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绿色是GL_FILL  黑色边框是GL_LINE  启用了GL_POLYGONE_OFFSET_LINE  和 进行了glPolygoneOffset(-1.0,-1.0) 进行的多边形模式glPolygoneMode(GL_FRONT_AND_BACK, GL_LINE)渲染

贴花效果主要代码：

void DrawWireFramedBatch(GLBatch* pBatch){	// Draw the batch solid green	shaderManager.UseStockShader(GLT_SHADER_FLAT, transformPipeline.GetModelViewProjectionMatrix(), vGreen);	pBatch->Draw();	// Draw black outline	glPolygonOffset(-1.0f, -1.0f);      // Shift depth values	glEnable(GL_POLYGON_OFFSET_LINE);	// Draw lines antialiased	glEnable(GL_LINE_SMOOTH);	glEnable(GL_BLEND);	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);	// Draw black wireframe version of geometry	glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);	glLineWidth(2.5f);	shaderManager.UseStockShader(GLT_SHADER_FLAT, transformPipeline.GetModelViewProjectionMatrix(), vBlack);	pBatch->Draw();	// Put everything back the way we found it	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);	glDisable(GL_POLYGON_OFFSET_LINE);	glLineWidth(1.0f);	glDisable(GL_BLEND);	glDisable(GL_LINE_SMOOTH);}

// Primitieves.cpp// OpenGL SuperBible, Chapter 2// Demonstrates the 7 Geometric Primitives// Program by Richard S. Wright Jr.#pragma comment(lib, "gltools.lib")#include 
   
    	// OpenGL toolkit#include 
    
     #include 
     
      #include 
      
       #include 
       
        #include 
        
         #include 
         
          #ifdef __APPLE__#include 
          
           #else#define FREEGLUT_STATIC#include 
           
            #endif/// An assortment of needed classesGLShaderManager shaderManager;GLMatrixStack modelViewMatrix;GLMatrixStack projectionMatrix;GLFrame cameraFrame;GLFrame objectFrame;GLFrustum viewFrustum;GLBatch pointBatch;GLBatch lineBatch;GLBatch lineStripBatch;GLBatch lineLoopBatch;GLBatch triangleBatch;GLBatch triangleStripBatch;GLBatch triangleFanBatch;GLGeometryTransform transformPipeline;M3DMatrix44f shadowMatrix;GLfloat vGreen[] = { 0.0f, 1.0f, 0.0f, 1.0f };GLfloat vBlack[] = { 0.0f, 0.0f, 0.0f, 1.0f };// Keep track of effects stepint nStep = 0;///// This function does any needed initialization on the rendering context. // This is the first opportunity to do any OpenGL related tasks.void SetupRC(){ // Black background glClearColor(0.7f, 0.7f, 0.7f, 1.0f); shaderManager.InitializeStockShaders(); glEnable(GL_DEPTH_TEST); transformPipeline.SetMatrixStacks(modelViewMatrix, projectionMatrix); cameraFrame.MoveForward(-15.0f); // // Some points, more or less in the shape of Florida GLfloat vCoast[24][3] = { {2.80, 1.20, 0.0 }, {2.0, 1.20, 0.0 }, {2.0, 1.08, 0.0 }, {2.0, 1.08, 0.0 }, {0.0, 0.80, 0.0 }, {-.32, 0.40, 0.0 }, {-.48, 0.2, 0.0 }, {-.40, 0.0, 0.0 }, {-.60, -.40, 0.0 }, {-.80, -.80, 0.0 }, {-.80, -1.4, 0.0 }, {-.40, -1.60, 0.0 }, {0.0, -1.20, 0.0 }, { .2, -.80, 0.0 }, {.48, -.40, 0.0 }, {.52, -.20, 0.0 }, {.48, .20, 0.0 }, {.80, .40, 0.0 }, {1.20, .80, 0.0 }, {1.60, .60, 0.0 }, {2.0, .60, 0.0 }, {2.2, .80, 0.0 }, {2.40, 1.0, 0.0 }, {2.80, 1.0, 0.0 } }; // Load point batch pointBatch.Begin(GL_POINTS, 24); pointBatch.CopyVertexData3f(vCoast); pointBatch.End(); // Load as a bunch of line segments lineBatch.Begin(GL_LINES, 24); lineBatch.CopyVertexData3f(vCoast); lineBatch.End(); // Load as a single line segment lineStripBatch.Begin(GL_LINE_STRIP, 24); lineStripBatch.CopyVertexData3f(vCoast); lineStripBatch.End(); // Single line, connect first and last points lineLoopBatch.Begin(GL_LINE_LOOP, 24); lineLoopBatch.CopyVertexData3f(vCoast); lineLoopBatch.End(); // For Triangles, we'll make a Pyramid GLfloat vPyramid[12][3] = { -2.0f, 0.0f, -2.0f, 2.0f, 0.0f, -2.0f, 0.0f, 4.0f, 0.0f, 2.0f, 0.0f, -2.0f, 2.0f, 0.0f, 2.0f, 0.0f, 4.0f, 0.0f, 2.0f, 0.0f, 2.0f, -2.0f, 0.0f, 2.0f, 0.0f, 4.0f, 0.0f, -2.0f, 0.0f, 2.0f, -2.0f, 0.0f, -2.0f, 0.0f, 4.0f, 0.0f }; triangleBatch.Begin(GL_TRIANGLES, 12); triangleBatch.CopyVertexData3f(vPyramid); triangleBatch.End(); // For a Triangle fan, just a 6 sided hex. Raise the center up a bit GLfloat vPoints[100][3]; // Scratch array, more than we need int nVerts = 0; GLfloat r = 3.0f; vPoints[nVerts][0] = 0.0f; vPoints[nVerts][1] = 0.0f; vPoints[nVerts][2] = 0.0f; for (GLfloat angle = 0; angle < M3D_2PI; angle += M3D_2PI / 6.0f) { nVerts++; vPoints[nVerts][0] = float(cos(angle)) * r; vPoints[nVerts][1] = float(sin(angle)) * r; vPoints[nVerts][2] = -0.5f; } // Close the fan nVerts++; vPoints[nVerts][0] = r; vPoints[nVerts][1] = 0; vPoints[nVerts][2] = 0.0f; // Load it up triangleFanBatch.Begin(GL_TRIANGLE_FAN, 8); triangleFanBatch.CopyVertexData3f(vPoints); triangleFanBatch.End(); // For triangle strips, a little ring or cylinder segment int iCounter = 0; GLfloat radius = 3.0f; for (GLfloat angle = 0.0f; angle <= (2.0f*M3D_PI); angle += 0.3f) { GLfloat x = radius * sin(angle); GLfloat y = radius * cos(angle); // Specify the point and move the Z value up a little vPoints[iCounter][0] = x; vPoints[iCounter][1] = y; vPoints[iCounter][2] = -0.5; iCounter++; vPoints[iCounter][0] = x; vPoints[iCounter][1] = y; vPoints[iCounter][2] = 0.5; iCounter++; } // Close up the loop vPoints[iCounter][0] = vPoints[0][0]; vPoints[iCounter][1] = vPoints[0][1]; vPoints[iCounter][2] = -0.5; iCounter++; vPoints[iCounter][0] = vPoints[1][0]; vPoints[iCounter][1] = vPoints[1][1]; vPoints[iCounter][2] = 0.5; iCounter++; // Load the triangle strip triangleStripBatch.Begin(GL_TRIANGLE_STRIP, iCounter); triangleStripBatch.CopyVertexData3f(vPoints); triangleStripBatch.End();}/void DrawWireFramedBatch(GLBatch* pBatch){ // Draw the batch solid green shaderManager.UseStockShader(GLT_SHADER_FLAT, transformPipeline.GetModelViewProjectionMatrix(), vGreen); pBatch->Draw(); // Draw black outline glPolygonOffset(-1.0f, -1.0f); // Shift depth values glEnable(GL_POLYGON_OFFSET_LINE); // Draw lines antialiased glEnable(GL_LINE_SMOOTH); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); // Draw black wireframe version of geometry glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); glLineWidth(2.5f); shaderManager.UseStockShader(GLT_SHADER_FLAT, transformPipeline.GetModelViewProjectionMatrix(), vBlack); pBatch->Draw(); // Put everything back the way we found it glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); glDisable(GL_POLYGON_OFFSET_LINE); glLineWidth(1.0f); glDisable(GL_BLEND); glDisable(GL_LINE_SMOOTH);}///// Called to draw scenevoid RenderScene(void){ // Clear the window with current clearing color glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); modelViewMatrix.PushMatrix(); M3DMatrix44f mCamera; cameraFrame.GetCameraMatrix(mCamera); modelViewMatrix.MultMatrix(mCamera); M3DMatrix44f mObjectFrame; objectFrame.GetMatrix(mObjectFrame); modelViewMatrix.MultMatrix(mObjectFrame); shaderManager.UseStockShader(GLT_SHADER_FLAT, transformPipeline.GetModelViewProjectionMatrix(), vBlack); switch (nStep) { case 0: glPointSize(4.0f); pointBatch.Draw(); glPointSize(1.0f); break; case 1: glLineWidth(2.0f); lineBatch.Draw(); glLineWidth(1.0f); break; case 2: glLineWidth(2.0f); lineStripBatch.Draw(); glLineWidth(1.0f); break; case 3: glLineWidth(2.0f); lineLoopBatch.Draw(); glLineWidth(1.0f); break; case 4: DrawWireFramedBatch(&triangleBatch); break; case 5: DrawWireFramedBatch(&triangleStripBatch); break; case 6: DrawWireFramedBatch(&triangleFanBatch); break; } modelViewMatrix.PopMatrix(); // Flush drawing commands glutSwapBuffers();}// Respond to arrow keys by moving the camera frame of referencevoid SpecialKeys(int key, int x, int y){ if (key == GLUT_KEY_UP) objectFrame.RotateWorld(m3dDegToRad(-5.0f), 1.0f, 0.0f, 0.0f); if (key == GLUT_KEY_DOWN) objectFrame.RotateWorld(m3dDegToRad(5.0f), 1.0f, 0.0f, 0.0f); if (key == GLUT_KEY_LEFT) objectFrame.RotateWorld(m3dDegToRad(-5.0f), 0.0f, 1.0f, 0.0f); if (key == GLUT_KEY_RIGHT) objectFrame.RotateWorld(m3dDegToRad(5.0f), 0.0f, 1.0f, 0.0f); glutPostRedisplay();}///// A normal ASCII key has been pressed.// In this case, advance the scene when the space bar is pressedvoid KeyPressFunc(unsigned char key, int x, int y){ if (key == 32) { nStep++; if (nStep > 6) nStep = 0; } switch (nStep) { case 0: glutSetWindowTitle("GL_POINTS"); break; case 1: glutSetWindowTitle("GL_LINES"); break; case 2: glutSetWindowTitle("GL_LINE_STRIP"); break; case 3: glutSetWindowTitle("GL_LINE_LOOP"); break; case 4: glutSetWindowTitle("GL_TRIANGLES"); break; case 5: glutSetWindowTitle("GL_TRIANGLE_STRIP"); break; case 6: glutSetWindowTitle("GL_TRIANGLE_FAN"); break; } glutPostRedisplay();}///// Window has changed size, or has just been created. In either case, we need// to use the window dimensions to set the viewport and the projection matrix.void ChangeSize(int w, int h){ glViewport(0, 0, w, h); viewFrustum.SetPerspective(35.0f, float(w) / float(h), 1.0f, 500.0f); projectionMatrix.LoadMatrix(viewFrustum.GetProjectionMatrix()); modelViewMatrix.LoadIdentity();}///// Main entry point for GLUT based programsint main(int argc, char* argv[]){ gltSetWorkingDirectory(argv[0]); glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH | GLUT_STENCIL); glutInitWindowSize(800, 600); glutCreateWindow("GL_POINTS"); glutReshapeFunc(ChangeSize); glutKeyboardFunc(KeyPressFunc); glutSpecialFunc(SpecialKeys); glutDisplayFunc(RenderScene); GLenum err = glewInit(); if (GLEW_OK != err) { fprintf(stderr, "GLEW Error: %s\n", glewGetErrorString(err)); return 1; } SetupRC(); glutMainLoop(); return 0;}