c畫直線編程
⑴ 怎樣用C語言繪制直線
【C語言的用MoveTo()和LineTo()】
#include<graphics.h>
#include<math.h>
/*
###############################################################################
功 能：本函數的作用是用逐點比較法來畫一條直線
格 式：void myline1(int x1,int y1,int x2,int y2,int color)
參數說明：x1,y1是起始點坐標,x2,y2是終止點,color是畫線的顏色
調用示例：myline1(10,20,500,440,4)
###############################################################################
*/
void myline1(int x1,int y1,int x2,int y2,int color)
{
/*變數定義開始（2007/10/16增加）*/
int iTx; /*x軸終點的相對坐標xa或臨時變數*/
int iTy; /*y軸終點的相對坐標ya或臨時變數*/
int iDx; /*x軸方向的步長dx*/
int iDy; /*y軸方向的步長dy*/
int iFt; /*偏差Fm*/
int iSt; /*記數循環數(dx+dy)S*/
int iXt; /*x方向循環變數xm*/
int iYt; /*y方向循環變數ym*/
/*變數定義結束*/
/*變數初始化開始*/
/*如果是第三象限或第四象限則換成第一或第二象限*/
if(y2<y1)
{
iTx=x1;
x1=x2;
x2=iTx;
iTy=y1;
y1=y2;
y2=iTy;
}
iTx=x2-x1; /*取x軸的相對坐標*/
iTy=y2-y1; /*取y軸的相對坐標*/
iDx=1;
iDy=1;
iFt=0;
iSt=iTx+iTy;
if(iTx<0)iSt=-1*iTx+iTy;; /*如果在第二象限，則x軸方向步長取負值*/
iXt=0;
iYt=0;
/*變數初始化結束*/
/*數據處理開始*/
while(iSt>0)
{
putpixel(x1+iXt,y1+iYt,color);
if(iTx>=0) /*如果在第一象限*/
{
if(iFt<0) /*如果偏差小於0*/
{
iYt+=iDy; /*y方向走一步*/
iFt+=iTx;
}
else /*如果偏差大於或等於0*/
{
iXt+=iDx; /*x方向走一步*/
iFt-=iTy;
}
}
else
{
if(iFt<0) /*如果偏差小於0*/
{
iXt-=iDx; /*負x方向走一步*/
iFt+=iTy;
}
else /*如果偏差大於或等於0*/
{
iYt+=iDy; /*y方向走一步*/
iFt+=iTx;
}
}
iSt--;
}
}
/*
###############################################################################
功 能：本函數的作用是用來畫一條直線
格 式：void myline2(int x1,int y1,int x2,int y2,int color)
參數說明：x1,y1是起始點坐標,x2,y2是終止點,color是畫線的顏色
調用示例：myline2(10,20,500,440,4)
###############################################################################
*/
int myline2(int x1,int y1,int x2,int y2,int color)
{
int iX; /*x方向的坐標變數*/
int iY; /*y方向的坐標變數*/
int iTx; /*x方向的步長變數*/
int iTy; /*y方向的步長變數*/
float fDx; /*x方向的差分變數*/
float fDy; /*y方向的差分變數*/
float fMinf; /*演算法中的f*/
float fMaxF; /*演算法中的F*/
float fS; /*終點判斷變數*/
fMinf=0.5; /*f=0.5*/
iX=x1;
iY=y1;
putpixel(x1,y1,color);
if(x1==x2&&y1==y2) /*如果終點和起始點相同*/
{
return(1);
}
iTx=1;
iTy=1;
fDx=(float)(x2-x1);
fDy=(float)(y2-y1);
fMaxF=fDy/fDx>0?fDy/fDx:(-fDy/fDx); /*F=|dy/dx|*/
if(fDx<0)iTx=-1;
if(fDy<0)iTy=-1;
fS=fDx>0?fDx:(-fDx);
if(fMaxF==1) /*如果F=1*/
{
iX=x1;
iY=y1;
while(fS>0)
{
iX+=iTx; /*x方向走一步*/
iY+=iTy; /*y方向走一步*/
putpixel(iX,iY,color);
fS--;
}
}
else if(fMaxF>1) /*如果F>1*/
{
fS+=fDy>0?fDy:(-fDy);
while(fS>0)
{
iY+=iTy; /*y方向走一步*/
putpixel(iX,iY,color);
fMinf+=1/fMaxF; /*f=f+1/F*/
fS--;
if(fMinf>=1) /*如果f>=1*/
{
iX+=iTx; /*x方向走一步*/
fMinf--; /*f=f-1*/
putpixel(iX,iY,color);
fS--;
}
}
}
else /*如果F<1*/
{
fS+=fDy>0?fDy:(-fDy);
while(fS>0)
{
iX+=iTx; /*x方向走一步*/
putpixel(iX,iY,color);
fMinf+=fMaxF; /*f=f+F*/
fS--;
if(fMinf>=1) /*如果f>=1*/
{
iY+=iTy; /*y方向走一步*/
fMinf--; /*f=f-1*/
putpixel(iX,iY,color);
fS--;
}
}
}
}【能夠畫出任意斜率的直線演算法程序】
int dx,dy,incrE,incrNE,d,x,y;
if ((point[1].x-point[0].x)==0){ //垂直的直線
x=point[0].x;
for(y=point[0].y;y<point[1].y;y++)
pDC->SetPixel(x,y,50);
}
else if(abs((point[1].y-point[0].y)/(point[1].x-point[0].x))<=1){ //斜率 -1到 1 之間
dx=point[1].x-point[0].x;
dy=point[0].y-point[1].y;
d=dx-2*dy; incrE=-2*dy;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
if(point[0].y>point[1].y){
while(x<point[1].x)
{
if(d>=0){
d+=incrE;
x++;
}
else
{d+=incrNE;<br> x++;<br> y--;<br> }
pDC->SetPixel(x,y,50);
}
}
else if(point[0].y<=point[1].y){
dy=point[1].y-point[0].y;
incrE=-2*dy;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
while(x<point[1].x)
{
if(d>=0){
d+=incrE;
x++;
}
else
{d+=incrNE;<br> x++;<br> y++;<br> }
pDC->SetPixel(x,y,50);
}
}
}
else { //斜率 <-1 和 >1的直線
if(point[1].x>=point[0].x){
dx=point[1].x-point[0].x;
dy=point[1].y-point[0].y;
d=2*dx-dy;
incrE=2*dx;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
while(x<point[1].x)
{
if(d<0){
d+=incrE;
y++;
}
else
{d+=incrNE;<br> pDC->SetPixel(x,y,50);<br> x++;<br> y++;<br> }
pDC->SetPixel(x,y,50);
}
}
else if((point[1].y-point[0].y)/(point[1].x-point[0].x)<-1){
dx=point[1].x-point[0].x;
dy=point[0].y-point[1].y;
d=2*dx-dy;
incrE=2*dx;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
while(y<point[1].y)
{
if(d>0){
d+=incrE;
y++;
}
else
{d+=incrNE;<br> x--;<br> y++;<br> }
pDC->SetPixel(x,y,50);
} }
}
⑵ 利用C語言編寫 能夠畫出任意的直線演算法程序（利用畫點函數）
上次剛寫過，在VC下運行的，
int dx,dy,incrE,incrNE,d,x,y;
if ((point[1].x-point[0].x)==0){ //垂直的直線
x=point[0].x;
for(y=point[0].y;y<point[1].y;y++)
pDC->SetPixel(x,y,50);
}
else if(abs((point[1].y-point[0].y)/(point[1].x-point[0].x))<=1){ //斜率 -1到 1 之間
dx=point[1].x-point[0].x;
dy=point[0].y-point[1].y;
d=dx-2*dy;
incrE=-2*dy;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
if(point[0].y>point[1].y){
while(x<point[1].x)
{
if(d>=0){
d+=incrE;
x++;
}
else
{d+=incrNE;
x++;
y--;
}
pDC->SetPixel(x,y,50);
}
}
else if(point[0].y<=point[1].y){
dy=point[1].y-point[0].y;
incrE=-2*dy;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
while(x<point[1].x)
{
if(d>=0){
d+=incrE;
x++;
}
else
{d+=incrNE;
x++;
y++;
}
pDC->SetPixel(x,y,50);
}
}
}
else { //斜率 <-1 和 >1的直線
if(point[1].x>=point[0].x){
dx=point[1].x-point[0].x;
dy=point[1].y-point[0].y;
d=2*dx-dy;
incrE=2*dx;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
while(x<point[1].x)
{
if(d<0){
d+=incrE;
y++;
}
else
{d+=incrNE;
pDC->SetPixel(x,y,50);
x++;
y++;
}
pDC->SetPixel(x,y,50);
}
}
else if((point[1].y-point[0].y)/(point[1].x-point[0].x)<-1){
dx=point[1].x-point[0].x;
dy=point[0].y-point[1].y;
d=2*dx-dy;
incrE=2*dx;
incrNE=2*(dx-dy);
x=point[0].x,y=point[0].y;
pDC->SetPixel(x,y,50);
while(y<point[1].y)
{
if(d>0){
d+=incrE;
y++;
}
else
{d+=incrNE;
x--;
y++;
}
pDC->SetPixel(x,y,50);
}
}
}
⑶ C語言畫直線和填充的程序，要有演算法的
c 畫的指針式 Roma 表
#include <dos.h>
#include <stdio.h>
#include <math.h>
#include <graphics.h>
void drawhourbrick(int x, int y, int color, float arg);
void drawminutebrick(int x, int y, int color, float arg);
void drawsecondbrick(int x, int y, int color, float arg);
void polygon(int n, int x, int y, int r, int color, float arg, int fillstyle);
int main()
{
int GraphDriver;
int GraphMode;
float arg = 292.5;
float hourarg = 0;
float minuterarg = 0;
float secondrarg = 0;
char buffer[10];
int a, b;
int x, y, r;
int h;
int xmo[12] = {1, 2, -6, -1, -1, -2, -2, -1, 0, -4, -4, -5};
int ymo[12] = {-1, -2, -1, -1, -1, -5, 2, 1, -2, -4, -4, 0};
long delay;
float degree;
struct time time, time1;
GraphDriver = DETECT;
initgraph(&GraphDriver, &GraphMode, "");
x = 300;
y = 220;
r = 200;
degree = atan(1) / 45;
polygon(8, x, y, r, 12, arg, 0);
polygon(8, x, y, r - 2, 11, arg, 0);
polygon(8, x, y, r - 4, 14, arg, 0);
setcolor(12);
/*settextstyle(DEFAULT_FONT, 1, 0);*/
for (a = 0; a < 12; a++)
{
sprintf(buffer, "%d", a + 1);
outtextxy(x + (r - 22) * cos((a - 2) * 30 * degree) + xmo[a], y + (r - 22) * sin((a - 2) * 30 * degree) + ymo[a], buffer);
}
drawhourbrick(x, y, 14, hourarg);
drawminutebrick(x, y, 9, minuterarg);
drawsecondbrick(x, y, 13, secondrarg);
while(1)
{
gettime(&time);
if (time.ti_hour != time1.ti_hour || time.ti_min != time1.ti_min || time.ti_sec != time1.ti_sec)
{
h = time.ti_hour;
if (h > 12)
h -= 12;
drawhourbrick(x, y, 0, hourarg);
drawminutebrick(x, y, 0, minuterarg);
drawsecondbrick(x, y, 0, secondrarg);
hourarg = (h % 12) * 30 + time.ti_min * 0.5 + time.ti_sec * 0.1 / 60;
minuterarg = time.ti_min * 6 + time.ti_sec * 0.1;
secondrarg = time.ti_sec * 6;
setcolor(8);
outtextxy(x - 15, y + 120, "Roma");
drawhourbrick(x, y, 14, hourarg);
drawminutebrick(x, y, 9, minuterarg);
drawsecondbrick(x, y, 13, secondrarg);
time1 = time;
}
while(kbhit())
{
a = getch();
if (a == 27)
{
closegraph();
return 0;
}
}
}
}
void polygon(int n, int x, int y, int r, int color, float arg, int fillstyle)
{
double pi;
int i;
float x1[9], y1[9];
setcolor(color);
pi = atan(1) * 4;
arg = atan(1) / 45 * arg;
x1[1] = x + r * cos(2 * pi / n + arg);
y1[1] = y + r * sin(2 * pi / n + arg);
moveto(x1[1], y1[1]);
for (i = 2; i <= n; i++)
{
x1[i] = x + r * cos(2 * pi * i / n + arg);
y1[i] = y + r * sin(2 * pi * i / n + arg);
lineto(x1[i], y1[i]);
}
lineto(x1[1], y1[1]);
if (fillstyle != 0)
{
setfillstyle(SOLID_FILL, color);
floodfill(x, y, color);
}
}
void drawhourbrick(int x, int y, int color, float arg)
{
double pi;
int i;
float x1[4], y1[4];
setcolor(color);
pi = atan(1) / 45;
x1[0] = x;
y1[0] = y;
x1[1] = x + 20 * cos(pi * (arg - 90 - 23));
y1[1] = y + 20 * sin(pi * (arg - 90 - 23));
x1[2] = x + 25 * cos(pi * (arg - 90 + 23));
y1[2] = y + 25 * sin(pi * (arg - 90 + 23));
x1[3] = x + 120 * cos(pi * (arg - 90 + 0));
y1[3] = y + 120 * sin(pi * (arg - 90 + 0));
moveto(x1[1], y1[1]);
lineto(x1[0], y1[0]);
lineto(x1[2], y1[2]);
lineto(x1[3], y1[3]);
lineto(x1[1], y1[1]);
setfillstyle(SOLID_FILL, color);
/*
floodfill((x1[0] + x1[3]) / 2, (y1[0] + y1[3]) / 2, color);
*/
}
void drawminutebrick(int x, int y, int color, float arg)
{
double pi;
int i;
float x1[4], y1[4];
setcolor(color);
pi = atan(1) / 45;
x1[0] = x;
y1[0] = y;
x1[1] = x + 20 * cos(pi * (arg - 90 - 23));
y1[1] = y + 20 * sin(pi * (arg - 90 - 23));
x1[2] = x + 25 * cos(pi * (arg - 90 + 23));
y1[2] = y + 25 * sin(pi * (arg - 90 + 23));
x1[3] = x + 160 * cos(pi * (arg - 90 + 0));
y1[3] = y + 160 * sin(pi * (arg - 90 + 0));
moveto(x1[1], y1[1]);
lineto(x1[0], y1[0]);
lineto(x1[2], y1[2]);
lineto(x1[3], y1[3]);
lineto(x1[1], y1[1]);
setfillstyle(SOLID_FILL, color);
/*
floodfill((x1[0] + x1[3]) / 2, (y1[0] + y1[3]) / 2, color);
*/
}
void drawsecondbrick(int x, int y, int color, float arg)
{
double pi;
int i;
float x1[4], y1[4];
setcolor(color);
pi = atan(1) / 45;
x1[0] = x;
y1[0] = y;
x1[1] = x + 20 * cos(pi * (arg - 90 - 6));
y1[1] = y + 20 * sin(pi * (arg - 90 - 6));
x1[2] = x + 25 * cos(pi * (arg - 90 + 6));
y1[2] = y + 25 * sin(pi * (arg - 90 + 6));
x1[3] = x + 160 * cos(pi * (arg - 90 + 0));
y1[3] = y + 160 * sin(pi * (arg - 90 + 0));
moveto(x1[1], y1[1]);
lineto(x1[0], y1[0]);
lineto(x1[2], y1[2]);
lineto(x1[3], y1[3]);
lineto(x1[1], y1[1]);
setfillstyle(SOLID_FILL, color);
/*
floodfill((x1[0] + x1[3]) / 2, (y1[0] + y1[3]) / 2, color);
*/
}
⑷ c++如何畫直線
包含windows.h,裡面有一個SetPixel方法，畫線常用演算法有三種dda，中點畫線Bresenham畫線->_->
剛把三種都寫了下
voidCDDALineView::drawDDALine(CDC*pDC,intx0,inty0,intx1,inty1,COLORREFcolor)
{
floatdeltax,deltay,x,y;
intsteps=max(abs(x1-x0),abs(y1-y0));
deltax=(x1-x0)/steps;
deltay=(y1-y0)/steps;
x=x0;
y=y0;
pDC->SetPixel((int)(x+0.5),(int)(y+0.5),color);
for(inti=0;i<steps;i++)
{
x+=deltax;
y+=deltay;
pDC->SetPixel((int)(x+0.5),(int)(y+0.5),color);
}
}
//preCondition：x0<x1
voidCDDALineView::MidpointLine(CDC*pDC,intx0,inty0,intx1,inty1,COLORREFcolor)
{
inta=y0-y1;
intb=x1-x0;
intc=x0*y1-x1*y0;
floatd,d1,d2;
d=2*a+b;
d1=2*a;
d2=2*(a+b);
intx=x0,y=y0;
pDC->SetPixel(x,y,color);
while(x<x1)
{
if(d<0)
{
x++;
y++;
d+=d2;
}
else{
x++;
d+=d1;
}
pDC->SetPixel(x,y,color);
}
}
voidCDDALineView::BresenhamLine(CDC*pDC,intx0,inty0,intx1,inty1,COLORREFcolor)
{
intx,y,dx,dy;
dx=x1-x0;
dy=y1-y0;
floatk=dy/dx;
x=x0;
y=y0;
floate=-0.5;
for(inti=0;i<=dx;i++)
{
pDC->SetPixel(x,y,color);
x++;
e+=k;
if(e>=0)
{
y++;
e-=1;
}
}
}
僅供參考
⑸ 用C語言模擬畫圖行（直線、 橢圓形、 三角形、 矩形、 梯形）求寫編程
#include <stdio.h>
#define PI 3.14159
float erea_round(float r)
{
//圓形面積
return r * r * PI;
}
float erea_tri(float d,float h)
{
//三角形 面積棚畢
return 0.5 * d * h;
}
float erea_rec(float a,float b)
{
//矩形面積
return a * b;
}
int main()
{
float r,a,b,d,h;
int choose;
while (1)
{
printf("請選擇要計算的圖像:\n");
printf("1、圓形\n");
printf("2、三角形碧滾\n");
printf("3、矩形\n");
printf("4、退出\n");
scanf("%d",&choose);
if (choose == 1)
{
printf("請輸入圓的半徑:\n");
scanf("鏈慧芹%f",&r);
printf("該圓面積為：%.3f\n",erea_round(r));
}
else if (choose == 2)
{
printf("請輸入三角形的底和高:\n");
scanf("%f%f",&d,&h);
printf("該三角形面積為：%.3f\n",erea_tri(d,h));
}
else if (choose == 3)
{
printf("請輸入矩形的長和寬:\n");
scanf("%f%f",&a,&b);
printf("該矩形面積為：%.3f\n",erea_rec(a,b));
}
else return 0;
}
return 0;
}