Question

opengl纹理映射的问题

int LoadGLTextures()
{
int Status=FALSE;
AUX_RGBImageRec *TextureImage[1];
memset(TextureImage,0,sizeof(void *)*1);
if (TextureImage[0]=LoadBMP("tex/1.bmp"))
{
Status=TRUE;
glGenTextures(1, &texture[0]); //载入纹理
glBindTexture(GL_TEXTURE_2D, texture[0]);
glTexImage2D(GL_TEXTURE_2D,0,3,TextureImage[0]->sizeX,TextureImage[0]->sizeY,0,GL_RGB,GL_UNSIGNED_BYTE,TextureImage[0]->data);
}
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); // 线形滤波
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
if (TextureImage[0]) // 纹理是否存在
{
if (TextureImage[0]->data) // 纹理图像是否存在
{
free(TextureImage[0]->data); // 释放纹理图像占用的内存
}
free(TextureImage[0]); // 释放图像结构
}
return Status;
}
void RenderScene(void)
{
static float fElect1 = 0.0f; //公转
static float fElect2 = 0.0f; //月亮转

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity(); // 重置模型视图矩阵

//设置光源的位置
GLfloat position[] = { 0.0f, 0.0f, 1.5f, 1.0f };
glLightfv (GL_LIGHT0, GL_POSITION, position);
glTranslated (0.0f, 0.0f, -200); //向Z负移200

//绘制太阳
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, texture[0]); //加载图片
GLUquadricObj *pSphere =gluNewQuadric();
gluQuadricDrawStyle(pSphere, GL_FILL);
gluQuadricNormals(pSphere, GLU_SMOOTH);
gluQuadricTexture(pSphere, TRUE);
glColor3f (1.0f, 1.0f, 1.0f);
gluSphere(pSphere,30,50,50);
//glutSolidSphere (30.0f, 50.0f, 50.0f);
glPushMatrix(); //保存坐标轴位置
图片加载不上去，这是为什么?
AUX_RGBImageRec *LoadBMP(char *Filename)
{
FILE *File=NULL;
if (!Filename) // 确保文件名已提供。
{
return NULL; // 如果没提供，返回 NULL
}
File=fopen(Filename,"r");
if (File) // 文件存在么?
{
fclose(File); // 关闭句柄
return auxDIBImageLoad(Filename); //载入位图并返回指针
}
return NULL;
}

Answer 1

这里贴的代码也看不出什么问题，检查纹理载入是不是有问题，图像是RGB还是RGBA之类的，我贴一段可执行的例子，你对比看看。。。

#include <GL/glut.h>
#include <stdlib.h>
#include <stdio.h>

/*  Create checkerboard texture */
#define checkImageWidth 64
#define checkImageHeight 64
static GLubyte checkImage[checkImageHeight][checkImageWidth][4];
static GLuint texName;

void makeCheckImages(void)
{
   int i, j, c;

   for (i = 0; i < checkImageHeight; i++) {
      for (j = 0; j < checkImageWidth; 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;
         checkImage[i][j][3] = (GLubyte) 255;

      }
   }
}

void init(void)
{
   glClearColor (0.0, 0.0, 0.0, 0.0);
   glShadeModel(GL_FLAT);
   glEnable(GL_DEPTH_TEST);

   makeCheckImages();
   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

   glGenTextures(1, &texName);
   glBindTexture(GL_TEXTURE_2D, texName);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,
                   GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
                   GL_NEAREST);
   glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, checkImageWidth,
                checkImageHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE,
                checkImage);

   glEnable(GL_TEXTURE_2D);
}

void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glBindTexture(GL_TEXTURE_2D, texName);

	GLUquadricObj *pSphere =gluNewQuadric();
	gluQuadricDrawStyle(pSphere, GL_FILL);
	gluQuadricNormals(pSphere, GLU_SMOOTH);
	gluQuadricTexture(pSphere, TRUE);
	glColor3f (1.0f, 1.0f, 1.0f);  
	glPushMatrix();
	glRotatef(30.0f,1.0f,0.0f,0.0f);
	gluSphere(pSphere,5,50,50);
	glPopMatrix();

	glFlush();
}

void reshape(int w, int h)
{
   glViewport(0, 0, (GLsizei) w, (GLsizei) h);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0, 30.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
   glTranslatef(0.0, 0.0, -20);
   
}

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
      case 27:
         exit(0);
         break;
   }
}

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
   glutInitWindowSize(250, 250);
   glutInitWindowPosition(100, 100);
   glutCreateWindow(argv[0]);
   init();
   glutReshapeFunc(reshape);
   glutDisplayFunc(display);
   glutKeyboardFunc (keyboard);
   glutMainLoop();
   return 0;
}