add UVFace

src/maths/UVFace.hpp

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <array>
+#include <glm/glm.hpp>
+
+#include "UVRegion.hpp"
+
+struct UVFace {
+    std::array<glm::vec2, 4> points;
+
+    UVFace(const UVRegion& region) {
+        points[0] = {region.u1, region.v1};
+        points[1] = {region.u2, region.v1};
+        points[2] = {region.u2, region.v2};
+        points[3] = {region.u1, region.v2};
+    }
+
+    template<int n>
+    inline void rotate(int times) {
+        int times = n % 4;
+        if (times < 0) {
+            times += 4;
+        }
+        std::array<glm::vec2, 4> temp = points;
+        points[0] = temp[times];
+        points[1] = temp[(times + 1) % 4];
+        points[2] = temp[(times + 2) % 4];
+        points[3] = temp[(times + 3) % 4];
+    }
+};