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#pragma once
#include "Matrix.h"
#include <algorithm>
unsigned int codeKS(vec2 P, float minX, float minY, float maxX, float maxY) {
unsigned int code = 0;
if (P.x < minX) {
code += 1;
}
else if (P.x > maxX) {
code += 2;
}
if (P.y < minY) {
code += 4;
}
else if (P.y > maxY) {
code += 8;
}
return code;
}
bool clip(vec2 & A, vec2 & B, float minX, float minY, float maxX, float maxY) {
unsigned int codeA = codeKS(A, minX, minY, maxX, maxY);
unsigned int codeB = codeKS(B, minX, minY, maxX, maxY);
while (codeA | codeB) {
if (codeA & codeB) {
return false;
}
if (codeA == 0) {
std::swap(A, B);
std::swap(codeA, codeB);
}
if (codeA & 1) {
A.y = A.y + (B.y - A.y) * (minX - A.x) / (B.x - A.x);
A.x = minX;
}
else if (codeA & 2) {
A.y = A.y + (B.y - A.y) * (maxX - A.x) / (B.x - A.x);
A.x = maxX;
}
else if (codeA & 4) {
A.x = A.x + (B.x - A.x) * (minY - A.y) / (B.y - A.y);
A.y = minY;
}
else {
A.x = A.x + (B.x - A.x) * (maxY - A.y) / (B.y - A.y);
A.y = maxY;
}
codeA = codeKS(A, minX, minY, maxX, maxY);
}
return true;
}
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