1 files changed, 67 insertions, 0 deletions
diff --git a/scene.cpp b/scene.cpp
new file mode 100644
index 0000000..89f6f75
--- /dev/null
+++ b/scene.cpp
@@ -0,0 +1,67 @@
+#include "camera.hpp"
+#include "model.hpp"
+#include "scene.hpp"
+
+void update_scene(
+	Model_Scene& ms,
+	Device* dev,
+	const Camera& cam,
+	World& w
+) {
+	for (auto v : w.view<Transform, C_Model>()) {
+		auto& t = v.get<Transform>();
+		auto& m = v.get<C_Model>();
+		m.i->transform = t.mat;
+	}
+	ms.update(cam, dev);
+}
+
+std::pair<Entity_Id, int> scene_pick(
+	World& world,
+	const Camera& cam,
+	int w,
+	int h,
+	int mx,
+	int my
+) {
+	v2f uv = (2.0f * v2f(mx, my) - v2f(w, h)) / (float)h;
+	v4f e =
+		cam.get_proj().inverse() *
+		v4f(uv.x, uv.y, -1.0f, 1.0f);
+	e.z = -1.0f; e.w = 0.0f;
+	v4f d4 = cam.get_view().inverse() * e;
+	v3f d = v3f::normalised(v3f(d4.x, d4.y, d4.z));
+	const v3f& o = cam.position;
+	float t = INFINITY;
+	Entity_Id r1 = 0;
+	int r2 = -1;
+	for (auto v : world.view<C_Model>()) {
+		Model_Instance& inst = *v.get<C_Model>().i;
+		Model* m = inst.m;
+		int j;
+		for (j = 0; j < m->mesh_count; j++) {
+			AABB& b = inst.bounds[j];
+			v3f id = 1.0f / d;
+			v3f t1 = (b.min - o) * id;
+			v3f t2 = (b.max - o) * id;
+			float tmin = std::max(std::max(
+				std::min(t1.x, t2.x),
+				std::min(t1.y, t2.y)),
+				std::min(t1.z, t2.z)
+			);
+			float tmax = std::min(std::min(
+				std::max(t1.x, t2.x),
+				std::max(t1.y, t2.y)),
+				std::max(t1.z, t2.z)
+			);
+			if (tmax < 0.0f || tmin > tmax)
+				continue;
+			if (tmin < t) {
+				t = tmin;
+				r1 = v.entity();
+				r2 = j;
+			}
+		}
+	}
+	return { r1, r2 };
+}