首页 > 代码库 > 33、插入一段大学学的计算机，正儿八经的计算机图形学
33、插入一段大学学的计算机，正儿八经的计算机图形学
1、breaseHam画圆算法
public void breasenCircle(int a,int b,int r) { int x0 = 0; int y0 = r; int y = y0; int x = x0; GL.Vertex2(x + a, y + b); double p = y * y - 2 * (r * r - (x + 1) * (x + 1)) + (y - 1) * (y - 1); while(x<=x0+(Math.Sqrt(2)/2)*r){ if (p > 0) { p = p + 4 * (x - y) + 10; x = x + 1; y = y - 1; GL.Vertex2(x+a, y+b); GL.Vertex2(y+a, x+b); GL.Vertex2(x+a,-y+b); GL.Vertex2(-y+a,x+b); GL.Vertex2(-x+a,-y+b); GL.Vertex2(-y+a,-x+b); GL.Vertex2(-x+a, y+b); GL.Vertex2(y+a, -x+b); } else { p = p + 4 * x + 6; x = x + 1; GL.Vertex2(x+a, y+b); GL.Vertex2(y+a, x+b); GL.Vertex2(x+a, -y+b); GL.Vertex2(-y+a, x+b); GL.Vertex2(-x+a, -y+b); GL.Vertex2(-y+a, -x+b); GL.Vertex2(-x+a, y+b); GL.Vertex2(y+a, -x+b); } } }
2、breaseHam画直线
public void Bresenhamline(int x0, int y0, int x1, int y1) { double dx = x1 - x0; double dy = y1 - y0; int x=x0; int y=y0; double b = (y0 * x1 - y1 * x0) / (x1 - x0); if (Math.Abs(dy / dx) <= 1) { double p = 2 * dx * y - 2 * dy * x - 2 * dy - 2 * b * dx + dx; while (Math.Abs(x1 - x) > 1) { if (p > 0) { x = x + 1; GL.Vertex2(x, y); p = p - 2 * dy; } else { x = x + 1; y = y + 1; p = p + 2 * dx - 2 * dy; GL.Vertex2(x, y); } } } else { double p = 2 * x * dy - 2 * dx * y + dy - 2 * dx + 2 * dx * b; while (Math.Abs(y1 - y) > 1) { if (p > 0) { y = y + 1; GL.Vertex2(x, y); p = p - 2 * dx; } else { x = x + 1; y = y + 1; GL.Vertex2(x,y); p = p + 2 * dy - 2 * dx; } } } }
3、中点画线算法
public void midLine(int x0,int y0,int x1,int y1) { double a = y0 - y1; double b = x1 - x0; int x = x0; int y = y0; GL.Vertex2(x,y); if (Math.Abs(a / b) < 1) { double d = 2 * a + b; while (x < x1) { if (d < 0) { x = x + 1; y = y + 1; GL.Vertex2(x, y); d = d + a + b; } else { x = x + 1; GL.Vertex2(x, y); d = d + 2 * a; } } } else { double d = a + 2 * b; while(y<y1){ if (d < 0) { y = y + 1; GL.Vertex2(x, y); d = d + 2 * b; } else { y = y + 1; x = x + 1; GL.Vertex2(x,y); d = d + 2 * a + 2 * b; } } } }
4、DDA画线算法
public void DDALine(int x0,int y0,int x1,int y1) { float dx, dy, y, k,x; dx = x1 - x0; dy = y1 - y0; k = dy / dx; y = y0; x = x0; if (k <= 1) { for (x = x0; x < x1; x++) { GL.Vertex2(x, Math.Floor(y + 0.5)); y = y + k; } } else { for (y = y0; y < y1; y++) { GL.Vertex2(Math.Floor(x + 0.5), y); x = x + 1 / k; } } }
二、直线和圆的绘制
private void glControl1_Paint(object sender, PaintEventArgs e) { if (!loaded) return; GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); GL.MatrixMode(MatrixMode.Modelview); GL.LoadIdentity(); GL.Color3(Color.Green); GL.Begin(BeginMode.Polygon); GL.Vertex2(1, 1); GL.Vertex2(20, 80); GL.Vertex2(30, 200); GL.Vertex2(50, 180); GL.Vertex2(60, 50); GL.End(); allPaint8(50, 160, Color.Green, Color.Red); //paintGraphy(); GL.End(); glControl1.SwapBuffers(); } //八联通递归填充算法 public void allPaint8(int x, int y, Color boundry, Color fillColor) { if (Getpixel(x, y).ToArgb() != fillColor.ToArgb() && Getpixel(x, y).ToArgb() == boundry.ToArgb()) { GL.Color3(fillColor); GL.Begin(BeginMode.Points); GL.Vertex2(x, y); GL.End(); allPaint8(x - 1, y - 1, boundry, fillColor); allPaint4(x, y - 1, boundry, fillColor); allPaint8(x + 1, y - 1, boundry, fillColor); allPaint8(x - 1, y, boundry, fillColor); allPaint4(x + 1, y, boundry, fillColor); allPaint4(x, y + 1, boundry, fillColor); allPaint8(x - 1, y + 1, boundry, fillColor); allPaint8(x + 1, y + 1, boundry, fillColor); } }
//四联通递归填充算法 public void allPaint4(int x,int y,Color boundry,Color fillColor) { if (Getpixel(x, y).ToArgb()!= fillColor.ToArgb() && Getpixel(x, y).ToArgb()==boundry.ToArgb()) { GL.Color3(fillColor); GL.Begin(BeginMode.Points); GL.Vertex2(x, y); GL.End(); allPaint4(x - 1, y,boundry,fillColor); allPaint4(x, y + 1, boundry, fillColor); allPaint4(x + 1, y, boundry, fillColor); allPaint4(x, y - 1, boundry, fillColor); } }
多边形扫描线填充： 填充之前的图像如上所示： 填充之后的图像如下所示： private void glControl1_Paint(object sender, PaintEventArgs e) { if (!loaded) return; GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); GL.MatrixMode(MatrixMode.Modelview); GL.LoadIdentity(); GL.Color3(Color.Green); GL.Begin(BeginMode.Points); GL.Vertex2(1, 1); GL.Vertex2(20, 80); GL.Vertex2(30, 200); GL.Vertex2(50, 180); GL.Vertex2(60, 50); GL.End(); paintGraphy(); GL.End(); glControl1.SwapBuffers(); } //多边形扫描线算法 public void paintGraphy() { NList nlist = new NList(1); GL.Vertex2(1, 1); GL.Vertex2(20, 80); nlist.Add(new Node(1, (20.0 - 1.0) / (80.0 - 1.0), 80)); GL.Vertex2(30, 200); nlist.Add(new Node(20, (30.0 - 20.0) / (200.0 - 80.0), 200)); GL.Vertex2(50, 180); nlist.Add(new Node(50, (50.0 - 30.0) / (180.0 - 200.0), 200)); GL.Vertex2(60, 50); nlist.Add(new Node(60, (60.0 - 50.0) / (50.0 - 180.0), 180)); nlist.Add(new Node(1, (60.0 - 1.0) / (50.0 - 1.0), 50)); double t = 0; for (int i = 1; i <= 200; i++) { List<Point> listPoint = new List<Point>(); for (int j = 0; j < nlist.myndL.Count; j++) { if (j == 0) { if (i > 1 && i <= nlist.myndL[0].ymax) { listPoint.Add(new Point(nlist.myndL[j].x + i*nlist.myndL[0].dx, i)); } } else if (j == 1) { if (i > 1 && i <= nlist.myndL[1].ymax) { listPoint.Add(new Point(nlist.myndL[0].x + i*nlist.myndL[1].dx, i)); } } else if (j == 2) { if (i > nlist.myndL[0].ymax && i <= nlist.myndL[j + 1].ymax) { t = i - nlist.myndL[0].ymax; listPoint.Add(new Point(nlist.myndL[j].x + t * nlist.myndL[j].dx, i)); } } else { double YMAX; if (j + 1 == nlist.myndL.Count) { YMAX = nlist.myndL[1].ymax; } else { YMAX=nlist.myndL[j + 1].ymax; } double valueJ_1 = Math.Min(YMAX, nlist.myndL[j].ymax); double valueUp = Math.Max(YMAX, nlist.myndL[j].ymax); if (i >valueJ_1 && i <= valueUp ) { t = i - valueJ_1; listPoint.Add(new Point(nlist.myndL[j].x + t * nlist.myndL[j].dx, i)); } } } if (listPoint.Count == 2) { Bresenhamline(listPoint[0].x, listPoint[0].y, listPoint[1].x, listPoint[1].y); } } }
1. 图形的二维旋转 using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using OpenTK.Graphics.OpenGL; namespace mywapp { public partial class Form1 : Form { bool loaded = false; public Form1() { InitializeComponent(); } private void glControl1_Load(object sender, EventArgs e) { loaded = true; GL.ClearColor(Color.White); SetupViewport(); } private void SetupViewport() { int w = glControl1.Width; int h = glControl1.Height; GL.MatrixMode(MatrixMode.Projection); GL.LoadIdentity(); GL.Ortho(0, w, 0, h, -1, 1); // Bottom-left corner pixel has coordinate (0, 0) GL.Viewport(0, 0, w, h); // Use all of the glControl painting area } private void glControl1_Paint(object sender, PaintEventArgs e) { if (!loaded) return; GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); GL.MatrixMode(MatrixMode.Modelview); GL.LoadIdentity(); GL.Color3(Color.Green); GL.Begin(BeginMode.LineLoop); GL.Vertex2(1, 1); GL.Vertex2(20, 80); GL.Vertex2(30, 200); GL.Vertex2(50, 180); GL.Vertex2(60, 50); List<Point> list = new List<Point>(); list.Add(new Point(1, 1)); list.Add(new Point(20,80)); list.Add(new Point(30,200)); list.Add(new Point(50, 180)); list.Add(new Point(60, 50)); List<Point> nlist = rotato2(-30, list); foreach (Point point in nlist) { GL.Vertex2(point.x,point.y); } GL.End(); glControl1.SwapBuffers(); } //二维旋转 private List<Point> rotato2(int angel, List<Point> points) { double o=(angel*Math.PI)/180.0; double[,] a = new double[,] { { Math.Cos(o), -Math.Sin(o) }, { Math.Sin(o), Math.Cos(o) } }; foreach (Point point in points) { point.x = a[0, 0] * point.x + a[0, 1] * point.y; point.y = a[1, 0] * point.x + a[1, 1] * point.y; } return points; }
二维平移 将原图形在x轴上向右平移80个单位像素，在y轴上向上平移20个单位像素 //二维平移 private List<Point> moveLocation(int x, int y, List<Point> points) { foreach (Point point in points) { point.x = point.x + x; point.y = point.y + y; } return points; }
二维缩放 将原图形放大了1.3倍之后，在x轴上向右平移了60个单位像素后，得到的图形： //二维缩放 private List<Point> changeSize2(double size, List<Point> points) { double[,] a = new double[,] { { size, 0 }, { 0, size } }; foreach (Point point in points) { point.x = a[0, 0] * point.x + a[0, 1] * point.y; point.y = a[1, 0] * point.x + a[1, 1] * point.y; } return points; }
最后是超级牛逼的贝塞尔曲线
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using OpenTK.Graphics.OpenGL; namespace mywapp { public partial class Form1 : Form { bool loaded = false; public Form1() { InitializeComponent(); } private void glControl1_Load(object sender, EventArgs e) { loaded = true; GL.ClearColor(Color.White); SetupViewport(); } private void SetupViewport() { int w = glControl1.Width; int h = glControl1.Height; GL.MatrixMode(MatrixMode.Projection); GL.LoadIdentity(); GL.Ortho(0, w, 0, h, -1, 1); // Bottom-left corner pixel has coordinate (0, 0) GL.Viewport(0, 0, w, h); // Use all of the glControl painting area } private void glControl1_Paint(object sender, PaintEventArgs e) { if (!loaded) return; GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit); GL.MatrixMode(MatrixMode.Modelview); GL.LoadIdentity(); GL.Color3(Color.Green); GL.Begin(BeginMode.Points); GL.Vertex2(10, 30); GL.Vertex2(40, 60); GL.Vertex2(70, 50); GL.Vertex2(120, 100); GL.End(); int[,] shuzu = new int[4, 2] { { 10, 30 }, { 40, 60 }, { 70, 50 }, { 120, 110 } }; drawBezierCurve(shuzu); glControl1.SwapBuffers(); } //Bezier画曲线算法 public void drawBezierCurve(int[,] shuzu) { int n = 0; if ((n = shuzu.GetLength(0)) < 2) return; for (double t = 0.0; t <= 1; t += 0.05 / n) { double[,] pshuzu = new double[1, 2] { { 0, 0 } }; computeP(shuzu, n - 1, t, pshuzu); GL.Color3(Color.Red); GL.Begin(BeginMode.Points); GL.Vertex2(pshuzu[0, 0], pshuzu[0, 1]); GL.End(); } } void computeP(int[,] pshuzu, int count, double u, double[,] p) { int i = 0; int k = 0; double[,] Pshuzu = new double[count + 1, 2]; for (i = 0; i <= count; i++) { Pshuzu[i, 0] = pshuzu[i, 0]; Pshuzu[i, 1] = pshuzu[i, 1]; } for (k = 1; k <= count; k++) { for (i = 0; i <= count - k; i++) { Pshuzu[i, 0] = ((1 - u) * Pshuzu[i, 0] + u * Pshuzu[i + 1, 0]); Pshuzu[i, 1] = ((1 - u) * Pshuzu[i, 1] + u * Pshuzu[i + 1, 1]); } } p[0, 0] = Pshuzu[0, 0]; p[0, 1] = Pshuzu[0, 1]; } } }
今天是2016年10月18号，今天心情超级不开心
33、插入一段大学学的计算机，正儿八经的计算机图形学
声明：以上内容来自用户投稿及互联网公开渠道收集整理发布，本网站不拥有所有权，未作人工编辑处理，也不承担相关法律责任，若内容有误或涉及侵权可进行投诉： 投诉/举报 工作人员会在5个工作日内联系你，一经查实，本站将立刻删除涉嫌侵权内容。