TeaPot
現在將介紹如何產生如下的視窗. 使用上下左右及滑鼠可以翻轉茶壺的角度
代碼如下
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tao.FreeGlut;
using Tao.OpenGl;
namespace TeaPot
{
class Program
{
static float d = 3f;
static float X = 0.0f;// Translate screen to x direction (left or right)
static float Y = 0.0f;// Translate screen to y direction (up or down)
static float Z = 0.0f;// Translate screen to z direction (zoom in or out)
static float rotX = 0.0f;// Rotate screen on x axis
static float rotY = 0.0f;// Rotate screen on y axis
static float rotZ = 0.0f;// Rotate screen on z axis
static float rotLx = 0.0f;// Translate screen by using the glulookAt function (left or right)
static float rotLy = 0.0f;// Translate screen by using the glulookAt function (up or down)
static float rotLz = 0.0f;// Translate screen by using the glulookAt function (zoom in or out)
static bool lines = true;// Display x,y,z lines (coordinate lines)
static bool rotation = false;// Rotate if F2 is pressed
static int old_x, old_y;// Used for mouse event
static int mousePressed;
static void drawings()
{
// Clear the Color Buffer and Depth Buffer
Gl.glClear(Gl.GL_COLOR_BUFFER_BIT | Gl.GL_DEPTH_BUFFER_BIT);
Gl.glPushMatrix();//push the Matrix before calling glRotatef and glTranslatef
Gl.glRotatef(rotX, 1.0f, 0.0f, 0.0f);//Rotate on x
Gl.glRotatef(rotY, 0.0f, 1.0f, 0.0f);//Rotate on y
Gl.glRotatef(rotZ, 0.0f, 0.0f, 1.0f);//Rotate on z
if (rotation)//If F2 is pressed update x,y,z for rotation of the teapot
{
rotX += 0.2f;
rotY += 0.2f;
rotZ += 0.2f;
}
Gl.glTranslatef(X, Y, Z);//Translates the screen left,right,up,down, and zoom
if (lines)//If F1 is pressed don't draw the lines
{
// Draw the positive side of the lines x,y,z
Gl.glBegin(Gl.GL_LINES);
Gl.glColor3f(0.0f, 1.0f, 0.0f); // Green for x axis
Gl.glVertex3f(0f, 0f, 0f);
Gl.glVertex3f(10f, 0f, 0f);
Gl.glColor3f(1.0f, 0.0f, 0.0f); // Red for y axis
Gl.glVertex3f(0f, 0f, 0f);
Gl.glVertex3f(0f, 10f, 0f);
Gl.glColor3f(0.0f, 0.0f, 1.0f); // Blue for z axis
Gl.glVertex3f(0f, 0f, 0f);
Gl.glVertex3f(0f, 0f, 10f);
Gl.glEnd();
// Dotted lines for the negative sides of x,y,z coordinates
Gl.glEnable(Gl.GL_LINE_STIPPLE);//Enable dotted pattern lines
Gl.glLineStipple(1, 0x0101);// Dotted stipple pattern for the lines
Gl.glBegin(Gl.GL_LINES);
Gl.glColor3f(0.0f, 1.0f, 0.0f);// Green for x axis
Gl.glVertex3f(-10f, 0f, 0f);
Gl.glVertex3f(0f, 0f, 0f);
Gl.glColor3f(1.0f, 0.0f, 0.0f);// Red for y axis
Gl.glVertex3f(0f, 0f, 0f);
Gl.glVertex3f(0f, -10f, 0f);
Gl.glColor3f(0.0f, 0.0f, 1.0f);// Blue for z axis
Gl.glVertex3f(0f, 0f, 0f);
Gl.glVertex3f(0f, 0f, -10f);
Gl.glEnd();
}
Glu.gluLookAt(0, 0, 0, 0, 0, 1, 0, 1, 0);
Glut.glutSolidTeapot(1);
Gl.glDisable(Gl.GL_LINE_STIPPLE);//Disable the line stipple
Glut.glutPostRedisplay();//Redraw the scene
Gl.glPopMatrix();//Don't forget to pop the Matrix
Glut.glutSwapBuffers();
}
static void init()
{
Gl.glShadeModel(Gl.GL_SMOOTH);//Set the shading model to smooth
//Clear the Color and Depth Buffer
Gl.glClear(Gl.GL_COLOR_BUFFER_BIT | Gl.GL_DEPTH_BUFFER_BIT);
Gl.glEnable(Gl.GL_LIGHTING);
Gl.glEnable(Gl.GL_LIGHT0);
float[] light_pos = new float[3] { 1, 0.5F, 1 };
Gl.glLightfv(Gl.GL_LIGHT0, Gl.GL_POSITION, light_pos);
Gl.glClearDepth(1.0f);//Set the Depth buffer value (ranges[0,1])
Gl.glEnable(Gl.GL_DEPTH_TEST);//Enable Depth test
Gl.glDepthFunc(Gl.GL_LEQUAL);//If two objects on the same coordinate show the first drawn
Gl.glClearColor(0, 0.8f, 0.8f, 1);
Gl.glHint(Gl.GL_PERSPECTIVE_CORRECTION_HINT, Gl.GL_NICEST);
}
static void reshape(int w, int h)
{
Gl.glViewport(0, 0, w, h);//Set the viewport
Gl.glMatrixMode(Gl.GL_PROJECTION);//Set the Matrix mode
Gl.glLoadIdentity();
Glu.gluPerspective(75f, (float)w / (float)h, 0.10f, 500.0f);
Gl.glMatrixMode(Gl.GL_MODELVIEW);
Gl.glLoadIdentity();
Glu.gluLookAt(rotLx, rotLy, d +
rotLz, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
}
public static void keyboard(byte key, int x, int y)
{
switch (key)
{
case 111://o Resets all parameters
case 80://O
rotation = false;
X = Y = 0.0f;
Z = 0.0f;
rotX = 0.0f;
rotY = 0.0f;
rotZ = 0.0f;
rotLx = 0.0f;
rotLy = 0.0f;
rotLz = 0.0f;
Gl.glMatrixMode(Gl.GL_MODELVIEW);
Gl.glLoadIdentity();
Glu.gluLookAt(rotLx, rotLy, d + rotLz,
0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);
break;
}
Glut.glutPostRedisplay();// Redraw the scene
}
private static void specialKey(int key, int x, int y)
{
switch (key)
{
case Glut.GLUT_KEY_LEFT://Rotate on y axis
rotY -= 2.0f;
break;
case Glut.GLUT_KEY_RIGHT://Rotate on y axis
rotY += 2.0f;
break;
case Glut.GLUT_KEY_UP://Rotate on x axis
rotX -= 2.0f;
break;
case Glut.GLUT_KEY_DOWN://Rotate on x axis
rotX += 2.0f;
break;
case Glut.GLUT_KEY_PAGE_UP://Rotate on z axis
rotZ -= 2.0f;
break;
case Glut.GLUT_KEY_PAGE_DOWN://Rotate on z axis
rotZ += 2.0f;
break;
case Glut.GLUT_KEY_F1://Enable/Disable coordinate lines
lines = !lines;
break;
case Glut.GLUT_KEY_F2://Enable/Disable automatic rotation
rotation = !rotation;
break;
default:
break;
}
Glut.glutPostRedisplay();
}
static void processMouseActiveMotion(int button, int state, int x, int y)
{
mousePressed = button;//Capture which mouse button is down
old_x = x;//Capture the x value
old_y = y;//Capture the y value
}
static void processMouse(int x, int y)
{
if ((mousePressed == 0))//If left mouse button is pressed
{
rotY = (x - old_x);
rotX = (y - old_y);
}
Glut.glutPostRedisplay();
}
static void processMouseWheel(int wheel, int direction, int x, int y)
{
Z += direction;
Glut.glutPostRedisplay();
}
static void Main(string[] args)
{
Glut.glutInit();// Initialize glut
// Setup display mode to double buffer and RGB color
Glut.glutInitDisplayMode(Glut.GLUT_DOUBLE | Glut.GLUT_RGB);
// Set the screen size
Glut.glutInitWindowSize(1024, 768);
Glut.glutCreateWindow("OpenGL 3D TeaPot With Tao");
init();
Glut.glutReshapeFunc(reshape);
Glut.glutDisplayFunc(drawings);
// Set window's key callback
Glut.glutKeyboardFunc(new Glut.KeyboardCallback(keyboard));
// Set window's to specialKey callback
Glut.glutSpecialFunc(new Glut.SpecialCallback(specialKey));
// Set window's to Mouse callback
Glut.glutMouseFunc(new Glut.MouseCallback(processMouseActiveMotion));
// Set window's to motion callback
Glut.glutMotionFunc(new Glut.MotionCallback(processMouse));
// Set window's to mouse motion callback
Glut.glutMouseWheelFunc(new Glut.MouseWheelCallback(processMouseWheel));
Glut.glutMainLoop();
}
}
}