标签:style class blog code java http
VS2010/Windows 7/
1. 需包含头文件 stdio.h, glaux.h, glut.h。需要对应的lib,并添加包含路径
2. 窗口显示用glut库的函数
3. bmp图片从本地读取,再用它来生成纹理,首先用auxDIBImageLoad函数将图片数据读到AUX_RGBImageRec结构体当中。
然后
//生成纹理数据 glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data);
然后用线性滤波函数按自己要求缩放显示
//线性滤波 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
4. 图片旋转显示的时候用
glRotatef(-90,0.0f,0.0f,1.0f);
或
//贴图及映射(glTexCoord2f对应纹理坐标, glVertex2f对应矩形坐标,此处已做旋转处理) glTexCoord2f(0.0f, 0.0f); glVertex2f(-1.0f, 1.0f); glTexCoord2f(0.0f, 1.0f); glVertex2f( 1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex2f( 1.0f, -1.0f); glTexCoord2f(1.0f, 0.0f); glVertex2f(-1.0f, -1.0f);
前一种是旋转函数,后一种是直接在坐标映射时改坐标
附代码:
#include "stdafx.h" #include <stdio.h> #include <gl/glaux.h> #include<gl/glut.h> GLfloat xrot; GLfloat yrot; GLfloat zrot; GLuint texture[1]; //存储一个纹理 //读取bmp文件数据 AUX_RGBImageRec *LoadBMP(char * Filename) { FILE *File = NULL; if (!Filename) return NULL; File = fopen(Filename, "r"); if (File) { fclose(File); return auxDIBImageLoad(Filename); } return NULL; } //生成纹理 int LoadGLTextures() { int Status = FALSE; AUX_RGBImageRec *TextureImage[1]; memset(TextureImage, 0, sizeof(void *)*1); if (TextureImage[0] = LoadBMP("C:\\2.bmp")) { Status = TRUE; //注册纹理 glGenTextures(1, &texture[0]); //绑定纹理名称 glBindTexture(GL_TEXTURE_2D, texture[0]); //生成纹理数据 glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data); //线性滤波 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); } if (TextureImage[0]) { if (TextureImage[0]->data) { free(TextureImage[0]->data); } free(TextureImage[0]); } return Status; } //调用入口 int InitGL(GLvoid) { if (!LoadGLTextures()) { return false; } glEnable(GL_TEXTURE_2D); //glShadeModel(GL_SMOOTH); //设置背景色为黑色 glClearColor(0.0f, 0.0f, 0.0f, 0.0f); return TRUE; } //贴图绘制 void DrawGLScene(GLvoid) { //清除屏幕缓存 glClear(GL_COLOR_BUFFER_BIT); //重置当前的模型观察矩阵 glLoadIdentity(); /************************************** * 旋转函数备用 -90表示顺时针绕Z轴旋转90度 ***************************************/ //glRotatef(-90,0.0f,0.0f,1.0f); //开始绘制四边形 glBegin(GL_QUADS); //贴图及映射(glTexCoord2f对应纹理坐标, glVertex2f对应矩形坐标,此处已做旋转处理) glTexCoord2f(0.0f, 0.0f); glVertex2f(-1.0f, 1.0f); glTexCoord2f(0.0f, 1.0f); glVertex2f( 1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex2f( 1.0f, -1.0f); glTexCoord2f(1.0f, 0.0f); glVertex2f(-1.0f, -1.0f); glEnd(); glFlush(); //glutSwapBuffers(); } int main(int argc, char **argv) { //初始化glut运行 glutInit(&argc,argv); glutInitDisplayMode(GLUT_DEPTH|GLUT_SINGLE|GLUT_RGBA); glutInitWindowPosition(300,100); glutInitWindowSize(450, 600); glutCreateWindow("hello"); InitGL(); glutDisplayFunc(&DrawGLScene); glutMainLoop(); return 0; }
(完)
OPENGL 显示BMP图片+旋转,布布扣,bubuko.com
标签:style class blog code java http
原文地址:http://www.cnblogs.com/fwst/p/3784075.html