如何旋轉90度的計算機繪圖

我在空白窗口中創建了兔子和鴨子圖像。我的計劃是顯示它兩次：一次自己和另一個像旋轉90度的圖像。我嘗試過第二次創建圖像，並通過更改值來改變圖像，但很困難，根本無法工作。需要使用哪些軸來旋轉平面中的圖像並以正確的方式完成。如何旋轉90度的計算機繪圖

void myInit(void){ 
     glClearColor(1.0, 1.0, 1.0, 0); // the background is white 
     glColor3f(0.0f, 0.0f, 0.0f); // set drawing color 
     gluOrtho2D(0.0, (GLdouble) screenWidth, 0.0, (GLdouble) screenHeight); 
    } 

void drawBunny(){ 
    glClear(GL_COLOR_BUFFER_BIT); 
    // draw the outline of box (bunny) 
    glLineWidth(2); 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(50,50); 
     glVertex2i(150,50); 
     glVertex2i(150,100); 
     glVertex2i(50,100); 

    glEnd(); 

    //draw bunny tail 
    glLineWidth(1); 
    glBegin(GL_LINE_STRIP); 
    glVertex2i(50,50); 
    glVertex2i(50,35);//2nd wider top/bottom 
    glVertex2i(70,35);//1st- shrink tail left/right 
    glVertex2i(70,50);//1st- shrink tail left/right 
    glEnd(); 

    // draw first ear 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(175,85); 
     glVertex2i(175,100); 
     glVertex2i(150,100); 
     glVertex2i(150,85); 
    glEnd(); 

    //draw second ear 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(175,70); 
     glVertex2i(175,100); 
     glVertex2i(150,100); 
     glVertex2i(150,70); 
    glEnd(); 

    // draw the head 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(150,100); 
     glVertex2i(150,110); 
     glVertex2i(125,110); 
     glVertex2i(125,100); 
    glEnd(); 

    // draw first feet 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(110,60); 
     glVertex2i(110,75); 
     glVertex2i(30,75); //decrease value increase feet 
     glVertex2i(30,60); 
    glEnd(); 

    //draw second feet 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(50,100); 
     glVertex2i(50,85); 
     glVertex2i(30,85); //decrease value increase feet 
     glVertex2i(30,100); 
    glEnd(); 

    //* draw eyes 
    glBegin(GL_LINE_LOOP); 
     glVertex2i(140,100); 
     glVertex2i(140,105); 
     glVertex2i(135,105); 
     glVertex2i(135,100); 
    glEnd(); 
    glFlush(); 
} 

int main (int argc, char** argv){ 
    glutInit(&argc, argv); // initialize the toolkit 
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); // set display mode 
    glutInitWindowPosition(100,150); // set window position 
    glutInitWindowSize(screenWidth,screenHeight); // set window size 
    glutCreateWindow("House"); // create & open window 
    glutDisplayFunc(drawBunny); // register redraw function 
    myInit(); 
    glutMainLoop(); // loop forever 
}

來源

2014-11-15 Ricardo Arteaga

寫其中包括2只兔子並將其旋轉顯示功能：

void display() 
{ 
    glLoadIdentity(); 
    glClear(GL_COLOR_BUFFER_BIT); 

    drawBunny(); 

    glPushMatrix(); 
    glRotatef(degreetoreturn,x,y,z); // Adjust parameters according to what you need 
    drawBunny(); 
    glPopMatrix(); 

    glutSwapBuffers(); 

}

刪除glClear()功能，並從drawBunny功能glFlush()功能。最後在主函數改變這一行：

glutDisplayFunc(drawBunny); // register redraw function

到

glutDisplayFunc(display); // register redraw function

來源

2014-11-15 14:16:47

** + 1個** - 一個小的點但是：'glutSwapBuffers（...）'是不是在這個正確的場景。像素格式是單緩衝的。雖然我不會建議首先使用單緩衝像素格式（'GLUT_SINGLE'），但這是我們在這裏的： - \ –

@ AndonM.Coleman感謝您的警告，我閱讀了您正確的文檔。在單緩衝情況下，此功能不起作用。 –

我昨晚玩完這一切後發現問題。轉換順序是問題。 glTranslatef（100，100，0）; glRotatef（180.0f，0.0f，0.0f，1.0f）; glScalef（-1.0f，1.0f，1.0f）; @Cagkan Toptas –

如何旋轉90度的計算機繪圖

回答

相關問題