1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/revol.cc	Sun Aug 23 05:37:09 2015 +0300
     1.3 @@ -0,0 +1,44 @@
     1.4 +#include <algorithm>
     1.5 +#include "revol.h"
     1.6 +
     1.7 +Vector2 bezier_revol(float u, float v, void *cls)
     1.8 +{
     1.9 +	BezCurve *curve = (BezCurve*)cls;
    1.10 +	int nseg = (curve->numcp - 1) / 2;
    1.11 +
    1.12 +	if(v >= 1.0) v = 1.0 - 1e-6;
    1.13 +	int cidx = std::min((int)(v * nseg), nseg - 1);
    1.14 +	float t = fmod(v * (float)nseg, 1.0);
    1.15 +
    1.16 +	const vec2_t *cp = curve->cp + cidx * 2;
    1.17 +
    1.18 +	float resx = bezier(cp[0].x, cp[1].x, cp[1].x, cp[2].x, t);
    1.19 +	float resy = bezier(cp[0].y, cp[1].y, cp[1].y, cp[2].y, t);
    1.20 +	return Vector2(resx * curve->scale, resy * curve->scale);
    1.21 +}
    1.22 +
    1.23 +Vector2 bezier_revol_normal(float u, float v, void *cls)
    1.24 +{
    1.25 +	BezCurve *curve = (BezCurve*)cls;
    1.26 +	int nseg = (curve->numcp - 1) / 2;
    1.27 +
    1.28 +	if(v >= 1.0) v = 1.0 - 1e-6;
    1.29 +	int cidx = std::min((int)(v * nseg), nseg - 1);
    1.30 +	float t = fmod(v * (float)nseg, 1.0);
    1.31 +
    1.32 +	const vec2_t *cp = curve->cp + cidx * 2;
    1.33 +	Vector2 cp0 = cp[0];
    1.34 +	Vector2 cp1 = cp[1];
    1.35 +	Vector2 cp2 = cp[2];
    1.36 +
    1.37 +	Vector2 pprev, pnext;
    1.38 +	for(int i=0; i<2; i++) {
    1.39 +		pprev[i] = bezier(cp0[i], cp1[i], cp1[i], cp2[i], t - 0.05);
    1.40 +		pnext[i] = bezier(cp0[i], cp1[i], cp1[i], cp2[i], t + 0.05);
    1.41 +	}
    1.42 +
    1.43 +	float tx = pnext.x - pprev.x;
    1.44 +	float ty = pnext.y - pprev.y;
    1.45 +
    1.46 +	return Vector2(-ty, tx);
    1.47 +}