Add AABB rendering support to DebugRenderer

Author: MStachowicz

source/Geometry/AABB.hpp

@@ -47,6 +47,7 @@ namespace Geometry
 
 		AABB2D() : min(0.f), max(0.f) {}
 		AABB2D(const glm::vec2& min, const glm::vec2& max) : min(min), max(max) {}
+		AABB2D(const glm::vec2& center, float half_size)   : min(center - glm::vec2(half_size)), max(center + glm::vec2(half_size)) {}
 		bool operator==(const AABB2D& other) const = default;
 
 		glm::vec2 size()   const { return max - min; }

source/OpenGL/DebugRenderer.cpp

@@ -140,6 +140,34 @@ namespace OpenGL
 		m_tri_mb.set_colour(p_colour);
 		m_tri_mb.add_triangle(p_triangle);
 	}
+	void DebugRenderer::add(const Geometry::AABB& p_AABB, const glm::vec4& p_colour, bool fill)
+	{
+		if (fill) add(Geometry::Cuboid(p_AABB.get_center(), p_AABB.get_size() * 0.5f), p_colour);
+
+		// Get the 8 corners of the AABB
+		auto min_x_min_y_max_z = glm::vec3(p_AABB.m_min.x, p_AABB.m_min.y, p_AABB.m_max.z);
+		auto min_x_max_y_min_z = glm::vec3(p_AABB.m_min.x, p_AABB.m_max.y, p_AABB.m_min.z);
+		auto min_x_max_y_max_z = glm::vec3(p_AABB.m_min.x, p_AABB.m_max.y, p_AABB.m_max.z);
+		auto max_x_min_y_min_z = glm::vec3(p_AABB.m_max.x, p_AABB.m_min.y, p_AABB.m_min.z);
+		auto max_x_min_y_max_z = glm::vec3(p_AABB.m_max.x, p_AABB.m_min.y, p_AABB.m_max.z);
+		auto max_x_max_y_min_z = glm::vec3(p_AABB.m_max.x, p_AABB.m_max.y, p_AABB.m_min.z);
+
+		// Bottom face edges
+		add(Geometry::LineSegment(p_AABB.m_min, max_x_min_y_min_z), p_colour);      // Bottom front edge
+		add(Geometry::LineSegment(max_x_min_y_min_z, max_x_max_y_min_z), p_colour); // Bottom right edge
+		add(Geometry::LineSegment(max_x_max_y_min_z, min_x_max_y_min_z), p_colour); // Bottom back edge
+		add(Geometry::LineSegment(min_x_max_y_min_z, p_AABB.m_min), p_colour);      // Bottom left edge
+		// Top face edges
+		add(Geometry::LineSegment(min_x_min_y_max_z, max_x_min_y_max_z), p_colour); // Top front edge
+		add(Geometry::LineSegment(max_x_min_y_max_z, p_AABB.m_max), p_colour);      // Top right edge
+		add(Geometry::LineSegment(p_AABB.m_max, min_x_max_y_max_z), p_colour);      // Top back edge
+		add(Geometry::LineSegment(min_x_max_y_max_z, min_x_min_y_max_z), p_colour); // Top left edge
+		// Vertical edges connecting bottom and top faces
+		add(Geometry::LineSegment(p_AABB.m_min, min_x_min_y_max_z), p_colour);      // Front left vertical edge
+		add(Geometry::LineSegment(max_x_min_y_min_z, max_x_min_y_max_z), p_colour); // Front right vertical edge
+		add(Geometry::LineSegment(max_x_max_y_min_z, p_AABB.m_max), p_colour);      // Back right vertical edge
+		add(Geometry::LineSegment(min_x_max_y_min_z, min_x_max_y_max_z), p_colour); // Back left vertical edge
+	}
 	void DebugRenderer::add_axes(const glm::vec3& p_point, float length)
 	{
 		float scale = 0.01f * length;

source/OpenGL/DebugRenderer.hpp

@@ -88,6 +88,7 @@ namespace OpenGL
 		static void add(const Geometry::Ray& p_ray,           const glm::vec4& p_colour = glm::vec4(1.f));
 		static void add(const Geometry::Sphere& p_sphere,     const glm::vec4& p_colour = glm::vec4(1.f), size_t subdivisions = m_debug_options.m_subdivisions);
 		static void add(const Geometry::Triangle& p_triangle, const glm::vec4& p_colour = glm::vec4(1.f));
+		static void add(const Geometry::AABB& p_AABB,         const glm::vec4& p_colour = glm::vec4(1.f), bool fill = false);
 
 		static void add_axes(const glm::vec3& p_point, float length = 1.f);
 	};