/* WIN-TC BGI 圖形編程模板 */

#include "Conio.h"
#include "graphics.h"
#include "Math.h"
#define closegr closegraph
#define PI 3.1415926

typedef struct triangle {
    int x[3];
    int y[3];
} triangle;

void initgr(void) /* BGI初始化 */
{
  int gd = DETECT, gm = 0; /* 和gd = VGA,gm = VGAHI是同樣效果 */
  registerbgidriver(EGAVGA_driver);/* 注冊BGI驅動后可以不需要.BGI文件的支持運行 */
  initgraph(&gd, &gm, "");
}

void printTriangle(triangle* pTri, int color)
{
    int i;
    setcolor(color);
    moveto(319 + pTri->x[0], 239 - pTri->y[0]);
    for (i = 1; i < 3; i++) {
        lineto(319 + pTri->x[i], 239 - pTri->y[i]);
    }
    lineto(319 + pTri->x[0], 239 - pTri->y[0]);
}

void move_a(triangle* pTri, float x, float y)
{
    int i;
    for (i = 0; i < 3; i++) {
        pTri->x[i] += x;
        pTri->y[i] += y;
    }
}

void move_b(triangle* pTri, double angle)
{
    int i;
    angle = angle * (PI / 180);
    for (i = 0; i < 3; i++) {
        pTri->x[i] = pTri->x[i]*cos(angle) - pTri->y[i]*sin(angle);
        pTri->y[i] = pTri->x[i]*sin(angle) + pTri->y[i]*cos(angle);
    }
}

void move_c(triangle* pTri, int multiX, int multiY)
{
    int i;
    for (i = 0; i < 3; i++) {
        pTri->x[i] *= multiX;
        pTri->y[i] *= multiY;
    }
}



int main(void)
{
    triangle tri = {20, 50, 30, 10, 30, 45};
  initgr(); /* BGI初始化 */
  setcolor(1);
  line(0, 239, 640, 239);
  line(319, 0, 319, 480);
  printTriangle(&tri, 5);
  move_a(&tri, 100, 50);
  printTriangle(&tri, 8);
  move_b(&tri, 30);
  printTriangle(&tri, 10);
  move_c(&tri, 2, 1);
  printTriangle(&tri, 12);

    

  getch(); /* 暫停一下，看看前面繪圖代碼的運行結果 */
  closegr(); /* 恢復TEXT屏幕模式 */
  return 0;
}