OpenGL 顶点数组的使用

#include<GL/glut.h>

#include<stdlib.h>

#include<stdio.h>

#ifdefGL_VERSION_1_1

#definePOINTER1

#defineINTERLEAVED2

#defineDRAWARRAY1

#defineARRAYELEMENT2

#defineDRAWELEMENTS3

intsetupMethod=POINTER;

intderefMethod=DRAWARRAY;

voidsetupPointers(void)

{

//definevertices

staticGLintvertices[]={25,25,

100,325,

175,25,

175,325,

250,25,

325,325};

//definecolors

staticGLfloatcolors[]={1.0,0.2,0.2,

0.2,0.2,1.0,

0.8,1.0,0.2,

0.75,0.75,0.75,

0.35,0.35,0.35,

0.5,0.5,0.5};

//enableanddisablearraysrespectively

glEnableClientState(GL_VERTEX_ARRAY);

glEnableClientState(GL_COLOR_ARRAY);

//setthearrayofvertex

glVertexPointer(2,GL_INT,0,vertices);

//setthearrayofcolors

glColorPointer(3,GL_FLOAT,0,colors);

}

voidsetupInterleave(void)

{

staticGLfloatintertwined[]=

{1.0,0.2,1.0,100.0,100.0,0.0,

1.0,0.2,0.2,0.0,200.0,0.0,

1.0,1.0,0.2,100.0,300.0,0.0,

0.2,1.0,0.2,200.0,300.0,0.0,

0.2,1.0,1.0,300.0,200.0,0.0,

0.2,0.2,1.0,200.0,100.0,0.0};

//Specifyafewvertexarrayatthesametime

glInterleavedArrays(GL_C3F_V3F,0,intertwined);

}

voidinit(void)

{

glClearColor(0.0,0.0,0.0,0.0);

glShadeModel(GL_SMOOTH);

setupPointers();

}

voiddisplay(void)

{

glClear(GL_COLOR_BUFFER_BIT);

if(derefMethod==DRAWARRAY)

glDrawArrays(GL_TRIANGLES,0,6);

elseif(derefMethod==ARRAYELEMENT){

glBegin(GL_TRIANGLES);

glArrayElement(2);

glArrayElement(3);

glArrayElement(5);

glEnd();

}

elseif(derefMethod==DRAWELEMENTS){

GLuintindices[4]={0,1,3,4};

glDrawElements(GL_POLYGON,4,GL_UNSIGNED_INT,indices);

}

glFlush();

}

voidreshape(intw,inth)

{

glViewport(0,0,(GLsizei)w,(GLsizei)h);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

gluOrtho2D(0.0,(GLdouble)w,0.0,(GLdouble)h);

}

voidmouse(intbutton,intstate,intx,inty)

{

switch(button){

caseGLUT_LEFT_BUTTON:

if(state==GLUT_DOWN){

if(setupMethod==POINTER){

setupMethod=INTERLEAVED;

setupInterleave();

}

elseif(setupMethod==INTERLEAVED){

setupMethod=POINTER;

setupPointers();

}

glutPostRedisplay();

}

break;

caseGLUT_MIDDLE_BUTTON:

caseGLUT_RIGHT_BUTTON:

if(state==GLUT_DOWN){

if(derefMethod==DRAWARRAY)

derefMethod=ARRAYELEMENT;

elseif(derefMethod==ARRAYELEMENT)

derefMethod=DRAWELEMENTS;

elseif(derefMethod==DRAWELEMENTS)

derefMethod=DRAWARRAY;

glutPostRedisplay();

}

break;

default:

break;

}

}

voidkeyboard(unsignedcharkey,intx,inty)

{

switch(key){

case27:

exit(0);

break;

}

}

intmain(intargc,char**argv)

{

glutInit(&argc,argv);

glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);

glutInitWindowSize(350,350);

glutInitWindowPosition(100,100);

glutCreateWindow(argv[0]);

init();

glutDisplayFunc(display);

glutReshapeFunc(reshape);

glutMouseFunc(mouse);

glutKeyboardFunc(keyboard);

glutMainLoop();

return0;

}

#else

intmain(intargc,char**argv)

{

fprintf(stderr,"ThisprogramdemonstratesafeaturewhichisnotinOpenGLVersion1.0.\n");

fprintf(stderr,"IfyourimplementationofOpenGLVersion1.0hastherightextensions,\n");

fprintf(stderr,"youmaybeabletomodifythisprogramtomakeitrun.\n");

return0;

}

glEnableClientState(GL_VERTEX_ARRAY);//启用顶点数组

glEnableClientState(GL_COLOR_ARRAY);//启用颜色数组

glVertexPointer(2,GL_INT,0,vertices);//指定顶点数组

glColorPointer(3,GL_FLOAT,0,colors);//指定颜色数组

glInterleavedArrays(GL_C3F_V3F,0,intertwined);//颜色，顶点会存到一个数组中，数组混用。

glDrawArrays(GL_TRIANGLES,0,6);//顶点数组方式绘制

glArrayElement(2);//指定顶点数组元素方式绘制

glDrawElements（）；//顶点数组索引方式绘制