Implementing basic physics

2022-11-29 16:34:42 +01:00
parent 3d3e264867
commit 1e04da963d
39 changed files with 1999 additions and 145 deletions
@@ -0,0 +1,105 @@
+#pragma once
+#include "Math/Vector.h"
+#include "Math/Matrix.h"
+#include "Containers/Array.h"
+
+namespace Seele
+{
+struct AABB
+{
+    Math::Vector min = Math::Vector(std::numeric_limits<float>::max());
+    Math::Vector max = Math::Vector(std::numeric_limits<float>::min());
+    float surfaceArea() const
+    {
+        Math::Vector d = max - min;
+        return 2.0f * (d.x * d.y + d.y * d.z + d.z * d.x);
+    }
+    bool intersects(const AABB& other) const
+    {
+        if (min.x > other.max.x
+         || max.x < other.min.x)
+        {
+            return false;
+        }
+        if (min.y > other.max.y
+         || max.y < other.min.y)
+        {
+            return false;
+        }
+        if (min.z > other.max.z
+         || max.z < other.min.z)
+        {
+            return false;
+        }
+        return true;
+    }
+    bool contains(const AABB& other) const
+    {
+        if (min.x > other.min.x
+         || max.x < other.max.x)
+        {
+            return false;
+        }
+        if (min.y > other.min.y
+         || max.y < other.max.y)
+        {
+            return false;
+        }
+        if (min.z > other.min.z
+         || max.z < other.max.z)
+        {
+            return false;
+        }
+        return true;
+    }
+    AABB getTransformedBox(const Math::Matrix4& matrix) const
+    {
+        StaticArray<Math::Vector, 8> corners;
+        corners[0] = Math::Vector(min.x, min.y, min.z);
+        corners[1] = Math::Vector(min.x, min.y, max.z);
+        corners[2] = Math::Vector(min.x, max.y, min.z);
+        corners[3] = Math::Vector(min.x, max.y, max.z);
+        corners[4] = Math::Vector(max.x, min.y, min.z);
+        corners[5] = Math::Vector(max.x, min.y, max.z);
+        corners[6] = Math::Vector(max.x, max.y, min.z);
+        corners[7] = Math::Vector(max.x, max.y, max.z);
+        Math::Vector tmin = Math::Vector(1, 1, 1) * std::numeric_limits<float>::max();
+        Math::Vector tmax = Math::Vector(1, 1, 1) * std::numeric_limits<float>::min();
+        for(int i = 0; i < 8; ++i)
+        {
+            Math::Vector transformed = matrix * Math::Vector4(corners[i], 1.0f);
+            tmin = Math::Vector(std::min(tmin.x, transformed.x), std::min(tmin.y, transformed.y), std::min(tmin.z, transformed.z));
+            tmax = Math::Vector(std::max(tmax.x, transformed.x), std::max(tmax.y, transformed.y), std::max(tmax.z, transformed.z));
+        }
+        return AABB {
+            .min = tmin,
+            .max = tmax,
+        };
+    }
+    void adjust(const Math::Vector vertex)
+    {
+        min.x = std::min(min.x, vertex.x);
+        min.y = std::min(min.y, vertex.y);
+        min.z = std::min(min.z, vertex.z);
+        
+        max.x = std::max(max.x, vertex.x);
+        max.y = std::max(max.y, vertex.y);
+        max.z = std::max(max.z, vertex.z);
+    }
+    AABB combine(const AABB& other) const
+    {
+        return AABB {
+            .min = Math::Vector(
+                std::min(min.x, other.min.x),
+                std::min(min.y, other.min.y),
+                std::min(min.z, other.min.z)
+            ),
+            .max = Math::Vector (
+                std::max(max.x, other.max.x),
+                std::max(max.y, other.max.y),
+                std::max(max.z, other.max.z)
+            ),
+        };
+    }
+};
+} // namespace Seele