纹理盒子.cpp

【核心代码】

#include <gl/glut.h>
#include <stdio.h>       //标准输入/输出头文件
#include <gl/glaux.h>      //用于位图加载的库文件

#define WindowWidth 400
#define WindowHeight 400
#define WindowTitle "OpenGL纹理测试"

GLuint texture[6];  // 创建一个全局的纹理数组，用来存储将位图转换之后得到的纹理，对应于立方体的6个面
GLfloat xrot; //沿着X旋转的变量
GLfloat yrot; //沿着Y旋转的变量
GLfloat zrot; //沿着z旋转的变量


			  /*加载位图文件*/
AUX_RGBImageRec *LoadBMP(char *Filename)  //根据位图文件名加载
{
	FILE *file = NULL;    //文件指针
	if (!Filename)
	{
		return NULL;   //如果没有指定位图文件名称就返回NULL
	}

	file = fopen(Filename, "r");   //根据指定的位图文件名称，打开该位图文件
	if (file)   //如果该位图文件存在
	{
		fclose(file);  // 因为只是需要判断问题是否存在，而不需要对位图文件进行写操作，所以关闭位图文件
		return auxDIBImageLoad(Filename);    // 其实，只需要一个真正存在的位图文件的名称，实现加载位图文件，并返回一个指针
	}

	return NULL;   //位图文件加载失败就返回NULL
}


//读入纹理
bool LoadTexture()
{
	bool Status = FALSE;
	AUX_RGBImageRec *TextureImage[6];
	memset(TextureImage, 0, sizeof(void*) * 6);		//设置的只有一个纹理

	TextureImage[0] = LoadBMP("PIC/No1.bmp");		//载入图片纹理1
	TextureImage[1] = LoadBMP("PIC/No2.bmp");		//载入图片纹理2
	TextureImage[2] = LoadBMP("PIC/No3.bmp");		//载入图片纹理3
	TextureImage[3] = LoadBMP("PIC/No4.bmp");
	TextureImage[4] = LoadBMP("PIC/No5.bmp");
	TextureImage[5] = LoadBMP("PIC/No6.bmp");
	if (TextureImage[0] && TextureImage[1] && TextureImage[2] && TextureImage[3] && TextureImage[4] && TextureImage[5])
	{
		Status = true;

		for (int i = 0; i<6; i  )
		{
			glGenTextures(1, &texture[i]);		//创建纹理
												//设置纹理映射模式
			glBindTexture(GL_TEXTURE_2D, texture[i]);		//绑定纹理
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
			//具体指定二维纹理图元
			glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[i]->sizeX, TextureImage[i]->sizeY, 0,
				GL_RGB, GL_UNSIGNED_BYTE, TextureImage[i]->data);
		}

	}


	//释放后面无用的资源
	for (int i = 0; i<6; i  )
	{

		if (TextureImage)
		{
			if (TextureImage[i]->data)
			{
				free(TextureImage[i]->data);
			}//if
			free(TextureImage[i]);
		}//if

	}//for

	return Status;

}

int init()
{
	if (LoadTexture() == false)
	{
		return 0;
	}//if
	 //初始化纹理
	glEnable(GL_DEPTH_TEST);
	glEnable(GL_TEXTURE_2D);

	xrot = 0.0f;
	yrot = 0.0f;
	zrot = 0.0f;

	return TRUE;
}

void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glLoadIdentity();
	glTranslatef(0.0f, 0.0f, -5.0f);

	glRotatef(xrot, 1.0f, 0.0f, 0.0f);
	glRotatef(yrot, 0.0f, 1.0f, 0.0f);
	glRotatef(zrot, 0.0f, 0.0f, 1.0f);

	//Front Face
	glBindTexture(GL_TEXTURE_2D, texture[0]);  //   选择第一个纹理texture[0]，进行贴纹理
	glBegin(GL_QUADS);
	glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
	glTexCoord2f(1.0f, 0.0f); glVertex3f(1.0f, -1.0f, 1.0f);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(1.0f, 1.0f, 1.0f);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
	glEnd();
	//Back Face
	glBindTexture(GL_TEXTURE_2D, texture[1]);  //   选择第二个纹理，进行贴纹理
	glBegin(GL_QUADS);
	glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(1.0f, 1.0f, -1.0f);
	glTexCoord2f(0.0f, 0.0f); glVertex3f(1.0f, -1.0f, -1.0f);
	glEnd();
	//Top Face
	glBindTexture(GL_TEXTURE_2D, texture[2]);  //   选择第三个纹理，进行贴纹理
	glBegin(GL_QUADS);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
	glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
	glTexCoord2f(1.0f, 0.0f); glVertex3f(1.0f, 1.0f, 1.0f);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(1.0f, 1.0f, -1.0f);
	glEnd();
	//Bottom Face
	glBindTexture(GL_TEXTURE_2D, texture[3]);  //   选择第四个纹理，进行贴纹理
	glBegin(GL_QUADS);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(1.0f, -1.0f, -1.0f);
	glTexCoord2f(0.0f, 0.0f); glVertex3f(1.0f, -1.0f, 1.0f);
	glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
	glEnd();
	//Right Face
	glBindTexture(GL_TEXTURE_2D, texture[4]);  //   选择第五个纹理，进行贴纹理
	glBegin(GL_QUADS);
	glTexCoord2f(1.0f, 0.0f); glVertex3f(1.0f, -1.0f, -1.0f);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(1.0f, 1.0f, -1.0f);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(1.0f, 1.0f, 1.0f);
	glTexCoord2f(0.0f, 0.0f); glVertex3f(1.0f, -1.0f, 1.0f);
	glEnd();
	//Left Face
	glBindTexture(GL_TEXTURE_2D, texture[5]);  //   选择第六个纹理，进行贴纹理
	glBegin(GL_QUADS);
	glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
	glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
	glEnd();

	glFlush();
	glutSwapBuffers();   //动画实现第二步：交互双缓冲
}



void reshape(int w, int h)
{
	glViewport(0, 0, (GLsizei)WindowWidth, (GLsizei)WindowHeight);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(90.0, (GLfloat)WindowWidth / (GLfloat)WindowHeight, 1.0, 100.0);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

}

/*动画效果 */
void myIdle(void) {
	xrot  = 0.3f;
	yrot  = 0.2f;
	zrot  = 0.4f;

	glutPostRedisplay();
}

int main(int argc, char* argv[])
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);//动画实现第一步：开启双缓冲
	glutInitWindowPosition(100, 100);
	glutInitWindowSize(WindowWidth, WindowHeight);
	glutCreateWindow(WindowTitle);
	init();
	glutDisplayFunc(&display);
	glutReshapeFunc(reshape);
	glutIdleFunc(&myIdle); // 动画实现第三步：空闲时绘制
	glutMainLoop();
	return 0;
}