注意:需要在配置好OpenGL的编程环境中运行下列代码,环境配置文章可参考:
OpenGL在Mac项目上的配置
下面的代码,直接放置在main.cpp文件中即可:
#include "GLTools.h" #include "GLMatrixStack.h" #include "GLFrame.h" #include "GLFrustum.h" #include "GLGeometryTransform.h" #include "GLBatch.h" #include "math.h" #include <GLUT/GLUT.h> GLShaderManager shaderManager; GLMatrixStack modelViewMatrix; GLMatrixStack projectionMatrix; GLGeometryTransform transformPipeline; GLBatch tubeBatch; GLBatch innerBatch; GLFrustum viewFrustum; GLFrame viewFrame; float fZ = 100.f; float bZ = -100.f; // 窗口渲染调用 void RenderScene(void) { // 清除缓存区 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // 压栈,物体矩阵 modelViewMatrix.PushMatrix(viewFrame); // 默认红色光源着色 GLfloat vRed[] = {1.0f, 0.0f, 0.0f, 1.0f}; shaderManager.UseStockShader(GLT_SHADER_DEFAULT_LIGHT, transformPipeline.GetModelViewMatrix(), transformPipeline.GetProjectionMatrix(), vRed); tubeBatch.Draw(); // 默认灰色光源着色 GLfloat vGray[] = {0.75f, 0.75f, 0.75f, 1.0f}; shaderManager.UseStockShader(GLT_SHADER_DEFAULT_LIGHT, transformPipeline.GetModelViewMatrix(), transformPipeline.GetProjectionMatrix(), vGray); innerBatch.Draw(); // 出栈,还原为单位矩阵 modelViewMatrix.PopMatrix(); // 双缓存模式,后台缓存切换到前台进行显示 glutSwapBuffers(); } void SetupTubeBatch() { tubeBatch.Begin(GL_QUADS, 200); tubeBatch.Color4f(1.0f, 0.0f, 0.0f, 1.0f); // 后面 GLfloat vBack[] = { // Left Pannel -50.0f, 50.0f, fZ, -50.0f, -50.0f, fZ, -35.0f, -50.0f, fZ, -35.0f, 50.0f, fZ, // Right Panel 50.0f, 50.0f, fZ, 35.0f, 50.0f, fZ, 35.0f, -50.0f, fZ, 50.0f,-50.0f, fZ, // Top Panel -35.0f, 50.0f, fZ, -35.0f, 35.0f, fZ, 35.0f, 35.0f, fZ, 35.0f, 50.0f, fZ, // Bottom Panel -35.0f, -35.0f, fZ, -35.0f, -50.0f, fZ, 35.0f, -50.0f, fZ, 35.0f, -35.0f, fZ }; for (int i = 0; i < 16; i++) { int index = i * 3; tubeBatch.Normal3f(0.0f, 0.0f, 1.0f); tubeBatch.Vertex3f(vBack[index], vBack[index+1], vBack[index+2]); } // 前面 GLfloat vFront[] = { // Left Pannel -35.0f, 50.0f, bZ, -35.0f, -50.0f, bZ, -50.0f, -50.0f, bZ, -50.0f, 50.0f, bZ, // Right Panel 50.0f, -50.0f, bZ, 35.0f, -50.0f, bZ, 35.0f, 50.0f, bZ, 50.0f, 50.0f, bZ, // Top Panel 35.0f, 50.0f, bZ, 35.0f, 35.0f, bZ, -35.0f, 35.0f, bZ, -35.0f, 50.0f, bZ, // Bottom Panel 35.0f, -35.0f, bZ, 35.0f, -50.0f, bZ, -35.0f, -50.0f, bZ, -35.0f, -35.0f, bZ }; for(int i = 0; i < 16; i++) { int index = i * 3; tubeBatch.Normal3f(0.0f, 0.0f, -1.0f); tubeBatch.Vertex3f(vFront[index], vFront[index+1], vFront[index+2]); } // 上面 GLfloat vTop[] = { -50.0f, 50.0f, fZ, 50.0f, 50.0f, fZ, 50.0f, 50.0f, bZ, -50.0f, 50.0f, bZ }; for(int i = 0; i < 4; i++) { int index = i * 3; tubeBatch.Normal3f(0.0f, 1.0f, 0.0f); tubeBatch.Vertex3f(vTop[index], vTop[index+1], vTop[index+2]); } // 下面 GLfloat vBottom[] = { -50.0f, -50.0f, fZ, -50.0f, -50.0f, bZ, 50.0f, -50.0f, bZ, 50.0f, -50.0f, fZ }; for(int i = 0; i < 4; i++) { int index = i * 3; tubeBatch.Normal3f(0.0f, -1.0f, 0.0f); tubeBatch.Vertex3f(vBottom[index], vBottom[index+1], vBottom[index+2]); } // 左面 GLfloat vLeft[] = { 50.0f, 50.0f, fZ, 50.0f, -50.0f, fZ, 50.0f, -50.0f, bZ, 50.0f, 50.0f, bZ }; for(int i = 0; i < 4; i++) { int index = i * 3; tubeBatch.Normal3f(1.0f, 0.0f, 0.0f); tubeBatch.Vertex3f(vLeft[index], vLeft[index+1], vLeft[index+2]); } // 右面 GLfloat vRight[] = { -50.0f, 50.0f, fZ, -50.0f, 50.0f, bZ, -50.0f, -50.0f, bZ, -50.0f, -50.0f, fZ }; for(int i = 0; i < 4; i++) { int index = i * 3; tubeBatch.Normal3f(-1.0f, 0.0f, 0.0f); tubeBatch.Vertex3f(vRight[index], vRight[index+1], vRight[index+2]); } tubeBatch.End(); } void SetupInnerBatch() { innerBatch.Begin(GL_QUADS, 40); innerBatch.Color4f(0.75f, 0.75f, 0.75f, 1.0f); // 上面 GLfloat innerTop[] = { -35.0f, 35.0f, fZ, 35.0f, 35.0f, fZ, 35.0f, 35.0f, bZ, -35.0f, 35.0f, bZ }; for(int i = 0; i < 4; i++) { int index = i * 3; innerBatch.Normal3f(0.0f, -1.0f, 0.0f); innerBatch.Vertex3f(innerTop[index], innerTop[index+1], innerTop[index+2]); } // 下面 GLfloat innerBottom[] = { -35.0f, -35.0f, fZ, -35.0f, -35.0f, bZ, 35.0f, -35.0f, bZ, 35.0f, -35.0f, fZ }; for(int i = 0; i < 4; i++) { int index = i * 3; innerBatch.Normal3f(0.0f, 1.0f, 0.0f); innerBatch.Vertex3f(innerBottom[index], innerBottom[index+1], innerBottom[index+2]); } // 左面 GLfloat innerLeft[] = { 35.0f, 35.0f, fZ, 35.0f, -35.0f, fZ, 35.0f, -35.0f, bZ, 35.0f, 35.0f, bZ }; for(int i = 0; i < 4; i++) { int index = i * 3; innerBatch.Normal3f(-1.0f, 0.0f, 0.0f); innerBatch.Vertex3f(innerLeft[index], innerLeft[index+1], innerLeft[index+2]); } // 右面 GLfloat innerRight[] = { -35.0f, 35.0f, fZ, -35.0f, 35.0f, bZ, -35.0f, -35.0f, bZ, -35.0f, -35.0f, fZ }; for(int i = 0; i < 4; i++) { int index = i * 3; innerBatch.Normal3f(1.0f, 0.0f, 0.0f); innerBatch.Vertex3f(innerRight[index], innerRight[index+1], innerRight[index+2]); } innerBatch.End(); } // 程序初始化环境 void SetupRC() { // 设置背景颜色为淡蓝色 glClearColor(0.0f, 0.0f, 0.75f, 1.0f ); // 开启深度测试 glEnable(GL_DEPTH_TEST); // 着色器初始化 shaderManager.InitializeStockShaders(); // 创建长方体暴露在外面的红色面 SetupTubeBatch(); // 创建长方体里面的灰色面 SetupInnerBatch(); } void SpecialKeys(int key, int x, int y) { // 按下上、下、左、右方向键,对物体进行旋转,m3dDegToRad = 角度 -> 弧度 switch(key) { case GLUT_KEY_UP: // angle=-5, x=1, y=0, z=0 表示绕x轴正方向顺时针旋转(从x轴正方向看去) viewFrame.RotateWorld(m3dDegToRad(-5.0f), 1.0f, 0.0f, 0.0f); break; case GLUT_KEY_DOWN: // angle=5, x=1, y=0, z=0 表示绕x轴正方向逆时针旋转(从x轴正方向看去) viewFrame.RotateWorld(m3dDegToRad(5.0f), 1.0f, 0.0f, 0.0f); break; case GLUT_KEY_LEFT: // angle=-5, x=0, y=1, z=0 表示绕y轴正方向顺时针旋转(从y轴正方向看去) viewFrame.RotateWorld(m3dDegToRad(-5.0f), 0.0f, 1.0f, 0.0f); break; case GLUT_KEY_RIGHT: // angle=5, x=0, y=1, z=0 表示绕y轴正方向逆时针旋转(从y轴正方向看去) viewFrame.RotateWorld(m3dDegToRad(5.0f), 0.0f, 1.0f, 0.0f); break; } // 重写渲染窗口 glutPostRedisplay(); } // 窗口变化回调 void ChangeSize(int width, int height) { // 设置视口 glViewport(0, 0, width, height); // 设置正投影,(xMin, xMax, yMin, yMax, zMin, zMax) viewFrustum.SetOrthographic(-130.0f, 130.0f, -130.0f, 130.0f, -130.0f, 130.0f); // 获得到的正投影矩阵载入堆栈中 projectionMatrix.LoadMatrix(viewFrustum.GetProjectionMatrix()); // 变换管线,管理2个堆栈 transformPipeline.SetMatrixStacks(modelViewMatrix, projectionMatrix); } // 程序入口 int main(int argc, char* argv[]) { // 针对 Mac OS 设置工作目录路径 gltSetWorkingDirectory(argv[0]); // 初始化 GLUT glutInit(&argc, argv); // 初始化渲染模式 glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH | GLUT_STENCIL); // 初始化窗口大小 glutInitWindowSize(800, 720); // 创建窗口并命名 glutCreateWindow("Orthographic Projection Example"); // 检测驱动程序是否初始化成功 GLenum err = glewInit(); if (GLEW_OK != err) { fprintf(stderr, "GLEW Error: %s\n", glewGetErrorString(err)); return 1; } // 窗口大小改变回调函数设置 glutReshapeFunc(ChangeSize); // 特殊按键点击回调函数设置 glutSpecialFunc(SpecialKeys); // 窗口渲染回调函数设置 glutDisplayFunc(RenderScene); // 程序初始化环境 SetupRC(); // 主消息循环 glutMainLoop(); return 0; }
效果图如下所示: