【OpenGL】OpenGL 2D平移与旋转

#include "stdafx.h"#include <windows.h>#include <glew.h>#include "glut.h"#include <stdlib.h>#include <math.h>#include <stdio.h>#include <string>#include "png.h"#include "zlib.h"#include <glfw3.h>#pragma comment(lib, "glut.lib")#pragma comment(lib, "glut32.lib")#pragma comment(lib, "libpng16.lib")#pragma comment(lib, "zlib.lib")#pragma comment (lib,"glew32d.lib")#pragma comment (lib,"glfw3.lib")#pragma comment (lib,"glfw3dll.lib")

平移：

GLfloat rtx = 0.0f, rty = 0.0f, rtz = 0.0f;GLfloat step = 0.05;GLfloat exp1 = 1e-3;void init(){glLoadIdentity();glClearColor(0.0, 0.0, 0.0, 0.0);}void draw(void){glClear(GL_COLOR_BUFFER_BIT);glPushMatrix();printf("%f %f %f\n", rtx, rty, rtz);glTranslatef(rtx, rty, rtz);glBegin(GL_QUADS);glColor3f(1.0f, 0.0f, 0.0f);glVertex2f(-0.5f, 0.5f);glColor3f(0.0f, 1.0f, 0.0f);glVertex2f(0.5f, 0.5f);glColor3f(0.0f, 0.0f, 1.0f);glVertex2f(0.5f, -0.5f);glColor3f(0.5f, 0.5f, 0.5f);glVertex2f(-0.5f, -0.5f);glEnd();glPopMatrix();glutSwapBuffers();}/* special key defined in glut#define GLUT_KEY_F1         1#define GLUT_KEY_F2         2#define GLUT_KEY_F3         3#define GLUT_KEY_F4         4#define GLUT_KEY_F5         5#define GLUT_KEY_F6         6#define GLUT_KEY_F7         7#define GLUT_KEY_F8         8#define GLUT_KEY_F9         9#define GLUT_KEY_F10            10#define GLUT_KEY_F11            11#define GLUT_KEY_F12            12#define GLUT_KEY_LEFT           100#define GLUT_KEY_UP         101#define GLUT_KEY_RIGHT          102#define GLUT_KEY_DOWN           103#define GLUT_KEY_PAGE_UP        104#define GLUT_KEY_PAGE_DOWN      105#define GLUT_KEY_HOME           106#define GLUT_KEY_END            107#define GLUT_KEY_INSERT         108*/void processKeyBoard(int key, int x, int y){switch (key){case GLUT_KEY_LEFT:if (rtx - step > -0.53)rtx -= step;break;case GLUT_KEY_RIGHT:if (rtx + step < 0.53)rtx += step;break;case GLUT_KEY_UP:if (rty + step < 0.53)rty += step;break;case GLUT_KEY_DOWN:if (rty - step > -0.53)rty -= step;break;default:break;}glutPostRedisplay();return;}int main(int argc, char *argv[]){glutInit(&argc, argv);glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE);glutInitWindowPosition(100, 100);glutInitWindowSize(600, 600);glutCreateWindow("test");init();glutDisplayFunc(draw);//glutIdleFunc(move);  glutSpecialFunc(processKeyBoard);glutMainLoop();return 0;}

旋转：

static GLfloat xRot = 0.0f;static GLfloat yRot = 0.0f;//确定多边形绕法的方向bool bWinding = true;void SetupRC(void) {//设置窗口背景颜色为黑色glClearColor(0.0f, 0.0f, 0.0f, 1.0f);}void ChangeSize(GLint w, GLint h) {if (h == 0) h = 1;glViewport(0, 0, w, h);glMatrixMode(GL_PROJECTION);glLoadIdentity();if (w <= h) {glOrtho(-100.0f, 100.0f * h / w, -100.0f, 100.0f * h / w, -100.0f, 100.0f);}else {glOrtho(-100.0f * w / h, 100.0f * w / h, -100.0f, 100.0f, -100.0f, 100.0f);}glMatrixMode(GL_MODELVIEW);glLoadIdentity();}//在窗口中绘制图形void RenderScene(void) {glClear(GL_COLOR_BUFFER_BIT);//旋转图形glPushMatrix();glRotatef(xRot, 1.0f, 0.0f, 0.0f);glRotatef(yRot, 0.0f, 1.0f, 0.0f);//设置点的大小以及线宽glPointSize(5.0f);glLineWidth(5.0f);//设置多边形绕法的方向是顺时针还是逆时针if (bWinding) {glFrontFace(GL_CW);}else {glFrontFace(GL_CCW);}//绘制三角形glBegin(GL_TRIANGLES);glColor3f(0.0f, 1.0f, 0.0f);glVertex3f(0.0f, 60.0f, 0.0f);glColor3f(1.0f, 0.0f, 0.0f);glVertex3f(-60.0f, -60.0f, 0.0f);glColor3f(0.0f, 0.0f, 1.0f);glVertex3f(60.0f, -60.0f, 0.0f);glEnd();glPopMatrix();glutSwapBuffers();}void SpecialKeys(GLint key, GLint x, GLint y) {switch (key){case GLUT_KEY_UP:xRot -= 5.0f;break;case GLUT_KEY_DOWN:xRot += 5.0f;break;case GLUT_KEY_LEFT:yRot -= 5.0f;break;case GLUT_KEY_RIGHT:yRot += 5.0f;break;default:break;}if (xRot > 356.0f) xRot = 0.0f;if (xRot < -1.0f)  xRot = 355.0f;if (yRot > 356.0f) yRot = 0.0f;if (yRot < -1.0f)  yRot = 355.0f;glutPostRedisplay();//重回窗口}void ProcessMenu(GLint value) {switch (value){case 1://修改多边形正面为填充模式glPolygonMode(GL_FRONT, GL_FILL);break;case 2:glPolygonMode(GL_FRONT, GL_LINE);break;case 3:glPolygonMode(GL_FRONT, GL_POINT);break;case 4:glPolygonMode(GL_FRONT, GL_FILL);break;case 5:glPolygonMode(GL_FRONT, GL_LINE);break;case 6:glPolygonMode(GL_FRONT, GL_POINT);break;case 7:glShadeModel(GL_FLAT);break;case 8:glShadeModel(GL_SMOOTH);break;case 9:bWinding = !bWinding;break;case 10://以线条的框架显示图glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);break;default:break;}}int main(int argc, char *argv[]) {GLint nModeMenu = 0;GLint nMainMenu = 0;GLint nColorMenu = 0;glutInit(&argc, argv);glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);glutCreateWindow("多边形演示");glutReshapeFunc(ChangeSize);glutSpecialFunc(SpecialKeys);glutDisplayFunc(RenderScene);//创建一个子菜单nModeMenu = glutCreateMenu(ProcessMenu);glutAddMenuEntry("正面多边形填充模式", 1);glutAddMenuEntry("正面线框模型", 2);glutAddMenuEntry("正面点模式", 3);glutAddMenuEntry("反面多边形填充模式", 1);glutAddMenuEntry("反面线框模型", 2);glutAddMenuEntry("反面点模式", 3);glutAddMenuEntry("线条框架", 10);//增加一个子菜单nColorMenu = glutCreateMenu(ProcessMenu);glutAddMenuEntry("平面明暗模式", 7);glutAddMenuEntry("光滑明暗模式", 8);//创建主菜单nMainMenu = glutCreateMenu(ProcessMenu);glutAddSubMenu("多边形模式", nModeMenu);glutAddSubMenu("颜色模式", nColorMenu);glutAddMenuEntry("改变绕法", 9);//将创建菜单与右键关联，即把菜单设置为右键弹出式菜单glutAttachMenu(GLUT_RIGHT_BUTTON);SetupRC();glutMainLoop();}