0.0, B, -A},
+ {0.0, -B, -A},
+ {0.0, -B, A},
+ {0.0, B, A},
+ {-C, -C, C},
+ {-C, -C, -C},
+ {C, -C, -C},
+ {C, -C, C},
+ {-C, C, C},
+ {-C, C, -C},
+ {C, C, -C},
+ {C, C, C},
+ };
+#undef A
+#undef B
+#undef C
+ GLint polygons[12][5] =
+ {
+ {0, 12, 10, 11, 16},
+ {1, 17, 8, 9, 13},
+ {2, 14, 9, 8, 18},
+ {3, 19, 11, 10, 15},
+ {4, 14, 2, 3, 15},
+ {5, 12, 0, 1, 13},
+ {6, 17, 1, 0, 16},
+ {7, 19, 3, 2, 18},
+ {8, 17, 6, 7, 18},
+ {9, 14, 4, 5, 13},
+ {10, 12, 5, 4, 15},
+ {11, 19, 7, 6, 16},
+ };
+ int i;
+
+ glColor3f(0.75, 0.75, 0.75);
+ for (i = 0; i < 12; ++i) {
+ GLfloat *p0, *p1, *p2, d;
+ GLfloat u[3], v[3], n[3];
+
+ p0 = &vertexes[polygons[i][0]][0];
+ p1 = &vertexes[polygons[i][1]][0];
+ p2 = &vertexes[polygons[i][2]][0];
+
+ u[0] = p2[0] - p1[0];
+ u[1] = p2[1] - p1[1];
+ u[2] = p2[2] - p1[2];
+
+ v[0] = p0[0] - p1[0];
+ v[1] = p0[1] - p1[1];
+ v[2] = p0[2] - p1[2];
+
+ n[0] = u[1] * v[2] - u[2] * v[1];
+ n[1] = u[2] * v[0] - u[0] * v[2];
+ n[2] = u[0] * v[1] - u[1] * v[0];
+
+ d = 1.0 / sqrt(n[0] * n[0] + n[1] * n[1] + n[2] * n[2]);
+ n[0] *= d;
+ n[1] *= d;
+ n[2] *= d;
+
+ glBegin(GL_POLYGON);
+ glNormal3fv(n);
+ glVertex3fv(p0);
+ glVertex3fv(p1);
+ glVertex3fv(p2);
+ glVertex3fv(vertexes[polygons[i][3]]);
+ glVertex3fv(vertexes[polygons[i][4]]);
+ glEnd();
+ }
+}
+
+static void
+drawSphere(void)
+{
+ int numMajor = 24;
+ int numMinor = 32;
+ float radius = 0.8;
+ double majorStep = (M_PI / numMajor);
+ double minorStep = (2.0 * M_PI / numMinor);
+ int i, j;
+
+ glColor3f(0.50, 0.50, 0.50);
+ for (i = 0; i < numMajor; ++i) {
+ double a = i * majorStep;
+ double b = a + majorStep;
+ double r0 = radius * sin(a);
+ double r1 = radius * sin(b);
+ GLfloat z0 = radius * cos(a);
+ GLfloat z1 = radius * cos(b);
+
+ glBegin(GL_TRIANGLE_STRIP);
+ for (j = 0; j <= numMinor; ++j) {
+ double c = j * minorStep;
+ GLfloat x = cos(c);
+ GLfloat y = sin(c);
+
+ glNormal3f((x * r0) / radius, (y * r0) / radius, z0 / radius);
+ glTexCoord2f(j / (GLfloat) numMinor, i / (GLfloat) numMajor);
+ glVertex3f(x * r0, y * r0, z0);
+
+ glNormal3f((x * r1) / radius, (y * r1) / radius, z1 / radius);
+ glTexCoord2f(j / (GLfloat) numMinor, (i + 1) / (GLfloat) numMajor);
+ glVertex3f(x * r1, y * r1, z1);
+ }
+ glEnd();
+ }
+}
+
+/*****************************************************************/
+
+float xmin = -0.035, xmax = 0.035;
+float ymin = -0.035, ymax = 0.035;
+float nnear = 0.1;
+float ffar = 1.9;
+float distance = -1.0;
+
+static void
+loadTextureProjection(int texUnit, GLfloat m[16])
+{
+ GLfloat mInverse[4][4];
+
+ /* Should use true inverse, but since m consists only of rotations, we can
+ just use the transpose. */
+ matrixTranspose((GLfloat *) mInverse, m);
+
+ ActiveTexture(GL_TEXTURE0_ARB + texUnit);
+ glMatrixMode(GL_TEXTURE);
+ glLoadIdentity();
+ glTranslatef(0.5, 0.5, 0.0);
+ glScalef(0.5, 0.5, 1.0);
+ glFrustum(xmin, xmax, ymin, ymax, nnear, ffar);
+ glTranslatef(0.0, 0.0, distance);
+ glMultMatrixf((GLfloat *) mInverse);
+ glMatrixMode(GL_MODELVIEW);
+}
+
+static void
+drawTextureProjection(void)
+{
+ float t = ffar / nnear;
+ GLfloat n[4][3];
+ GLfloat f[4][3];
+
+ n[0][0] = xmin;
+ n[0][1] = ymin;
+ n[0][2] = -(nnear + distance);
+
+ n[1][0] = xmax;
+ n[1][1] = ymin;
+ n[1][2] = -(nnear + distance);
+
+ n[2][0] = xmax;
+ n[2][1] = ymax;
+ n[2][2] = -(nnear + distance);
+
+ n[3][0] = xmin;
+ n[3][1] = ymax;
+ n[3][2] = -(nnear + distance);
+
+ f[0][0] = xmin * t;
+ f[0][1] = ymin * t;
+ f[0][2] = -(ffar + distance);
+
+ f[1][0] = xmax * t;
+ f[1][1] = ymin * t;
+ f[1][2] = -(ffar + distance);
+
+ f[2][0] = xmax * t;
+ f[2][1] = ymax * t;
+ f[2][2] = -(ffar + distance);
+
+ f[3][0] = xmin * t;
+ f[3][1] = ymax * t;
+ f[3][2] = -(ffar + distance);
+
+ glColor3f(1.0, 1.0, 0.0);
+ glBegin(GL_LINE_LOOP);
+ glVertex3fv(n[0]);
+ glVertex3fv(n[1]);
+ glVertex3fv(n[2]);
+ glVertex3fv(n[3]);
+ glVertex3fv(f[3]);
+ glVertex3fv(f[2]);
+ glVertex3fv(f[1]);
+ glVertex3fv(f[0]);
+ glVertex3fv(n[0]);
+ glVertex3fv(n[1]);
+ glVertex3fv(f[1]);
+ glVertex3fv(f[0]);
+ glVertex3fv(f[3]);
+ glVertex3fv(f[2]);
+ glVertex3fv(n[2]);
+ glVertex3fv(n[3]);
+ glEnd();
+}
+
+/*****************************************************************/
+
+static void
+initialize(void)
+{
+ GLfloat light0Pos[4] =
+ {0.3, 0.3, 0.0, 1.0};
+ GLfloat matAmb[4] =
+ {0.01, 0.01, 0.01, 1.00};
+ GLfloat matDiff[4] =
+ {0.65, 0.65, 0.65, 1.00};
+ GLfloat matSpec[4] =
+ {0.30, 0.30, 0.30, 1.00};
+ GLfloat matShine = 10.0;
+ GLfloat eyePlaneS[] =
+ {1.0, 0.0, 0.0, 0.0};
+ GLfloat eyePlaneT[] =
+ {0.0, 1.0, 0.0, 0.0};
+ GLfloat eyePlaneR[] =
+ {0.0, 0.0, 1.0, 0.0};
+ GLfloat eyePlaneQ[] =
+ {0.0, 0.0, 0.0, 1.0};
+ int i;
+
+ /* Setup Misc. */
+ glClearColor(0.41, 0.41, 0.31, 0.0);
+
+ glEnable(GL_DEPTH_TEST);
+
+ /* glLineWidth(2.0);*/
+
+ glCullFace(GL_FRONT);
+ glEnable(GL_CULL_FACE);
+
+ glMatrixMode(GL_PROJECTION);
+ glFrustum(-0.5, 0.5, -0.5, 0.5, 1, 3);
+ glMatrixMode(GL_MODELVIEW);
+ glTranslatef(0, 0, -2);
+
+ matrixIdentity((GLfloat *) objectXform);
+ for (i = 0; i < NumTextures; i++) {
+ matrixIdentity((GLfloat *) textureXform[i]);
+ }
+
+ glMatrixMode(GL_PROJECTION);
+ glPushMatrix();
+ glLoadIdentity();
+ glOrtho(0, 1, 0, 1, -1, 1);
+ glMatrixMode(GL_MODELVIEW);
+ glPushMatrix();
+ glLoadIdentity();
+
+ glRasterPos2i(0, 0);
+
+ glPopMatrix();
+ glMatrixMode(GL_PROJECTION);
+ glPopMatrix();
+ glMatrixMode(GL_MODELVIEW);
+
+ /* Setup Lighting */
+ glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, matAmb);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, matDiff);
+ glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, matSpec);
+ glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, matShine);
+
+ glEnable(GL_COLOR_MATERIAL);
+
+ glLightfv(GL_LIGHT0, GL_POSITION, light0Pos);
+ glEnable(GL_LIGHT0);
+
+ glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
+ glEnable(GL_LIGHTING);
+
+ /* Setup Texture */
+
+ (*loadTexture) ();
+
+
+ for (i = 0; i < NumTextures; i++) {
+ ActiveTexture(GL_TEXTURE0_ARB + i);
+
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+ glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+
+ glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
+ glTexGenfv(GL_S, GL_EYE_PLANE, eyePlaneS);
+
+ glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
+ glTexGenfv(GL_T, GL_EYE_PLANE, eyePlaneT);
+
+ glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
+ glTexGenfv(GL_R, GL_EYE_PLANE, eyePlaneR);
+
+ glTexGeni(GL_Q, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
+ glTexGenfv(GL_Q, GL_EYE_PLANE, eyePlaneQ);
+ }
+}
+
+static void
+display(void)
+{
+ int i;
+
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ if (textureEnabled) {
+ if (mode == MoveTexture || mode == MoveView) {
+ /* Have OpenGL compute the new transformation (simple but slow). */
+ for (i = 0; i < NumTextures; i++) {
+ glPushMatrix();
+ glLoadIdentity();
+#if 0
+ if (i & 1)
+ glRotatef(angle, axis[0], axis[1], axis[2]);
+ else
+#endif
+ glRotatef(angle*(i+1), axis[0], axis[1], axis[2]);
+
+ glMultMatrixf((GLfloat *) textureXform[i]);
+ glGetFloatv(GL_MODELVIEW_MATRIX, (GLfloat *) textureXform[i]);
+ glPopMatrix();
+ }
+ }
+ for (i = 0; i < NumTextures; i++) {
+ loadTextureProjection(i, (GLfloat *) textureXform[i]);
+ }
+
+ if (showProjection) {
+ for (i = 0; i < NumTextures; i++) {
+ ActiveTexture(GL_TEXTURE0_ARB + i);
+ glPushMatrix();
+ glMultMatrixf((GLfloat *) textureXform[i]);
+ glDisable(GL_LIGHTING);
+ drawTextureProjection();
+ glEnable(GL_LIGHTING);
+ glPopMatrix();
+ }
+ }
+ for (i = 0; i < NumTextures; i++) {
+ ActiveTexture(GL_TEXTURE0_ARB + i);
+ glEnable(GL_TEXTURE_2D);
+ glEnable(GL_TEXTURE_GEN_S);
+ glEnable(GL_TEXTURE_GEN_T);
+ glEnable(GL_TEXTURE_GEN_R);
+ glEnable(GL_TEXTURE_GEN_Q);
+ }
+ }
+ if (mode == MoveObject || mode == MoveView) {
+ /* Have OpenGL compute the new transformation (simple but slow). */
+ glPushMatrix();
+ glLoadIdentity();
+ glRotatef(angle, axis[0], axis[1], axis[2]);
+ glMultMatrixf((GLfloat *) objectXform);
+ glGetFloatv(GL_MODELVIEW_MATRIX, (GLfloat *) objectXform);
+ glPopMatrix();
+ }
+ glPushMatrix();
+ glMultMatrixf((GLfloat *) objectXform);
+ (*drawObject) ();
+ glPopMatrix();
+
+ for (i = 0; i < NumTextures; i++) {
+ ActiveTexture(GL_TEXTURE0_ARB + i);
+ glDisable(GL_TEXTURE_2D);
+ glDisable(GL_TEXTURE_GEN_S);
+ glDisable(GL_TEXTURE_GEN_T);
+ glDisable(GL_TEXTURE_GEN_R);
+ glDisable(GL_TEXTURE_GEN_Q);
+ }
+
+ if (zoomFactor > 1.0) {
+ glDisable(GL_DEPTH_TEST);
+ glCopyPixels(0, 0, winWidth / zoomFactor, winHeight / zoomFactor, GL_COLOR);
+ glEnable(GL_DEPTH_TEST);
+ }
+ glFlush();
+ glutSwapBuffers();
+ checkErrors();
+}
+
+/*****************************************************************/
+
+/* simple trackball-like motion control */
+static float lastPos[3];
+static int lastTime;
+
+static void
+ptov(int x, int y, int width, int height, float v[3])
+{
+ float d, a;
+
+ /* project x,y onto a hemi-sphere centered within width, height */
+ v[0] = (2.0 * x - width) / width;
+ v[1] = (height - 2.0 * y) / height;
+ d = sqrt(v[0] * v[0] + v[1] * v[1]);
+ v[2] = cos((M_PI / 2.0) * ((d < 1.0) ? d : 1.0));
+ a = 1.0 / sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
+ v[0] *= a;
+ v[1] *= a;
+ v[2] *= a;
+}
+
+static void
+startMotion(int x, int y, int but, int time)
+{
+ if (but == GLUT_LEFT_BUTTON) {
+ mode = MoveView;
+ } else if (but == GLUT_MIDDLE_BUTTON) {
+ mode = MoveTexture;
+ } else {
+ return;
+ }
+
+ lastTime = time;
+ ptov(x, y, winWidth, winHeight, lastPos);
+}
+
+static void
+animate(void)
+{
+ glutPostRedisplay();
+}
+
+static void
+vis(int visible)
+{
+ if (visible == GLUT_VISIBLE) {
+ if (redrawContinuously)
+ glutIdleFunc(animate);
+ } else {
+ if (redrawContinuously)
+ glutIdleFunc(NULL);
+ }
+}
+
+static void
+stopMotion(int but, int time)
+{
+ if ((but == GLUT_LEFT_BUTTON && mode == MoveView) ||
+ (but == GLUT_MIDDLE_BUTTON && mode == MoveTexture)) {
+ } else {
+ return;
+ }
+
+ if (time == lastTime) {
+ /* redrawContinuously = GL_TRUE;*/
+ glutIdleFunc(animate);
+ } else {
+ angle = 0.0;
+ redrawContinuously = GL_FALSE;
+ glutIdleFunc(0);
+ }
+ if (!redrawContinuously) {
+ mode = MoveNone;
+ }
+}
+
+static void
+trackMotion(int x, int y)
+{
+ float curPos[3], dx, dy, dz;
+
+ ptov(x, y, winWidth, winHeight, curPos);
+
+ dx = curPos[0] - lastPos[0];
+ dy = curPos[1] - lastPos[1];
+ dz = curPos[2] - lastPos[2];
+ angle = 90.0 * sqrt(dx * dx + dy * dy + dz * dz);
+
+ axis[0] = lastPos[1] * curPos[2] - lastPos[2] * curPos[1];
+ axis[1] = lastPos[2] * curPos[0] - lastPos[0] * curPos[2];
+ axis[2] = lastPos[0] * curPos[1] - lastPos[1] * curPos[0];
+
+ lastTime = glutGet(GLUT_ELAPSED_TIME);
+ lastPos[0] = curPos[0];
+ lastPos[1] = curPos[1];
+ lastPos[2] = curPos[2];
+ glutPostRedisplay();
+}
+
+/*****************************************************************/
+
+static void
+object(void)
+{
+ static int object;
+
+ object++;
+ object %= 3;
+ switch (object) {
+ case 0:
+ drawObject = drawCube;
+ break;
+ case 1:
+ drawObject = drawDodecahedron;
+ break;
+ case 2:
+ drawObject = drawSphere;
+ break;
+ default:
+ break;
+ }
+}
+
+static void
+nop(void)
+{
+}
+
+static void
+texture(void)
+{
+ static int texture = 0;
+
+ texture++;
+ texture %= 3;
+ if (texture == 1 && texFilename == NULL) {
+ /* Skip file texture if not loaded. */
+ texture++;
+ }
+ switch (texture) {
+ case 0:
+ loadTexture = nop;
+ textureEnabled = GL_FALSE;
+ break;
+ case 1:
+ loadTexture = loadImageTextures;
+ (*loadTexture) ();
+ textureEnabled = GL_TRUE;
+ break;
+ case 2:
+ loadTexture = loadSpotlightTexture;
+ (*loadTexture) ();
+ textureEnabled = GL_TRUE;
+ break;
+ default:
+ break;
+ }
+}
+
+static void
+help(void)
+{
+ printf("'h' - help\n");
+ printf("'l' - toggle linear/nearest filter\n");
+ printf("'s' - toggle projection frustum\n");
+ printf("'t' - toggle projected texture\n");
+ printf("'o' - toggle object\n");
+ printf("'z' - increase zoom factor\n");
+ printf("'Z' - decrease zoom factor\n");
+ printf("left mouse - move view\n");
+ printf("middle mouse - move projection\n");
+}
+
+/* ARGSUSED1 */
+static void
+key(unsigned char key, int x, int y)
+{
+ switch (key) {
+ case '\033':
+ exit(0);
+ break;
+ case 'l':
+ linearFilter = !linearFilter;
+ (*loadTexture) ();
+ break;
+ case 's':
+ showProjection = !showProjection;
+ break;
+ case 't':
+ texture();
+ break;
+ case 'o':
+ object();
+ break;
+ case 'z':
+ zoomFactor += 1.0;
+ glPixelZoom(zoomFactor, zoomFactor);
+ glViewport(0, 0, winWidth / zoomFactor, winHeight / zoomFactor);
+ break;
+ case 'Z':
+ zoomFactor -= 1.0;
+ if (zoomFactor < 1.0)
+ zoomFactor = 1.0;
+ glPixelZoom(zoomFactor, zoomFactor);
+ glViewport(0, 0, winWidth / zoomFactor, winHeight / zoomFactor);
+ break;
+ case 'h':
+ help();
+ break;
+ }
+ glutPostRedisplay();
+}
+
+static void
+mouse(int button, int state, int x, int y)
+{
+ if (state == GLUT_DOWN)
+ startMotion(x, y, button, glutGet(GLUT_ELAPSED_TIME));
+ else if (state == GLUT_UP)
+ stopMotion(button, glutGet(GLUT_ELAPSED_TIME));
+ glutPostRedisplay();
+}
+
+static void
+reshape(int w, int h)
+{
+ winWidth = w;
+ winHeight = h;
+ glViewport(0, 0, w / zoomFactor, h / zoomFactor);
+}
+
+
+static void
+menu(int selection)
+{
+ if (selection == 666) {
+ exit(0);
+ }
+ key((unsigned char) selection, 0, 0);
+}
+
+int
+main(int argc, char **argv)
+{
+ glutInit(&argc, argv);
+
+ if (argc > 1) {
+ NumTextures = atoi(argv[1]);
+ }
+ assert(NumTextures <= MAX_TEX);
+
+ glutInitDisplayMode(GLUT_RGBA | GLUT_DEPTH | GLUT_DOUBLE);
+ glutInitWindowSize(500,500);
+ (void) glutCreateWindow("projtex");
+ glewInit();
+
+ loadTexture = loadImageTextures;
+ drawObject = drawCube;
+ initialize();
+ glutDisplayFunc(display);
+ glutKeyboardFunc(key);
+ glutReshapeFunc(reshape);
+ glutMouseFunc(mouse);
+ glutMotionFunc(trackMotion);
+ glutVisibilityFunc(vis);
+ glutCreateMenu(menu);
+ glutAddMenuEntry("Toggle showing projection", 's');
+ glutAddMenuEntry("Switch texture", 't');
+ glutAddMenuEntry("Switch object", 'o');
+ glutAddMenuEntry("Toggle filtering", 'l');
+ glutAddMenuEntry("Quit", 666);
+ glutAttachMenu(GLUT_RIGHT_BUTTON);
+ texture();
+ glutMainLoop();
+ return 0; /* ANSI C requires main to return int. */
+}
+++ /dev/null
-
-/* projtex.c - by David Yu and David Blythe, SGI */
-
-/**
- ** Demonstrates simple projective texture mapping.
- **
- ** Button1 changes view, Button2 moves texture.
- **
- ** (See: Segal, Korobkin, van Widenfelt, Foran, and Haeberli
- ** "Fast Shadows and Lighting Effects Using Texture Mapping", SIGGRAPH '92)
- **
- ** 1994,1995 -- David G Yu
- **
- ** cc -o projtex projtex.c texture.c -lglut -lGLU -lGL -lX11 -lm
- **/
-
-#include <assert.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
-#include <GL/glew.h>
-#include <GL/glut.h>
-#if 0
-#include "texture.h"
-#else
-#include "../util/readtex.c"
-#endif
-
-
-/* Some <math.h> files do not define M_PI... */
-#ifndef M_PI
-#define M_PI 3.14159265358979323846
-#endif
-
-#define MAX_TEX 4
-int NumTextures = 1;
-
-int winWidth, winHeight;
-
-GLboolean redrawContinuously = GL_FALSE;
-
-float angle, axis[3];
-enum MoveModes {
- MoveNone, MoveView, MoveObject, MoveTexture
-};
-enum MoveModes mode = MoveNone;
-
-GLfloat objectXform[4][4];
-GLfloat textureXform[MAX_TEX][4][4];
-
-void (*drawObject) (void);
-void (*loadTexture) (void);
-GLboolean textureEnabled = GL_TRUE;
-GLboolean showProjection = GL_TRUE;
-GLboolean linearFilter = GL_TRUE;
-
-char *texFilename[MAX_TEX] = {
- "../images/girl.rgb",
- "../images/tile.rgb",
- "../images/bw.rgb",
- "../images/reflect.rgb"
-};
-
-
-GLfloat zoomFactor = 1.0;
-
-/*****************************************************************/
-
-
-void ActiveTexture(int i)
-{
- glActiveTextureARB(i);
-}
-
-
-/* matrix = identity */
-void
-matrixIdentity(GLfloat matrix[16])
-{
- matrix[0] = 1.0;
- matrix[1] = 0.0;
- matrix[2] = 0.0;
- matrix[3] = 0.0;
- matrix[4] = 0.0;
- matrix[5] = 1.0;
- matrix[6] = 0.0;
- matrix[7] = 0.0;
- matrix[8] = 0.0;
- matrix[9] = 0.0;
- matrix[10] = 1.0;
- matrix[11] = 0.0;
- matrix[12] = 0.0;
- matrix[13] = 0.0;
- matrix[14] = 0.0;
- matrix[15] = 1.0;
-}
-
-/* matrix2 = transpose(matrix1) */
-void
-matrixTranspose(GLfloat matrix2[16], GLfloat matrix1[16])
-{
- matrix2[0] = matrix1[0];
- matrix2[1] = matrix1[4];
- matrix2[2] = matrix1[8];
- matrix2[3] = matrix1[12];
-
- matrix2[4] = matrix1[1];
- matrix2[5] = matrix1[5];
- matrix2[6] = matrix1[9];
- matrix2[7] = matrix1[13];
-
- matrix2[8] = matrix1[2];
- matrix2[9] = matrix1[6];
- matrix2[10] = matrix1[10];
- matrix2[11] = matrix1[14];
-
- matrix2[12] = matrix1[3];
- matrix2[13] = matrix1[7];
- matrix2[14] = matrix1[14];
- matrix2[15] = matrix1[15];
-}
-
-/*****************************************************************/
-
-/* load SGI .rgb image (pad with a border of the specified width and color) */
-#if 0
-static void
-imgLoad(char *filenameIn, int borderIn, GLfloat borderColorIn[4],
- int *wOut, int *hOut, GLubyte ** imgOut)
-{
- int border = borderIn;
- int width, height;
- int w, h;
- GLubyte *image, *img, *p;
- int i, j, components;
-
- image = (GLubyte *) read_texture(filenameIn, &width, &height, &components);
- w = width + 2 * border;
- h = height + 2 * border;
- img = (GLubyte *) calloc(w * h, 4 * sizeof(unsigned char));
-
- p = img;
- for (j = -border; j < height + border; ++j) {
- for (i = -border; i < width + border; ++i) {
- if (0 <= j && j <= height - 1 && 0 <= i && i <= width - 1) {
- p[0] = image[4 * (j * width + i) + 0];
- p[1] = image[4 * (j * width + i) + 1];
- p[2] = image[4 * (j * width + i) + 2];
- p[3] = 0xff;
- } else {
- p[0] = borderColorIn[0] * 0xff;
- p[1] = borderColorIn[1] * 0xff;
- p[2] = borderColorIn[2] * 0xff;
- p[3] = borderColorIn[3] * 0xff;
- }
- p += 4;
- }
- }
- free(image);
- *wOut = w;
- *hOut = h;
- *imgOut = img;
-}
-#endif
-
-
-/*****************************************************************/
-
-/* Load the image file specified on the command line as the current texture */
-void
-loadImageTextures(void)
-{
- GLfloat borderColor[4] =
- {1.0, 1.0, 1.0, 1.0};
- int tex;
-
- for (tex = 0; tex < NumTextures; tex++) {
- GLubyte *image, *texData3, *texData4;
- GLint imgWidth, imgHeight;
- GLenum imgFormat;
- int i, j;
-
- printf("loading %s\n", texFilename[tex]);
- image = LoadRGBImage(texFilename[tex], &imgWidth, &imgHeight, &imgFormat);
- if (!image) {
- printf("can't find %s\n", texFilename[tex]);
- exit(1);
- }
- assert(imgFormat == GL_RGB);
-
- /* scale to 256x256 */
- texData3 = malloc(256 * 256 * 4);
- texData4 = malloc(256 * 256 * 4);
- assert(texData3);
- assert(texData4);
- gluScaleImage(imgFormat, imgWidth, imgHeight, GL_UNSIGNED_BYTE, image,
- 256, 256, GL_UNSIGNED_BYTE, texData3);
-
- /* convert to rgba */
- for (i = 0; i < 256 * 256; i++) {
- texData4[i*4+0] = texData3[i*3+0];
- texData4[i*4+1] = texData3[i*3+1];
- texData4[i*4+2] = texData3[i*3+2];
- texData4[i*4+3] = 128;
- }
-
- /* put transparent border around image */
- for (i = 0; i < 256; i++) {
- texData4[i*4+0] = 255;
- texData4[i*4+1] = 255;
- texData4[i*4+2] = 255;
- texData4[i*4+3] = 0;
- }
- j = 256 * 255 * 4;
- for (i = 0; i < 256; i++) {
- texData4[j + i*4+0] = 255;
- texData4[j + i*4+1] = 255;
- texData4[j + i*4+2] = 255;
- texData4[j + i*4+3] = 0;
- }
- for (i = 0; i < 256; i++) {
- j = i * 256 * 4;
- texData4[j+0] = 255;
- texData4[j+1] = 255;
- texData4[j+2] = 255;
- texData4[j+3] = 0;
- }
- for (i = 0; i < 256; i++) {
- j = i * 256 * 4 + 255 * 4;
- texData4[j+0] = 255;
- texData4[j+1] = 255;
- texData4[j+2] = 255;
- texData4[j+3] = 0;
- }
-
- ActiveTexture(GL_TEXTURE0_ARB + tex);
- glBindTexture(GL_TEXTURE_2D, tex + 1);
-
- glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
- glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0,
- GL_RGBA, GL_UNSIGNED_BYTE, texData4);
-
- 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);
- }
- glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
- }
-}
-
-/* Create a simple spotlight pattern and make it the current texture */
-void
-loadSpotlightTexture(void)
-{
- static int texWidth = 64, texHeight = 64;
- static GLubyte *texData;
- GLfloat borderColor[4] =
- {0.1, 0.1, 0.1, 1.0};
-
- if (!texData) {
- GLubyte *p;
- int i, j;
-
- texData = (GLubyte *) malloc(texWidth * texHeight * 4 * sizeof(GLubyte));
-
- p = texData;
- for (j = 0; j < texHeight; ++j) {
- float dy = (texHeight * 0.5 - j + 0.5) / (texHeight * 0.5);
-
- for (i = 0; i < texWidth; ++i) {
- float dx = (texWidth * 0.5 - i + 0.5) / (texWidth * 0.5);
- float r = cos(M_PI / 2.0 * sqrt(dx * dx + dy * dy));
- float c;
-
- r = (r < 0) ? 0 : r * r;
- c = 0xff * (r + borderColor[0]);
- p[0] = (c <= 0xff) ? c : 0xff;
- c = 0xff * (r + borderColor[1]);
- p[1] = (c <= 0xff) ? c : 0xff;
- c = 0xff * (r + borderColor[2]);
- p[2] = (c <= 0xff) ? c : 0xff;
- c = 0xff * (r + borderColor[3]);
- p[3] = (c <= 0xff) ? c : 0xff;
- p += 4;
- }
- }
- }
- 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);
- }
- glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, borderColor);
- gluBuild2DMipmaps(GL_TEXTURE_2D, 4, texWidth, texHeight,
- GL_RGBA, GL_UNSIGNED_BYTE, texData);
-}
-
-/*****************************************************************/
-
-void
-checkErrors(void)
-{
- GLenum error;
- while ((error = glGetError()) != GL_NO_ERROR) {
- fprintf(stderr, "Error: %s\n", (char *) gluErrorString(error));
- }
-}
-
-void
-drawCube(void)
-{
- glBegin(GL_QUADS);
-
- glNormal3f(-1.0, 0.0, 0.0);
- glColor3f(0.80, 0.50, 0.50);
- glVertex3f(-0.5, -0.5, -0.5);
- glVertex3f(-0.5, -0.5, 0.5);
- glVertex3f(-0.5, 0.5, 0.5);
- glVertex3f(-0.5, 0.5, -0.5);
-
- glNormal3f(1.0, 0.0, 0.0);
- glColor3f(0.50, 0.80, 0.50);
- glVertex3f(0.5, 0.5, 0.5);
- glVertex3f(0.5, -0.5, 0.5);
- glVertex3f(0.5, -0.5, -0.5);
- glVertex3f(0.5, 0.5, -0.5);
-
- glNormal3f(0.0, -1.0, 0.0);
- glColor3f(0.50, 0.50, 0.80);
- glVertex3f(-0.5, -0.5, -0.5);
- glVertex3f(0.5, -0.5, -0.5);
- glVertex3f(0.5, -0.5, 0.5);
- glVertex3f(-0.5, -0.5, 0.5);
-
- glNormal3f(0.0, 1.0, 0.0);
- glColor3f(0.50, 0.80, 0.80);
- glVertex3f(0.5, 0.5, 0.5);
- glVertex3f(0.5, 0.5, -0.5);
- glVertex3f(-0.5, 0.5, -0.5);
- glVertex3f(-0.5, 0.5, 0.5);
-
- glNormal3f(0.0, 0.0, -1.0);
- glColor3f(0.80, 0.50, 0.80);
- glVertex3f(-0.5, -0.5, -0.5);
- glVertex3f(-0.5, 0.5, -0.5);
- glVertex3f(0.5, 0.5, -0.5);
- glVertex3f(0.5, -0.5, -0.5);
-
- glNormal3f(0.0, 0.0, 1.0);
- glColor3f(1.00, 0.80, 0.50);
- glVertex3f(0.5, 0.5, 0.5);
- glVertex3f(-0.5, 0.5, 0.5);
- glVertex3f(-0.5, -0.5, 0.5);
- glVertex3f(0.5, -0.5, 0.5);
- glEnd();
-}
-
-void
-drawDodecahedron(void)
-{
-#define A (0.5 * 1.61803) /* (sqrt(5) + 1) / 2 */
-#define B (0.5 * 0.61803) /* (sqrt(5) - 1) / 2 */
-#define C (0.5 * 1.0)
- GLfloat vertexes[20][3] =
- {
- {-A, 0.0, B},
- {-A, 0.0, -B},
- {A, 0.0, -B},
- {A, 0.0, B},
- {B, -A, 0.0},
- {-B, -A, 0.0},
- {-B, A, 0.0},
- {B, A, 0.0},
- {0.0, B, -A},
- {0.0, -B, -A},
- {0.0, -B, A},
- {0.0, B, A},
- {-C, -C, C},
- {-C, -C, -C},
- {C, -C, -C},
- {C, -C, C},
- {-C, C, C},
- {-C, C, -C},
- {C, C, -C},
- {C, C, C},
- };
-#undef A
-#undef B
-#undef C
- GLint polygons[12][5] =
- {
- {0, 12, 10, 11, 16},
- {1, 17, 8, 9, 13},
- {2, 14, 9, 8, 18},
- {3, 19, 11, 10, 15},
- {4, 14, 2, 3, 15},
- {5, 12, 0, 1, 13},
- {6, 17, 1, 0, 16},
- {7, 19, 3, 2, 18},
- {8, 17, 6, 7, 18},
- {9, 14, 4, 5, 13},
- {10, 12, 5, 4, 15},
- {11, 19, 7, 6, 16},
- };
- int i;
-
- glColor3f(0.75, 0.75, 0.75);
- for (i = 0; i < 12; ++i) {
- GLfloat *p0, *p1, *p2, d;
- GLfloat u[3], v[3], n[3];
-
- p0 = &vertexes[polygons[i][0]][0];
- p1 = &vertexes[polygons[i][1]][0];
- p2 = &vertexes[polygons[i][2]][0];
-
- u[0] = p2[0] - p1[0];
- u[1] = p2[1] - p1[1];
- u[2] = p2[2] - p1[2];
-
- v[0] = p0[0] - p1[0];
- v[1] = p0[1] - p1[1];
- v[2] = p0[2] - p1[2];
-
- n[0] = u[1] * v[2] - u[2] * v[1];
- n[1] = u[2] * v[0] - u[0] * v[2];
- n[2] = u[0] * v[1] - u[1] * v[0];
-
- d = 1.0 / sqrt(n[0] * n[0] + n[1] * n[1] + n[2] * n[2]);
- n[0] *= d;
- n[1] *= d;
- n[2] *= d;
-
- glBegin(GL_POLYGON);
- glNormal3fv(n);
- glVertex3fv(p0);
- glVertex3fv(p1);
- glVertex3fv(p2);
- glVertex3fv(vertexes[polygons[i][3]]);
- glVertex3fv(vertexes[polygons[i][4]]);
- glEnd();
- }
-}
-
-void
-drawSphere(void)
-{
- int numMajor = 24;
- int numMinor = 32;
- float radius = 0.8;
- double majorStep = (M_PI / numMajor);
- double minorStep = (2.0 * M_PI / numMinor);
- int i, j;
-
- glColor3f(0.50, 0.50, 0.50);
- for (i = 0; i < numMajor; ++i) {
- double a = i * majorStep;
- double b = a + majorStep;
- double r0 = radius * sin(a);
- double r1 = radius * sin(b);
- GLfloat z0 = radius * cos(a);
- GLfloat z1 = radius * cos(b);
-
- glBegin(GL_TRIANGLE_STRIP);
- for (j = 0; j <= numMinor; ++j) {
- double c = j * minorStep;
- GLfloat x = cos(c);
- GLfloat y = sin(c);
-
- glNormal3f((x * r0) / radius, (y * r0) / radius, z0 / radius);
- glTexCoord2f(j / (GLfloat) numMinor, i / (GLfloat) numMajor);
- glVertex3f(x * r0, y * r0, z0);
-
- glNormal3f((x * r1) / radius, (y * r1) / radius, z1 / radius);
- glTexCoord2f(j / (GLfloat) numMinor, (i + 1) / (GLfloat) numMajor);
- glVertex3f(x * r1, y * r1, z1);
- }
- glEnd();
- }
-}
-
-/*****************************************************************/
-
-float xmin = -0.035, xmax = 0.035;
-float ymin = -0.035, ymax = 0.035;
-float nnear = 0.1;
-float ffar = 1.9;
-float distance = -1.0;
-
-static void
-loadTextureProjection(int texUnit, GLfloat m[16])
-{
- GLfloat mInverse[4][4];
-
- /* Should use true inverse, but since m consists only of rotations, we can
- just use the transpose. */
- matrixTranspose((GLfloat *) mInverse, m);
-
- ActiveTexture(GL_TEXTURE0_ARB + texUnit);
- glMatrixMode(GL_TEXTURE);
- glLoadIdentity();
- glTranslatef(0.5, 0.5, 0.0);
- glScalef(0.5, 0.5, 1.0);
- glFrustum(xmin, xmax, ymin, ymax, nnear, ffar);
- glTranslatef(0.0, 0.0, distance);
- glMultMatrixf((GLfloat *) mInverse);
- glMatrixMode(GL_MODELVIEW);
-}
-
-static void
-drawTextureProjection(void)
-{
- float t = ffar / nnear;
- GLfloat n[4][3];
- GLfloat f[4][3];
-
- n[0][0] = xmin;
- n[0][1] = ymin;
- n[0][2] = -(nnear + distance);
-
- n[1][0] = xmax;
- n[1][1] = ymin;
- n[1][2] = -(nnear + distance);
-
- n[2][0] = xmax;
- n[2][1] = ymax;
- n[2][2] = -(nnear + distance);
-
- n[3][0] = xmin;
- n[3][1] = ymax;
- n[3][2] = -(nnear + distance);
-
- f[0][0] = xmin * t;
- f[0][1] = ymin * t;
- f[0][2] = -(ffar + distance);
-
- f[1][0] = xmax * t;
- f[1][1] = ymin * t;
- f[1][2] = -(ffar + distance);
-
- f[2][0] = xmax * t;
- f[2][1] = ymax * t;
- f[2][2] = -(ffar + distance);
-
- f[3][0] = xmin * t;
- f[3][1] = ymax * t;
- f[3][2] = -(ffar + distance);
-
- glColor3f(1.0, 1.0, 0.0);
- glBegin(GL_LINE_LOOP);
- glVertex3fv(n[0]);
- glVertex3fv(n[1]);
- glVertex3fv(n[2]);
- glVertex3fv(n[3]);
- glVertex3fv(f[3]);
- glVertex3fv(f[2]);
- glVertex3fv(f[1]);
- glVertex3fv(f[0]);
- glVertex3fv(n[0]);
- glVertex3fv(n[1]);
- glVertex3fv(f[1]);
- glVertex3fv(f[0]);
- glVertex3fv(f[3]);
- glVertex3fv(f[2]);
- glVertex3fv(n[2]);
- glVertex3fv(n[3]);
- glEnd();
-}
-
-/*****************************************************************/
-
-void
-initialize(void)
-{
- GLfloat light0Pos[4] =
- {0.3, 0.3, 0.0, 1.0};
- GLfloat matAmb[4] =
- {0.01, 0.01, 0.01, 1.00};
- GLfloat matDiff[4] =
- {0.65, 0.65, 0.65, 1.00};
- GLfloat matSpec[4] =
- {0.30, 0.30, 0.30, 1.00};
- GLfloat matShine = 10.0;
- GLfloat eyePlaneS[] =
- {1.0, 0.0, 0.0, 0.0};
- GLfloat eyePlaneT[] =
- {0.0, 1.0, 0.0, 0.0};
- GLfloat eyePlaneR[] =
- {0.0, 0.0, 1.0, 0.0};
- GLfloat eyePlaneQ[] =
- {0.0, 0.0, 0.0, 1.0};
- int i;
-
- /* Setup Misc. */
- glClearColor(0.41, 0.41, 0.31, 0.0);
-
- glEnable(GL_DEPTH_TEST);
-
- /* glLineWidth(2.0);*/
-
- glCullFace(GL_FRONT);
- glEnable(GL_CULL_FACE);
-
- glMatrixMode(GL_PROJECTION);
- glFrustum(-0.5, 0.5, -0.5, 0.5, 1, 3);
- glMatrixMode(GL_MODELVIEW);
- glTranslatef(0, 0, -2);
-
- matrixIdentity((GLfloat *) objectXform);
- for (i = 0; i < NumTextures; i++) {
- matrixIdentity((GLfloat *) textureXform[i]);
- }
-
- glMatrixMode(GL_PROJECTION);
- glPushMatrix();
- glLoadIdentity();
- glOrtho(0, 1, 0, 1, -1, 1);
- glMatrixMode(GL_MODELVIEW);
- glPushMatrix();
- glLoadIdentity();
-
- glRasterPos2i(0, 0);
-
- glPopMatrix();
- glMatrixMode(GL_PROJECTION);
- glPopMatrix();
- glMatrixMode(GL_MODELVIEW);
-
- /* Setup Lighting */
- glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, matAmb);
- glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, matDiff);
- glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, matSpec);
- glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, matShine);
-
- glEnable(GL_COLOR_MATERIAL);
-
- glLightfv(GL_LIGHT0, GL_POSITION, light0Pos);
- glEnable(GL_LIGHT0);
-
- glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
- glEnable(GL_LIGHTING);
-
- /* Setup Texture */
-
- (*loadTexture) ();
-
-
- for (i = 0; i < NumTextures; i++) {
- ActiveTexture(GL_TEXTURE0_ARB + i);
-
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
- glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
- glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
-
- glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
- glTexGenfv(GL_S, GL_EYE_PLANE, eyePlaneS);
-
- glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
- glTexGenfv(GL_T, GL_EYE_PLANE, eyePlaneT);
-
- glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
- glTexGenfv(GL_R, GL_EYE_PLANE, eyePlaneR);
-
- glTexGeni(GL_Q, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
- glTexGenfv(GL_Q, GL_EYE_PLANE, eyePlaneQ);
- }
-}
-
-void
-display(void)
-{
- int i;
-
- glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
- if (textureEnabled) {
- if (mode == MoveTexture || mode == MoveView) {
- /* Have OpenGL compute the new transformation (simple but slow). */
- for (i = 0; i < NumTextures; i++) {
- glPushMatrix();
- glLoadIdentity();
-#if 0
- if (i & 1)
- glRotatef(angle, axis[0], axis[1], axis[2]);
- else
-#endif
- glRotatef(angle*(i+1), axis[0], axis[1], axis[2]);
-
- glMultMatrixf((GLfloat *) textureXform[i]);
- glGetFloatv(GL_MODELVIEW_MATRIX, (GLfloat *) textureXform[i]);
- glPopMatrix();
- }
- }
- for (i = 0; i < NumTextures; i++) {
- loadTextureProjection(i, (GLfloat *) textureXform[i]);
- }
-
- if (showProjection) {
- for (i = 0; i < NumTextures; i++) {
- ActiveTexture(GL_TEXTURE0_ARB + i);
- glPushMatrix();
- glMultMatrixf((GLfloat *) textureXform[i]);
- glDisable(GL_LIGHTING);
- drawTextureProjection();
- glEnable(GL_LIGHTING);
- glPopMatrix();
- }
- }
- for (i = 0; i < NumTextures; i++) {
- ActiveTexture(GL_TEXTURE0_ARB + i);
- glEnable(GL_TEXTURE_2D);
- glEnable(GL_TEXTURE_GEN_S);
- glEnable(GL_TEXTURE_GEN_T);
- glEnable(GL_TEXTURE_GEN_R);
- glEnable(GL_TEXTURE_GEN_Q);
- }
- }
- if (mode == MoveObject || mode == MoveView) {
- /* Have OpenGL compute the new transformation (simple but slow). */
- glPushMatrix();
- glLoadIdentity();
- glRotatef(angle, axis[0], axis[1], axis[2]);
- glMultMatrixf((GLfloat *) objectXform);
- glGetFloatv(GL_MODELVIEW_MATRIX, (GLfloat *) objectXform);
- glPopMatrix();
- }
- glPushMatrix();
- glMultMatrixf((GLfloat *) objectXform);
- (*drawObject) ();
- glPopMatrix();
-
- for (i = 0; i < NumTextures; i++) {
- ActiveTexture(GL_TEXTURE0_ARB + i);
- glDisable(GL_TEXTURE_2D);
- glDisable(GL_TEXTURE_GEN_S);
- glDisable(GL_TEXTURE_GEN_T);
- glDisable(GL_TEXTURE_GEN_R);
- glDisable(GL_TEXTURE_GEN_Q);
- }
-
- if (zoomFactor > 1.0) {
- glDisable(GL_DEPTH_TEST);
- glCopyPixels(0, 0, winWidth / zoomFactor, winHeight / zoomFactor, GL_COLOR);
- glEnable(GL_DEPTH_TEST);
- }
- glFlush();
- glutSwapBuffers();
- checkErrors();
-}
-
-/*****************************************************************/
-
-/* simple trackball-like motion control */
-float lastPos[3];
-int lastTime;
-
-void
-ptov(int x, int y, int width, int height, float v[3])
-{
- float d, a;
-
- /* project x,y onto a hemi-sphere centered within width, height */
- v[0] = (2.0 * x - width) / width;
- v[1] = (height - 2.0 * y) / height;
- d = sqrt(v[0] * v[0] + v[1] * v[1]);
- v[2] = cos((M_PI / 2.0) * ((d < 1.0) ? d : 1.0));
- a = 1.0 / sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
- v[0] *= a;
- v[1] *= a;
- v[2] *= a;
-}
-
-void
-startMotion(int x, int y, int but, int time)
-{
- if (but == GLUT_LEFT_BUTTON) {
- mode = MoveView;
- } else if (but == GLUT_MIDDLE_BUTTON) {
- mode = MoveTexture;
- } else {
- return;
- }
-
- lastTime = time;
- ptov(x, y, winWidth, winHeight, lastPos);
-}
-
-void
-animate(void)
-{
- glutPostRedisplay();
-}
-
-void
-vis(int visible)
-{
- if (visible == GLUT_VISIBLE) {
- if (redrawContinuously)
- glutIdleFunc(animate);
- } else {
- if (redrawContinuously)
- glutIdleFunc(NULL);
- }
-}
-
-void
-stopMotion(int but, int time)
-{
- if ((but == GLUT_LEFT_BUTTON && mode == MoveView) ||
- (but == GLUT_MIDDLE_BUTTON && mode == MoveTexture)) {
- } else {
- return;
- }
-
- if (time == lastTime) {
- /* redrawContinuously = GL_TRUE;*/
- glutIdleFunc(animate);
- } else {
- angle = 0.0;
- redrawContinuously = GL_FALSE;
- glutIdleFunc(0);
- }
- if (!redrawContinuously) {
- mode = MoveNone;
- }
-}
-
-void
-trackMotion(int x, int y)
-{
- float curPos[3], dx, dy, dz;
-
- ptov(x, y, winWidth, winHeight, curPos);
-
- dx = curPos[0] - lastPos[0];
- dy = curPos[1] - lastPos[1];
- dz = curPos[2] - lastPos[2];
- angle = 90.0 * sqrt(dx * dx + dy * dy + dz * dz);
-
- axis[0] = lastPos[1] * curPos[2] - lastPos[2] * curPos[1];
- axis[1] = lastPos[2] * curPos[0] - lastPos[0] * curPos[2];
- axis[2] = lastPos[0] * curPos[1] - lastPos[1] * curPos[0];
-
- lastTime = glutGet(GLUT_ELAPSED_TIME);
- lastPos[0] = curPos[0];
- lastPos[1] = curPos[1];
- lastPos[2] = curPos[2];
- glutPostRedisplay();
-}
-
-/*****************************************************************/
-
-void
-object(void)
-{
- static int object;
-
- object++;
- object %= 3;
- switch (object) {
- case 0:
- drawObject = drawCube;
- break;
- case 1:
- drawObject = drawDodecahedron;
- break;
- case 2:
- drawObject = drawSphere;
- break;
- default:
- break;
- }
-}
-
-static void
-nop(void)
-{
-}
-
-void
-texture(void)
-{
- static int texture = 0;
-
- texture++;
- texture %= 3;
- if (texture == 1 && texFilename == NULL) {
- /* Skip file texture if not loaded. */
- texture++;
- }
- switch (texture) {
- case 0:
- loadTexture = nop;
- textureEnabled = GL_FALSE;
- break;
- case 1:
- loadTexture = loadImageTextures;
- (*loadTexture) ();
- textureEnabled = GL_TRUE;
- break;
- case 2:
- loadTexture = loadSpotlightTexture;
- (*loadTexture) ();
- textureEnabled = GL_TRUE;
- break;
- default:
- break;
- }
-}
-
-void
-help(void)
-{
- printf("'h' - help\n");
- printf("'l' - toggle linear/nearest filter\n");
- printf("'s' - toggle projection frustum\n");
- printf("'t' - toggle projected texture\n");
- printf("'o' - toggle object\n");
- printf("'z' - increase zoom factor\n");
- printf("'Z' - decrease zoom factor\n");
- printf("left mouse - move view\n");
- printf("middle mouse - move projection\n");
-}
-
-/* ARGSUSED1 */
-void
-key(unsigned char key, int x, int y)
-{
- switch (key) {
- case '\033':
- exit(0);
- break;
- case 'l':
- linearFilter = !linearFilter;
- (*loadTexture) ();
- break;
- case 's':
- showProjection = !showProjection;
- break;
- case 't':
- texture();
- break;
- case 'o':
- object();
- break;
- case 'z':
- zoomFactor += 1.0;
- glPixelZoom(zoomFactor, zoomFactor);
- glViewport(0, 0, winWidth / zoomFactor, winHeight / zoomFactor);
- break;
- case 'Z':
- zoomFactor -= 1.0;
- if (zoomFactor < 1.0)
- zoomFactor = 1.0;
- glPixelZoom(zoomFactor, zoomFactor);
- glViewport(0, 0, winWidth / zoomFactor, winHeight / zoomFactor);
- break;
- case 'h':
- help();
- break;
- }
- glutPostRedisplay();
-}
-
-void
-mouse(int button, int state, int x, int y)
-{
- if (state == GLUT_DOWN)
- startMotion(x, y, button, glutGet(GLUT_ELAPSED_TIME));
- else if (state == GLUT_UP)
- stopMotion(button, glutGet(GLUT_ELAPSED_TIME));
- glutPostRedisplay();
-}
-
-void
-reshape(int w, int h)
-{
- winWidth = w;
- winHeight = h;
- glViewport(0, 0, w / zoomFactor, h / zoomFactor);
-}
-
-
-void
-menu(int selection)
-{
- if (selection == 666) {
- exit(0);
- }
- key((unsigned char) selection, 0, 0);
-}
-
-int
-main(int argc, char **argv)
-{
- glutInit(&argc, argv);
-
- if (argc > 1) {
- NumTextures = atoi(argv[1]);
- }
- assert(NumTextures <= MAX_TEX);
-
- glutInitDisplayMode(GLUT_RGBA | GLUT_DEPTH | GLUT_DOUBLE);
- (void) glutCreateWindow("projtex");
- glewInit();
-
- loadTexture = loadImageTextures;
- drawObject = drawCube;
- initialize();
- glutDisplayFunc(display);
- glutKeyboardFunc(key);
- glutReshapeFunc(reshape);
- glutMouseFunc(mouse);
- glutMotionFunc(trackMotion);
- glutVisibilityFunc(vis);
- glutCreateMenu(menu);
- glutAddMenuEntry("Toggle showing projection", 's');
- glutAddMenuEntry("Switch texture", 't');
- glutAddMenuEntry("Switch object", 'o');
- glutAddMenuEntry("Toggle filtering", 'l');
- glutAddMenuEntry("Quit", 666);
- glutAttachMenu(GLUT_RIGHT_BUTTON);
- texture();
- glutMainLoop();
- return 0; /* ANSI C requires main to return int. */
-}
projects / mesa.git / commitdiff