金字塔图片纹理映射

#include"gltools.h"

#include"math3d.h"

static GLint iWidth, iHeight, iComponents; static GLenum eFormat;

static GLfloat xRot, yRot;

static GLfloat noLight[4] = {0.0f, 0.0f, 0.0f, 1.0f};

static GLfloat ambientLight[4] = {0.3f, 0.3f, 0.3f, 1.0f};

static GLfloat diffuseLight[4] = {0.7f, 0.7f, 0.7f, 1.0f};

static GLfloat brightLight[4] = {1.0f, 1.0f, 1.0f, 1.0f};

//光的位置在右上角

static GLfloat lightPos[] = { 5.0f, 5.0f, 5.0f, 1.0f};

void SetupRC()

{

glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

glCullFace(GL_BACK);

glFrontFace(GL_CCW);

glEnable(GL_CULL_FACE);

glEnable(GL_DEPTH_TEST);

//设置光照环境

glEnable(GL_LIGHTING);

glLightModelfv(GL_LIGHT_MODEL_AMBIENT, noLight);

glLightfv(GL_LIGHT0, GL_AMBIENT, ambientLight);

glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuseLight);

glLightfv(GL_LIGHT0, GL_SPECULAR, brightLight);

glLightfv(GL_LIGHT0, GL_POSITION, lightPos);

glEnable(GL_LIGHT0);

//开启颜色追踪

glEnable(GL_COLOR_MATERIAL);

glColorMaterial(GL_FRONT,

GL_AMBIENT_AND_DIFFUSE);

glMaterialfv(GL_FRONT, GL_SPECULAR, brightLight);

//镜面光加亮的范围设置大一点

glMateriali(GL_FRONT, GL_SHININESS, 30);

//读取图像文件

glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

void *pImage = NULL;

pImage = gltLoadTGA("..\\stone.tga",

&iWidth, &iHeight, &iComponents, &eFormat);

if (pImage)

{

//加载纹理，然后释放临时的内存

glTexImage2D(GL_TEXTURE_2D, 0, iComponents, iWidth, iHeight, 0, eFormat, GL_UNSIGNED_BYTE, pImage);

free(pImage);

pImage = NULL;

}

//设置纹理过滤

glTexParameteri(GL_TEXTURE_2D,

GL_TEXTURE_MIN_FILTER, GL_LINEAR);

glTexParameteri(GL_TEXTURE_2D,

GL_TEXTURE_MAG_FILTER, GL_LINEAR);

glTexParameteri(GL_TEXTURE_2D,

GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

glTexParameteri(GL_TEXTURE_2D,

GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

//设置纹理环境

glTexEnvi(GL_TEXTURE_ENV,

GL_TEXTURE_ENV_MODE, GL_MODULATE);

glEnable(GL_TEXTURE_2D);

}

void RenderScene()

{

glClear(GL_COLOR_BUFFER_BIT |

GL_DEPTH_BUFFER_BIT);

/*

金字塔顶点下标为0,底部坐标如下

1______2

| |

|______|

3 4

*/

//金字塔顶点数组

M3DVector3f vertices[5] = {{0.0f, 0.8f, 0.0f},

{-.50f, 0.0f, -.50f},

{.50f, 0.0f, -.50f},

{-.50f, 0.0f, .50f},

{.50f, 0.0f, .50f}};

//表面法线向量

M3DVector3f normal;

glPushMatrix();

//先往里和往下平移一点

glTranslatef(0.0f, -0.3f, -4.0f);

if (xRot > 360.5f)

{

xRot = 0.0f;

}

if (yRot > 360.5f)

{

yRot = 0.0f;

}

//进行旋转

glRotatef(xRot, 1.0f, 0.0f, 0.0f);

glRotatef(yRot, 0.0f, 1.0f, 0.0f);

xRot += 0.5f;

yRot += 0.5f;

glBegin(GL_TRIANGLES);

//底面的四方形由两个三角形组成

glColor3f(1.0f, 0.0f, 0.0f);

//注意法线和纹理都要在顶点之前设置

glNormal3f(0.0f, -1.0f, 0.0f);

glTexCoord2f(0.0f, 1.0f);

glVertex3fv(vertices[1]);

glTexCoord2f(1.0f, 1.0f);

glVertex3fv(vertices[2]);

glTexCoord2f(1.0f, 0.0f);

glVertex3fv(vertices[4]);

glTexCoord2f(1.0f, 0.0f);

glVertex3fv(vertices[4]);

glTexCoord2f(0.0f, 0.0f);

glVertex3fv(vertices[3]);

glTexCoord2f(0.0f, 1.0f);

glVertex3fv(vertices[1]);

//前面

glColor3f(0.0f, 1.0f, 0.0f);

m3dFindNormal(normal, vertices[0], vertices[3], vertices[4]);

glNormal3fv(normal);

glTexCoord2f(0.5f, 0.5f);

glVertex3fv(vertices[0]);

glTexCoord2f(0.0f, 0.0f);

glVertex3fv(vertices[3]);

glTexCoord2f(1.0f, 0.0f);

glVertex3fv(vertices[4]);

//左侧面

glColor3f(0.0f, 0.0f, 1.0f);

m3dFindNormal(normal, vertices[1], vertices[3], vertices[0]);

glNormal3fv(normal);

glTexCoord2f(0.0f, 0.0f);

glVertex3fv(vertices[1]);

glTexCoord2f(1.0f, 0.0f);

glVertex3fv(vertices[3]);

glTexCoord2f(0.5f, 0.5f);

glVertex3fv(vertices[0]);

//右侧面

glColor3f(0.0f, 1.0f, 1.0f);

m3dFindNormal(normal, vertices[0], vertices[4], vertices[2]);

glNormal3fv(normal);

glTexCoord2f(0.5f, 0.5f);

glVertex3fv(vertices[0]);

glTexCoord2f(0.0f, 0.0f);

glVertex3fv(vertices[4]);

glTexCoord2f(1.0f, 0.0f);

glVertex3fv(vertices[2]);

//后面

glColor3f(1.0f, 0.0f, 1.0f);

m3dFindNormal(normal, vertices[0], vertices[2], vertices[1]);

glNormal3fv(normal);

glTexCoord2f(0.5f, 0.5f);

glVertex3fv(vertices[0]);

glTexCoord2f(0.0f, 0.0f);

glVertex3fv(vertices[2]);

glTexCoord2f(1.0f, 0.0f);

glVertex3fv(vertices[1]);

glEnd();

glPopMatrix();

glutSwapBuffers();

}

void ChangeSize(GLsizei w, GLsizei h)

{

if (h == 0)

h = 1;

glViewport(0, 0, w, h);

float fAspect = (GLfloat)w/(GLfloat)h;

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluPerspective(35.0, fAspect, 1.0, 100.0);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity();

glutPostRedisplay();

}

void TimerFunc(int value)

{

glutPostRedisplay();

glutTimerFunc(60, TimerFunc, 1);

}

int main(int args, char *arv[])

{

glutInit(&args, arv);

glutInitDisplayMode(GL_RGB | GL_DOUBLE | GL_DEPTH);

glutInitWindowSize(800, 600);

glutCreateWindow("pyramid");

glutDisplayFunc(RenderScene);

glutReshapeFunc(ChangeSize);

SetupRC();

glutTimerFunc(50, TimerFunc, 1);

glutMainLoop();

return 0;

}