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#include "rotrect.h"
#include "cfg.h"
#include "lzy.h"
#include <math.h>
static void
rotate(double *x, double *y, double angle)
{
const double s = sin(angle);
const double c = cos(angle);
const double ox = *x;
const double oy = *y;
*x = ox * c - oy * s;
*y = ox * s + oy * c;
}
Rect
rotrect_create(double width, double height, double angle)
{
double xs[4] = {
width / 2.0,
width / 2.0,
-width / 2.0,
-width / 2.0,
};
double ys[4] = {
-height / 2.0,
height / 2.0,
height / 2.0,
-height / 2.0,
};
for (int i = 0; i < 4; i++)
rotate(&xs[i], &ys[i], angle);
return (Rect){ xs[0], ys[0], xs[1], ys[1], xs[2], ys[2], xs[3], ys[3] };
}
void
rotrect_draw(Rect rect, double x, double y)
{
const int xs[4] = {
round(rect.x0 + x), round(rect.x1) + x,
round(rect.x2 + x), round(rect.x3) + x
};
const int ys[4] = {
round(rect.y0 + y), round(rect.y1) + y,
round(rect.y2 + y), round(rect.y3) + y,
};
(void)LZY_DrawLine(xs[0], ys[0], xs[1], ys[1]);
(void)LZY_DrawLine(xs[1], ys[1], xs[2], ys[2]);
(void)LZY_DrawLine(xs[2], ys[2], xs[3], ys[3]);
(void)LZY_DrawLine(xs[3], ys[3], xs[0], ys[0]);
}
void
rotrect(double x, double y, double width, double height, double angle)
{
rotrect_draw(rotrect_create(width, height, angle), x, y);
}
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