godot/modules/lightmapper_rd/lightmapper_rd.h

#ifndef LIGHTMAPPER_RD_H
#define LIGHTMAPPER_RD_H

#include "core/local_vector.h"
#include "scene/3d/lightmapper.h"
#include "scene/resources/mesh.h"
#include "servers/rendering/rendering_device.h"

class LightmapperRD : public Lightmapper {
	GDCLASS(LightmapperRD, Lightmapper)

	struct MeshInstance {
		MeshData data;
		int slice = 0;
		Vector2i offset;
	};

	struct Light {
		float position[3];
		uint32_t type = LIGHT_TYPE_DIRECTIONAL;
		float direction[3];
		float energy;
		float color[3];
		float size;
		float range;
		float attenuation;
		float spot_angle;
		float spot_attenuation;
		uint32_t static_bake;
		uint32_t pad[3];

		bool operator<(const Light &p_light) const {
			return type < p_light.type;
		}
	};

	struct Vertex {
		float position[3];
		float normal_z;
		float uv[2];
		float normal_xy[2];

		bool operator==(const Vertex &p_vtx) const {
			return (position[0] == p_vtx.position[0]) &&
				   (position[1] == p_vtx.position[1]) &&
				   (position[2] == p_vtx.position[2]) &&
				   (uv[0] == p_vtx.uv[0]) &&
				   (uv[1] == p_vtx.uv[1]) &&
				   (normal_xy[0] == p_vtx.normal_xy[0]) &&
				   (normal_xy[1] == p_vtx.normal_xy[1]) &&
				   (normal_z == p_vtx.normal_z);
		}
	};

	struct Edge {
		Vector3 a;
		Vector3 b;
		Vector3 na;
		Vector3 nb;
		bool operator==(const Edge &p_seam) const {
			return a == p_seam.a && b == p_seam.b && na == p_seam.na && nb == p_seam.nb;
		}
		Edge() {
		}

		Edge(const Vector3 &p_a, const Vector3 &p_b, const Vector3 &p_na, const Vector3 &p_nb) {
			a = p_a;
			b = p_b;
			na = p_na;
			nb = p_nb;
		}
	};

	struct Probe {
		float position[4];
	};

	Vector<Probe> probe_positions;

	struct EdgeHash {
		_FORCE_INLINE_ static uint32_t hash(const Edge &p_edge) {
			uint32_t h = hash_djb2_one_float(p_edge.a.x);
			h = hash_djb2_one_float(p_edge.a.y, h);
			h = hash_djb2_one_float(p_edge.a.z, h);
			h = hash_djb2_one_float(p_edge.b.x, h);
			h = hash_djb2_one_float(p_edge.b.y, h);
			h = hash_djb2_one_float(p_edge.b.z, h);
			return h;
		}
	};
	struct EdgeUV2 {
		Vector2 a;
		Vector2 b;
		Vector2i indices;
		bool operator==(const EdgeUV2 &p_uv2) const {
			return a == p_uv2.a && b == p_uv2.b;
		}
		bool seam_found = false;
		EdgeUV2(Vector2 p_a, Vector2 p_b, Vector2i p_indices) {
			a = p_a;
			b = p_b;
			indices = p_indices;
		}
		EdgeUV2() {}
	};

	struct Seam {
		Vector2i a;
		Vector2i b;
		uint32_t slice;
		bool operator<(const Seam &p_seam) const {
			return slice < p_seam.slice;
		}
	};

	struct VertexHash {
		_FORCE_INLINE_ static uint32_t hash(const Vertex &p_vtx) {
			uint32_t h = hash_djb2_one_float(p_vtx.position[0]);
			h = hash_djb2_one_float(p_vtx.position[1], h);
			h = hash_djb2_one_float(p_vtx.position[2], h);
			h = hash_djb2_one_float(p_vtx.uv[0], h);
			h = hash_djb2_one_float(p_vtx.uv[1], h);
			h = hash_djb2_one_float(p_vtx.normal_xy[0], h);
			h = hash_djb2_one_float(p_vtx.normal_xy[1], h);
			h = hash_djb2_one_float(p_vtx.normal_z, h);
			return h;
		}
	};

	struct Box {
		float min_bounds[3];
		float pad0;
		float max_bounds[3];
		float pad1;
	};

	struct Triangle {
		uint32_t indices[3];
		uint32_t slice;
		bool operator<(const Triangle &p_triangle) const {
			return slice < p_triangle.slice;
		}
	};

	Vector<MeshInstance> mesh_instances;

	Vector<Light> lights;

	struct TriangleSort {
		uint32_t cell_index;
		uint32_t triangle_index;
		bool operator<(const TriangleSort &p_triangle_sort) const {
			return cell_index < p_triangle_sort.cell_index; //sorting by triangle index in this case makes no sense
		}
	};

	void _plot_triangle_into_triangle_index_list(int p_size, const Vector3i &p_ofs, const AABB &p_bounds, const Vector3 p_points[], uint32_t p_triangle_index, LocalVector<TriangleSort> &triangles, uint32_t p_grid_size);

	struct RasterPushConstant {
		float atlas_size[2];
		float uv_offset[2];
		float to_cell_size[3];
		uint32_t base_triangle;
		float to_cell_offset[3];
		float bias;
		int32_t grid_size[3];
		uint32_t pad2;
	};

	struct RasterSeamsPushConstant {

		uint32_t base_index;
		uint32_t slice;
		float uv_offset[2];
		uint32_t debug;
		float blend;
		uint32_t pad[2];
	};

	struct PushConstant {
		int32_t atlas_size[2];
		uint32_t ray_count;
		uint32_t ray_to;

		float world_size[3];
		float bias;

		float to_cell_offset[3];
		uint32_t ray_from;

		float to_cell_size[3];
		uint32_t light_count;

		int32_t grid_size;
		int32_t atlas_slice;
		int32_t region_ofs[2];

		float environment_xform[12];
	};

	Vector<Ref<Image>> bake_textures;
	Vector<Color> probe_values;

	BakeError _blit_meshes_into_atlas(int p_max_texture_size, Vector<Ref<Image>> &albedo_images, Vector<Ref<Image>> &emission_images, AABB &bounds, Size2i &atlas_size, int &atlas_slices, BakeStepFunc p_step_function, void *p_bake_userdata);
	void _create_acceleration_structures(RenderingDevice *rd, Size2i atlas_size, int atlas_slices, AABB &bounds, int grid_size, Vector<Probe> &probe_positions, GenerateProbes p_generate_probes, Vector<int> &slice_triangle_count, Vector<int> &slice_seam_count, RID &vertex_buffer, RID &triangle_buffer, RID &box_buffer, RID &lights_buffer, RID &triangle_cell_indices_buffer, RID &probe_positions_buffer, RID &grid_texture, RID &grid_texture_sdf, RID &seams_buffer, BakeStepFunc p_step_function, void *p_bake_userdata);
	void _raster_geometry(RenderingDevice *rd, Size2i atlas_size, int atlas_slices, int grid_size, AABB bounds, float p_bias, Vector<int> slice_triangle_count, RID position_tex, RID unocclude_tex, RID normal_tex, RID raster_depth_buffer, RID rasterize_shader, RID raster_base_uniform);

public:
	virtual void add_mesh(const MeshData &p_mesh);
	virtual void add_directional_light(bool p_static, const Vector3 &p_direction, const Color &p_color, float p_energy, float p_angular_distance);
	virtual void add_omni_light(bool p_static, const Vector3 &p_position, const Color &p_color, float p_energy, float p_range, float p_attenuation, float p_size);
	virtual void add_spot_light(bool p_static, const Vector3 &p_position, const Vector3 p_direction, const Color &p_color, float p_energy, float p_range, float p_attenuation, float p_spot_angle, float p_spot_attenuation, float p_size);
	virtual void add_probe(const Vector3 &p_position);
	virtual BakeError bake(BakeQuality p_quality, bool p_use_denoiser, int p_bounces, float p_bias, int p_max_texture_size, bool p_bake_sh, GenerateProbes p_generate_probes, const Ref<Image> &p_environment_panorama, const Basis &p_environment_transform, BakeStepFunc p_step_function = nullptr, void *p_bake_userdata = nullptr);

	int get_bake_texture_count() const;
	Ref<Image> get_bake_texture(int p_index) const;
	int get_bake_mesh_count() const;
	Variant get_bake_mesh_userdata(int p_index) const;
	Rect2 get_bake_mesh_uv_scale(int p_index) const;
	int get_bake_mesh_texture_slice(int p_index) const;
	int get_bake_probe_count() const;
	Vector3 get_bake_probe_point(int p_probe) const;
	Vector<Color> get_bake_probe_sh(int p_probe) const;

	LightmapperRD();
};

#endif // LIGHTMAPPER_H