33 lines
866 B
Plaintext
33 lines
866 B
Plaintext
// single point rotation
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rotate :: (p: *Vec2s64, center: Vec2s64, angle: s64) {
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rad := cast(float64)angle * (PI / 180.0);
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// translate to center
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tx := p.x - center.x;
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ty := p.y - center.y;
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// apply rotation
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rx := cast(s64)(tx * cos(rad) - ty * sin(rad));
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ry := cast(s64)(tx * sin(rad) + ty * cos(rad));
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// translate back
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p.x = rx + center.x;
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p.y = ry + center.y;
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}
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// rotate n points
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rotate :: (pn: ..*Vec2s64, center: Vec2s64, angle: s64) {
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for pn {
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rotate(it, center, angle);
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}
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}
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// rotate 3 points via triangle struct
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rotate :: (t: *Triangle, center: Vec2s64, angle: s64) {
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rotate(*t.p1, *t.p2, *t.p3, center = center, angle = angle);
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}
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// rotate 4 points via quad struct
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rotate :: (q: *Quad, center: Vec2s64, angle: s64) {
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rotate(*q.p1, *q.p2, *q.p3, *q.p4, center = center, angle = angle);
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} |