OpenGL书跟资源

OpenGL书和资源

y. As an additional reference, you might look at the chapter on texture mapping in
《Fundamentals of Three-Dimensional Computer Graphics by Alan Watt (Reading, Mass.: Addison-Wesley, 1990).》

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Textures are simply rectangular arrays of data - for example, colordata, luminance data, or color and alpha data. The individual values ina texture array are often called texels.

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Example 9-1 : A Texture-Mappedfs Checkerboard: checker.c#include <GL/gl.h>#include <GL/glu.h>#include "aux.h"#define    checkImageWidth 64#define    checkImageHeight 64GLubyte checkImage[checkImageWidth][checkImageHeight][3];void makeCheckImage(void){    int i, j, r, c;       for (i = 0; i < checkImageWidth; i++) {        for (j = 0; j < checkImageHeight; j++) {            c = ((((i&0x8)==0)^((j&0x8))==0))*255;            checkImage[i][j][0] = (GLubyte) c;            checkImage[i][j][1] = (GLubyte) c;            checkImage[i][j][2] = (GLubyte) c;        }    }}void myinit(void){    glClearColor (0.0, 0.0, 0.0, 0.0);    glEnable(GL_DEPTH_TEST);    glDepthFunc(GL_LEQUAL);    makeCheckImage();    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);    glTexImage2D(GL_TEXTURE_2D, 0, 3, checkImageWidth,         checkImageHeight, 0, GL_RGB, GL_UNSIGNED_BYTE,         &checkImage[0][0][0]);    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,        GL_NEAREST);    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,         GL_NEAREST);    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);    glEnable(GL_TEXTURE_2D);    glShadeModel(GL_FLAT);}void display(void){    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);    glBegin(GL_QUADS);    glTexCoord2f(0.0, 0.0); glVertex3f(-2.0, -1.0, 0.0);    glTexCoord2f(0.0, 1.0); glVertex3f(-2.0, 1.0, 0.0);    glTexCoord2f(1.0, 1.0); glVertex3f(0.0, 1.0, 0.0);    glTexCoord2f(1.0, 0.0); glVertex3f(0.0, -1.0, 0.0);    glTexCoord2f(0.0, 0.0); glVertex3f(1.0, -1.0, 0.0);    glTexCoord2f(0.0, 1.0); glVertex3f(1.0, 1.0, 0.0);    glTexCoord2f(1.0, 1.0); glVertex3f(2.41421, 1.0, -1.41421);    glTexCoord2f(1.0, 0.0); glVertex3f(2.41421, -1.0,-1.41421);    glEnd();    glFlush();}void myReshape(GLsizei w, GLsizei h){    glViewport(0, 0, w, h);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    gluPerspective(60.0, 1.0*(GLfloat)w/(GLfloat)h, 1.0, 30.0);    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();    glTranslatef(0.0, 0.0, -3.6);}int main(int argc, char** argv){    auxInitDisplayMode (AUX_SINGLE | AUX_RGBA | AUX_DEPTH);    auxInitPosition (0, 0, 500, 500);    auxInitWindow (argv[0]);    myinit();    auxReshapeFunc (myReshape);    auxMainLoop(display);}