3D软件渲染教程：星域

青旅半醒 2022-09-04 15:52 167阅读 0赞

# 添加Stars3D.java #

/**
     *
     * @author yangshuohao
     */
    public class Stars3D 
    {
        
        private final float m_spread;
        private final float m_speed;
        
        private final float m_starX[];
        private final float m_starY[];
        private final float m_starZ[];
        
        public Stars3D(int numStars,float spread,float speed)
        {
        
            m_spread=spread;
            m_speed=speed;
            
            m_starX=new float[numStars];
            m_starY=new float[numStars];
            m_starZ=new float[numStars];
    
            for(int i=0;i<m_starX.length;i++)
            {
        
                InitStar(i);
            }
        }
        
        private void InitStar(int i)
        {
        
            m_starX[i]=2 * ((float)Math.random()-0.5f)*m_spread;
            m_starY[i]=2 * ((float)Math.random()-0.5f)*m_spread;
            m_starZ[i]=((float)Math.random()+0.00001f)*m_spread;              
        }
    
        public void UpdateAndRender(Bitmap target,float delta)
        {
        
            target.Clear((byte)0x00);
            
            float halfWidth=target.GetWidth()/2.0f;
            float halfHeight=target.GetHeight()/2.0f;
    
            for(int i=0;i<m_starX.length;i++)
            {
        
                m_starZ[i]-=delta*m_speed;
                
                if(m_starZ[i] <=0 )
                {
        
                    InitStar(i);
                }
                
                int x=(int)((m_starX[i]/m_starZ[i])*halfWidth+halfWidth);
                int y=(int)((m_starY[i]/m_starZ[i])*halfHeight+halfHeight);
    
                if(x<0 || x>=target.GetWidth() || (y<0 || y>=target.GetHeight()))
                {
        
                    InitStar(i);
                }
                else
                {
        
                    target.DrawPixel(x, y, (byte)0xff, (byte)0xff, (byte)0xff, (byte)0xff);
                }
            }
        }
    }

# 修改Display.java #

import java.awt.Canvas;
    import java.awt.Graphics;
    import java.awt.Dimension;
    import java.awt.image.BufferedImage;
    import java.awt.image.BufferStrategy;
    import java.awt.image.DataBufferByte;
    import javax.swing.JFrame;
    /**
     *
     * @author yangshuohao
     */
    public class Display extends Canvas
    {
        
        private final JFrame m_frame;
        private final Bitmap m_frameBuffer;
        private final BufferedImage m_displayImage;
        private final byte[] m_displayComponents;
        private final BufferStrategy m_bufferStrategy;
        private final Graphics m_grGraphics;
        
        public Bitmap GetFrameBuffer() {
         return m_frameBuffer; }
        
        public Display(int width,int height,String title)
        {
        
            Dimension size=new Dimension(width,height);
            setPreferredSize(size);
            setMinimumSize(size);
            setMaximumSize(size);
            
            m_frameBuffer=new Bitmap(width,height);
            m_displayImage=new BufferedImage(width,height,BufferedImage.TYPE_3BYTE_BGR);
            m_displayComponents=((DataBufferByte)m_displayImage.getRaster().getDataBuffer()).getData();
            
            m_frameBuffer.Clear((byte)0x80);
            for(int i=0;i<100;i++)
            {
        
                m_frameBuffer.DrawPixel(100+i, 100+i, (byte)0x00, (byte)0x00, (byte)0x00, (byte)0xff);
            }
            
            m_frame=new JFrame();
            m_frame.add(this);
            m_frame.pack();
            m_frame.setResizable(false);
            m_frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            m_frame.setLocationRelativeTo(null);
            m_frame.setTitle(title);
            m_frame.setVisible(true);
            
            createBufferStrategy(1);
            m_bufferStrategy=getBufferStrategy();
            m_grGraphics=m_bufferStrategy.getDrawGraphics();
        }
        
        public void SwapBuffers()
        {
        
            m_frameBuffer.CopyToByteArray(m_displayComponents);
            m_grGraphics.drawImage(m_displayImage, 0, 0, m_frameBuffer.GetWidth()
            ,m_frameBuffer.GetHeight(),null);
            m_bufferStrategy.show();
        }
    }

# 修改Main.java #

/**
     *
     * @author yangshuohao
     */
    public class Main 
    {
        
         public static void main(String[] args) 
        {
        
            
            Display display=new Display(800,660,"Render");
            Bitmap target=display.GetFrameBuffer();
            Stars3D stars=new Stars3D(4096,64.0f,20.0f);
            
            long previousTime=System.nanoTime();
            while (true)
            {
                    
                long currentTime=System.nanoTime();
                float delta=(float)((currentTime-previousTime)/1000000000.0);
                previousTime=currentTime;
                
                stars.UpdateAndRender(target, delta);
                display.SwapBuffers();
            }
        }
    }

# 结果 #

![在这里插入图片描述][7bf69cd640e04a5c93be8a3431e1b03a.gif_pic_center]

[7bf69cd640e04a5c93be8a3431e1b03a.gif_pic_center]: /images/20220829/5238f0b60e014eac9ace48bacfa9f5ca.png