/*************************************************************************/
/*  rasterizer_scene_gles3.h                                             */
/*************************************************************************/
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/*                           GODOT ENGINE                                */
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/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
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#ifndef RASTERIZERSCENEGLES3_H
#define RASTERIZERSCENEGLES3_H

/* Must come before shaders or the Windows build fails... */
#include "rasterizer_storage_gles3.h"

#include "drivers/gles3/shaders/cube_to_dp.glsl.gen.h"
#include "drivers/gles3/shaders/effect_blur.glsl.gen.h"
#include "drivers/gles3/shaders/exposure.glsl.gen.h"
#include "drivers/gles3/shaders/resolve.glsl.gen.h"
#include "drivers/gles3/shaders/scene.glsl.gen.h"
#include "drivers/gles3/shaders/screen_space_reflection.glsl.gen.h"
#include "drivers/gles3/shaders/ssao.glsl.gen.h"
#include "drivers/gles3/shaders/ssao_blur.glsl.gen.h"
#include "drivers/gles3/shaders/ssao_minify.glsl.gen.h"
#include "drivers/gles3/shaders/subsurf_scattering.glsl.gen.h"
#include "drivers/gles3/shaders/tonemap.glsl.gen.h"

class RasterizerSceneGLES3 : public RasterizerScene {
public:
	enum ShadowFilterMode {
		SHADOW_FILTER_NEAREST,
		SHADOW_FILTER_PCF5,
		SHADOW_FILTER_PCF13,
	};

	ShadowFilterMode shadow_filter_mode;

	uint64_t shadow_atlas_realloc_tolerance_msec;

	enum SubSurfaceScatterQuality {
		SSS_QUALITY_LOW,
		SSS_QUALITY_MEDIUM,
		SSS_QUALITY_HIGH,
	};

	SubSurfaceScatterQuality subsurface_scatter_quality;
	float subsurface_scatter_size;
	bool subsurface_scatter_follow_surface;
	bool subsurface_scatter_weight_samples;

	uint64_t render_pass;
	uint64_t scene_pass;
	uint32_t current_material_index;
	uint32_t current_geometry_index;

	RID default_material;
	RID default_material_twosided;
	RID default_shader;
	RID default_shader_twosided;

	RID default_worldcoord_material;
	RID default_worldcoord_material_twosided;
	RID default_worldcoord_shader;
	RID default_worldcoord_shader_twosided;

	RID default_overdraw_material;
	RID default_overdraw_shader;

	RasterizerStorageGLES3 *storage;

	Vector<RasterizerStorageGLES3::RenderTarget::Exposure> exposure_shrink;
	int exposure_shrink_size;

	struct State {

		bool texscreen_copied;
		int current_blend_mode;
		float current_line_width;
		int current_depth_draw;
		bool current_depth_test;
		GLuint current_main_tex;

		SceneShaderGLES3 scene_shader;
		CubeToDpShaderGLES3 cube_to_dp_shader;
		ResolveShaderGLES3 resolve_shader;
		ScreenSpaceReflectionShaderGLES3 ssr_shader;
		EffectBlurShaderGLES3 effect_blur_shader;
		SubsurfScatteringShaderGLES3 sss_shader;
		SsaoMinifyShaderGLES3 ssao_minify_shader;
		SsaoShaderGLES3 ssao_shader;
		SsaoBlurShaderGLES3 ssao_blur_shader;
		ExposureShaderGLES3 exposure_shader;
		TonemapShaderGLES3 tonemap_shader;

		struct SceneDataUBO {
			//this is a std140 compatible struct. Please read the OpenGL 3.3 Specificaiton spec before doing any changes
			float projection_matrix[16];
			float inv_projection_matrix[16];
			float camera_inverse_matrix[16];
			float camera_matrix[16];
			float ambient_light_color[4];
			float bg_color[4];
			float fog_color_enabled[4];
			float fog_sun_color_amount[4];

			float ambient_energy;
			float bg_energy;
			float z_offset;
			float z_slope_scale;
			float shadow_dual_paraboloid_render_zfar;
			float shadow_dual_paraboloid_render_side;
			float viewport_size[2];
			float screen_pixel_size[2];
			float shadow_atlas_pixel_size[2];
			float shadow_directional_pixel_size[2];

			float time;
			float z_far;
			float reflection_multiplier;
			float subsurface_scatter_width;
			float ambient_occlusion_affect_light;

			uint32_t fog_depth_enabled;
			float fog_depth_begin;
			float fog_depth_curve;
			uint32_t fog_transmit_enabled;
			float fog_transmit_curve;
			uint32_t fog_height_enabled;
			float fog_height_min;
			float fog_height_max;
			float fog_height_curve;
			// make sure this struct is padded to be a multiple of 16 bytes for webgl

		} ubo_data;

		GLuint scene_ubo;

		struct EnvironmentRadianceUBO {

			float transform[16];
			float ambient_contribution;
			uint8_t padding[12];

		} env_radiance_data;

		GLuint env_radiance_ubo;

		GLuint sky_verts;
		GLuint sky_array;

		GLuint directional_ubo;

		GLuint spot_array_ubo;
		GLuint omni_array_ubo;
		GLuint reflection_array_ubo;

		GLuint immediate_buffer;
		GLuint immediate_array;

		uint32_t ubo_light_size;
		uint8_t *spot_array_tmp;
		uint8_t *omni_array_tmp;
		uint8_t *reflection_array_tmp;

		int max_ubo_lights;
		int max_forward_lights_per_object;
		int max_ubo_reflections;
		int max_skeleton_bones;

		bool used_contact_shadows;

		int spot_light_count;
		int omni_light_count;
		int directional_light_count;
		int reflection_probe_count;

		bool cull_front;
		bool cull_disabled;
		bool used_sss;
		bool used_screen_texture;
		bool using_contact_shadows;

		VS::ViewportDebugDraw debug_draw;
	} state;

	/* SHADOW ATLAS API */

	struct ShadowAtlas : public RID_Data {

		enum {
			QUADRANT_SHIFT = 27,
			SHADOW_INDEX_MASK = (1 << QUADRANT_SHIFT) - 1,
			SHADOW_INVALID = 0xFFFFFFFF
		};

		struct Quadrant {

			uint32_t subdivision;

			struct Shadow {
				RID owner;
				uint64_t version;
				uint64_t alloc_tick;

				Shadow() {
					version = 0;
					alloc_tick = 0;
				}
			};

			Vector<Shadow> shadows;

			Quadrant() {
				subdivision = 0; //not in use
			}

		} quadrants[4];

		int size_order[4];
		uint32_t smallest_subdiv;

		int size;

		GLuint fbo;
		GLuint depth;

		Map<RID, uint32_t> shadow_owners;
	};

	struct ShadowCubeMap {

		GLuint fbo_id[6];
		GLuint cubemap;
		uint32_t size;
	};

	Vector<ShadowCubeMap> shadow_cubemaps;

	RID_Owner<ShadowAtlas> shadow_atlas_owner;

	RID shadow_atlas_create();
	void shadow_atlas_set_size(RID p_atlas, int p_size);
	void shadow_atlas_set_quadrant_subdivision(RID p_atlas, int p_quadrant, int p_subdivision);
	bool _shadow_atlas_find_shadow(ShadowAtlas *shadow_atlas, int *p_in_quadrants, int p_quadrant_count, int p_current_subdiv, uint64_t p_tick, int &r_quadrant, int &r_shadow);
	bool shadow_atlas_update_light(RID p_atlas, RID p_light_intance, float p_coverage, uint64_t p_light_version);

	struct DirectionalShadow {
		GLuint fbo;
		GLuint depth;
		int light_count;
		int size;
		int current_light;
	} directional_shadow;

	virtual int get_directional_light_shadow_size(RID p_light_intance);
	virtual void set_directional_shadow_count(int p_count);

	/* REFLECTION PROBE ATLAS API */

	struct ReflectionAtlas : public RID_Data {

		int subdiv;
		int size;

		struct Reflection {
			RID owner;
			uint64_t last_frame;
		};

		GLuint fbo[6];
		GLuint color;

		Vector<Reflection> reflections;
	};

	mutable RID_Owner<ReflectionAtlas> reflection_atlas_owner;

	virtual RID reflection_atlas_create();
	virtual void reflection_atlas_set_size(RID p_ref_atlas, int p_size);
	virtual void reflection_atlas_set_subdivision(RID p_ref_atlas, int p_subdiv);

	/* REFLECTION CUBEMAPS */

	struct ReflectionCubeMap {

		GLuint fbo_id[6];
		GLuint cubemap;
		GLuint depth;
		int size;
	};

	Vector<ReflectionCubeMap> reflection_cubemaps;

	/* REFLECTION PROBE INSTANCE */

	struct ReflectionProbeInstance : public RID_Data {

		RasterizerStorageGLES3::ReflectionProbe *probe_ptr;
		RID probe;
		RID self;
		RID atlas;

		int reflection_atlas_index;

		int render_step;

		uint64_t last_pass;
		int reflection_index;

		Transform transform;
	};

	struct ReflectionProbeDataUBO {

		float box_extents[4];
		float box_ofs[4];
		float params[4]; // intensity, 0, 0, boxproject
		float ambient[4]; //color, probe contrib
		float atlas_clamp[4];
		float local_matrix[16]; //up to here for spot and omni, rest is for directional
		//notes: for ambientblend, use distance to edge to blend between already existing global environment
	};

	mutable RID_Owner<ReflectionProbeInstance> reflection_probe_instance_owner;

	virtual RID reflection_probe_instance_create(RID p_probe);
	virtual void reflection_probe_instance_set_transform(RID p_instance, const Transform &p_transform);
	virtual void reflection_probe_release_atlas_index(RID p_instance);
	virtual bool reflection_probe_instance_needs_redraw(RID p_instance);
	virtual bool reflection_probe_instance_has_reflection(RID p_instance);
	virtual bool reflection_probe_instance_begin_render(RID p_instance, RID p_reflection_atlas);
	virtual bool reflection_probe_instance_postprocess_step(RID p_instance);

	/* ENVIRONMENT API */

	struct Environment : public RID_Data {

		VS::EnvironmentBG bg_mode;

		RID sky;
		float sky_custom_fov;

		Color bg_color;
		float bg_energy;
		float sky_ambient;

		Color ambient_color;
		float ambient_energy;
		float ambient_sky_contribution;

		int canvas_max_layer;

		bool ssr_enabled;
		int ssr_max_steps;
		float ssr_fade_in;
		float ssr_fade_out;
		float ssr_depth_tolerance;
		bool ssr_roughness;

		bool ssao_enabled;
		float ssao_intensity;
		float ssao_radius;
		float ssao_intensity2;
		float ssao_radius2;
		float ssao_bias;
		float ssao_light_affect;
		Color ssao_color;
		VS::EnvironmentSSAOQuality ssao_quality;
		float ssao_bilateral_sharpness;
		VS::EnvironmentSSAOBlur ssao_filter;

		bool glow_enabled;
		int glow_levels;
		float glow_intensity;
		float glow_strength;
		float glow_bloom;
		VS::EnvironmentGlowBlendMode glow_blend_mode;
		float glow_hdr_bleed_threshold;
		float glow_hdr_bleed_scale;
		bool glow_bicubic_upscale;

		VS::EnvironmentToneMapper tone_mapper;
		float tone_mapper_exposure;
		float tone_mapper_exposure_white;
		bool auto_exposure;
		float auto_exposure_speed;
		float auto_exposure_min;
		float auto_exposure_max;
		float auto_exposure_grey;

		bool dof_blur_far_enabled;
		float dof_blur_far_distance;
		float dof_blur_far_transition;
		float dof_blur_far_amount;
		VS::EnvironmentDOFBlurQuality dof_blur_far_quality;

		bool dof_blur_near_enabled;
		float dof_blur_near_distance;
		float dof_blur_near_transition;
		float dof_blur_near_amount;
		VS::EnvironmentDOFBlurQuality dof_blur_near_quality;

		bool adjustments_enabled;
		float adjustments_brightness;
		float adjustments_contrast;
		float adjustments_saturation;
		RID color_correction;

		bool fog_enabled;
		Color fog_color;
		Color fog_sun_color;
		float fog_sun_amount;

		bool fog_depth_enabled;
		float fog_depth_begin;
		float fog_depth_curve;
		bool fog_transmit_enabled;
		float fog_transmit_curve;
		bool fog_height_enabled;
		float fog_height_min;
		float fog_height_max;
		float fog_height_curve;

		Environment() {
			bg_mode = VS::ENV_BG_CLEAR_COLOR;
			sky_custom_fov = 0.0;
			bg_energy = 1.0;
			sky_ambient = 0;
			ambient_energy = 1.0;
			ambient_sky_contribution = 0.0;
			canvas_max_layer = 0;

			ssr_enabled = false;
			ssr_max_steps = 64;
			ssr_fade_in = 0.15;
			ssr_fade_out = 2.0;
			ssr_depth_tolerance = 0.2;
			ssr_roughness = true;

			ssao_enabled = false;
			ssao_intensity = 1.0;
			ssao_radius = 1.0;
			ssao_intensity2 = 1.0;
			ssao_radius2 = 0.0;
			ssao_bias = 0.01;
			ssao_light_affect = 0;
			ssao_filter = VS::ENV_SSAO_BLUR_3x3;
			ssao_quality = VS::ENV_SSAO_QUALITY_LOW;
			ssao_bilateral_sharpness = 4;

			tone_mapper = VS::ENV_TONE_MAPPER_LINEAR;
			tone_mapper_exposure = 1.0;
			tone_mapper_exposure_white = 1.0;
			auto_exposure = false;
			auto_exposure_speed = 0.5;
			auto_exposure_min = 0.05;
			auto_exposure_max = 8;
			auto_exposure_grey = 0.4;

			glow_enabled = false;
			glow_levels = (1 << 2) | (1 << 4);
			glow_intensity = 0.8;
			glow_strength = 1.0;
			glow_bloom = 0.0;
			glow_blend_mode = VS::GLOW_BLEND_MODE_SOFTLIGHT;
			glow_hdr_bleed_threshold = 1.0;
			glow_hdr_bleed_scale = 2.0;
			glow_bicubic_upscale = false;

			dof_blur_far_enabled = false;
			dof_blur_far_distance = 10;
			dof_blur_far_transition = 5;
			dof_blur_far_amount = 0.1;
			dof_blur_far_quality = VS::ENV_DOF_BLUR_QUALITY_MEDIUM;

			dof_blur_near_enabled = false;
			dof_blur_near_distance = 2;
			dof_blur_near_transition = 1;
			dof_blur_near_amount = 0.1;
			dof_blur_near_quality = VS::ENV_DOF_BLUR_QUALITY_MEDIUM;

			adjustments_enabled = false;
			adjustments_brightness = 1.0;
			adjustments_contrast = 1.0;
			adjustments_saturation = 1.0;

			fog_enabled = false;
			fog_color = Color(0.5, 0.5, 0.5);
			fog_sun_color = Color(0.8, 0.8, 0.0);
			fog_sun_amount = 0;

			fog_depth_enabled = true;

			fog_depth_begin = 10;
			fog_depth_curve = 1;

			fog_transmit_enabled = true;
			fog_transmit_curve = 1;

			fog_height_enabled = false;
			fog_height_min = 0;
			fog_height_max = 100;
			fog_height_curve = 1;
		}
	};

	RID_Owner<Environment> environment_owner;

	virtual RID environment_create();

	virtual void environment_set_background(RID p_env, VS::EnvironmentBG p_bg);
	virtual void environment_set_sky(RID p_env, RID p_sky);
	virtual void environment_set_sky_custom_fov(RID p_env, float p_scale);
	virtual void environment_set_bg_color(RID p_env, const Color &p_color);
	virtual void environment_set_bg_energy(RID p_env, float p_energy);
	virtual void environment_set_canvas_max_layer(RID p_env, int p_max_layer);
	virtual void environment_set_ambient_light(RID p_env, const Color &p_color, float p_energy = 1.0, float p_sky_contribution = 0.0);

	virtual void environment_set_dof_blur_near(RID p_env, bool p_enable, float p_distance, float p_transition, float p_amount, VS::EnvironmentDOFBlurQuality p_quality);
	virtual void environment_set_dof_blur_far(RID p_env, bool p_enable, float p_distance, float p_transition, float p_amount, VS::EnvironmentDOFBlurQuality p_quality);
	virtual void environment_set_glow(RID p_env, bool p_enable, int p_level_flags, float p_intensity, float p_strength, float p_bloom_threshold, VS::EnvironmentGlowBlendMode p_blend_mode, float p_hdr_bleed_threshold, float p_hdr_bleed_scale, bool p_bicubic_upscale);
	virtual void environment_set_fog(RID p_env, bool p_enable, float p_begin, float p_end, RID p_gradient_texture);

	virtual void environment_set_ssr(RID p_env, bool p_enable, int p_max_steps, float p_fade_in, float p_fade_out, float p_depth_tolerance, bool p_roughness);
	virtual void environment_set_ssao(RID p_env, bool p_enable, float p_radius, float p_intensity, float p_radius2, float p_intensity2, float p_bias, float p_light_affect, const Color &p_color, VS::EnvironmentSSAOQuality p_quality, VS::EnvironmentSSAOBlur p_blur, float p_bilateral_sharpness);

	virtual void environment_set_tonemap(RID p_env, VS::EnvironmentToneMapper p_tone_mapper, float p_exposure, float p_white, bool p_auto_exposure, float p_min_luminance, float p_max_luminance, float p_auto_exp_speed, float p_auto_exp_scale);

	virtual void environment_set_adjustment(RID p_env, bool p_enable, float p_brightness, float p_contrast, float p_saturation, RID p_ramp);

	virtual void environment_set_fog(RID p_env, bool p_enable, const Color &p_color, const Color &p_sun_color, float p_sun_amount);
	virtual void environment_set_fog_depth(RID p_env, bool p_enable, float p_depth_begin, float p_depth_curve, bool p_transmit, float p_transmit_curve);
	virtual void environment_set_fog_height(RID p_env, bool p_enable, float p_min_height, float p_max_height, float p_height_curve);

	virtual bool is_environment(RID p_env);

	virtual VS::EnvironmentBG environment_get_background(RID p_env);
	virtual int environment_get_canvas_max_layer(RID p_env);

	/* LIGHT INSTANCE */

	struct LightDataUBO {

		float light_pos_inv_radius[4];
		float light_direction_attenuation[4];
		float light_color_energy[4];
		float light_params[4]; //spot attenuation, spot angle, specular, shadow enabled
		float light_clamp[4];
		float light_shadow_color_contact[4];
		float shadow_matrix1[16]; //up to here for spot and omni, rest is for directional
		float shadow_matrix2[16];
		float shadow_matrix3[16];
		float shadow_matrix4[16];
		float shadow_split_offsets[4];
	};

	struct LightInstance : public RID_Data {

		struct ShadowTransform {

			CameraMatrix camera;
			Transform transform;
			float farplane;
			float split;
			float bias_scale;
		};

		ShadowTransform shadow_transform[4];

		RID self;
		RID light;
		RasterizerStorageGLES3::Light *light_ptr;
		Transform transform;

		Vector3 light_vector;
		Vector3 spot_vector;
		float linear_att;

		uint64_t shadow_pass;
		uint64_t last_scene_pass;
		uint64_t last_scene_shadow_pass;
		uint64_t last_pass;
		uint16_t light_index;
		uint16_t light_directional_index;

		uint32_t current_shadow_atlas_key;

		Vector2 dp;

		Rect2 directional_rect;

		Set<RID> shadow_atlases; //shadow atlases where this light is registered

		LightInstance() {}
	};

	mutable RID_Owner<LightInstance> light_instance_owner;

	virtual RID light_instance_create(RID p_light);
	virtual void light_instance_set_transform(RID p_light_instance, const Transform &p_transform);
	virtual void light_instance_set_shadow_transform(RID p_light_instance, const CameraMatrix &p_projection, const Transform &p_transform, float p_far, float p_split, int p_pass, float p_bias_scale = 1.0);
	virtual void light_instance_mark_visible(RID p_light_instance);

	/* REFLECTION INSTANCE */

	struct GIProbeInstance : public RID_Data {
		RID data;
		RasterizerStorageGLES3::GIProbe *probe;
		GLuint tex_cache;
		Vector3 cell_size_cache;
		Vector3 bounds;
		Transform transform_to_data;

		GIProbeInstance() {
			probe = NULL;
			tex_cache = 0;
		}
	};

	mutable RID_Owner<GIProbeInstance> gi_probe_instance_owner;

	virtual RID gi_probe_instance_create();
	virtual void gi_probe_instance_set_light_data(RID p_probe, RID p_base, RID p_data);
	virtual void gi_probe_instance_set_transform_to_data(RID p_probe, const Transform &p_xform);
	virtual void gi_probe_instance_set_bounds(RID p_probe, const Vector3 &p_bounds);

	/* RENDER LIST */

	struct RenderList {

		enum {
			DEFAULT_MAX_ELEMENTS = 65536,
			SORT_FLAG_SKELETON = 1,
			SORT_FLAG_INSTANCING = 2,
			MAX_DIRECTIONAL_LIGHTS = 16,
			MAX_LIGHTS = 4096,
			MAX_REFLECTIONS = 1024,

			SORT_KEY_PRIORITY_SHIFT = 56,
			SORT_KEY_PRIORITY_MASK = 0xFF,
			//depth layer for opaque (56-52)
			SORT_KEY_OPAQUE_DEPTH_LAYER_SHIFT = 52,
			SORT_KEY_OPAQUE_DEPTH_LAYER_MASK = 0xF,
//64 bits unsupported in MSVC
#define SORT_KEY_UNSHADED_FLAG (uint64_t(1) << 49)
#define SORT_KEY_NO_DIRECTIONAL_FLAG (uint64_t(1) << 48)
#define SORT_KEY_LIGHTMAP_CAPTURE_FLAG (uint64_t(1) << 47)
#define SORT_KEY_LIGHTMAP_FLAG (uint64_t(1) << 46)
#define SORT_KEY_GI_PROBES_FLAG (uint64_t(1) << 45)
#define SORT_KEY_VERTEX_LIT_FLAG (uint64_t(1) << 44)
			SORT_KEY_SHADING_SHIFT = 44,
			SORT_KEY_SHADING_MASK = 63,
			//44-28 material index
			SORT_KEY_MATERIAL_INDEX_SHIFT = 28,
			//28-8 geometry index
			SORT_KEY_GEOMETRY_INDEX_SHIFT = 8,
			//bits 5-7 geometry type
			SORT_KEY_GEOMETRY_TYPE_SHIFT = 5,
			//bits 0-5 for flags
			SORT_KEY_OPAQUE_PRE_PASS = 8,
			SORT_KEY_CULL_DISABLED_FLAG = 4,
			SORT_KEY_SKELETON_FLAG = 2,
			SORT_KEY_MIRROR_FLAG = 1

		};

		int max_elements;

		struct Element {

			RasterizerScene::InstanceBase *instance;
			RasterizerStorageGLES3::Geometry *geometry;
			RasterizerStorageGLES3::Material *material;
			RasterizerStorageGLES3::GeometryOwner *owner;
			uint64_t sort_key;
		};

		Element *base_elements;
		Element **elements;

		int element_count;
		int alpha_element_count;

		void clear() {

			element_count = 0;
			alpha_element_count = 0;
		}

		//should eventually be replaced by radix

		struct SortByKey {

			_FORCE_INLINE_ bool operator()(const Element *A, const Element *B) const {
				return A->sort_key < B->sort_key;
			}
		};

		void sort_by_key(bool p_alpha) {

			SortArray<Element *, SortByKey> sorter;
			if (p_alpha) {
				sorter.sort(&elements[max_elements - alpha_element_count], alpha_element_count);
			} else {
				sorter.sort(elements, element_count);
			}
		}

		struct SortByDepth {

			_FORCE_INLINE_ bool operator()(const Element *A, const Element *B) const {
				return A->instance->depth < B->instance->depth;
			}
		};

		void sort_by_depth(bool p_alpha) { //used for shadows

			SortArray<Element *, SortByDepth> sorter;
			if (p_alpha) {
				sorter.sort(&elements[max_elements - alpha_element_count], alpha_element_count);
			} else {
				sorter.sort(elements, element_count);
			}
		}

		struct SortByReverseDepthAndPriority {

			_FORCE_INLINE_ bool operator()(const Element *A, const Element *B) const {
				uint32_t layer_A = uint32_t(A->sort_key >> SORT_KEY_PRIORITY_SHIFT);
				uint32_t layer_B = uint32_t(B->sort_key >> SORT_KEY_PRIORITY_SHIFT);
				if (layer_A == layer_B) {
					return A->instance->depth > B->instance->depth;
				} else {
					return layer_A < layer_B;
				}
			}
		};

		void sort_by_reverse_depth_and_priority(bool p_alpha) { //used for alpha

			SortArray<Element *, SortByReverseDepthAndPriority> sorter;
			if (p_alpha) {
				sorter.sort(&elements[max_elements - alpha_element_count], alpha_element_count);
			} else {
				sorter.sort(elements, element_count);
			}
		}

		_FORCE_INLINE_ Element *add_element() {

			if (element_count + alpha_element_count >= max_elements)
				return NULL;
			elements[element_count] = &base_elements[element_count];
			return elements[element_count++];
		}

		_FORCE_INLINE_ Element *add_alpha_element() {

			if (element_count + alpha_element_count >= max_elements)
				return NULL;
			int idx = max_elements - alpha_element_count - 1;
			elements[idx] = &base_elements[idx];
			alpha_element_count++;
			return elements[idx];
		}

		void init() {

			element_count = 0;
			alpha_element_count = 0;
			elements = memnew_arr(Element *, max_elements);
			base_elements = memnew_arr(Element, max_elements);
			for (int i = 0; i < max_elements; i++)
				elements[i] = &base_elements[i]; // assign elements
		}

		RenderList() {

			max_elements = DEFAULT_MAX_ELEMENTS;
		}

		~RenderList() {
			memdelete_arr(elements);
			memdelete_arr(base_elements);
		}
	};

	LightInstance *directional_light;
	LightInstance *directional_lights[RenderList::MAX_DIRECTIONAL_LIGHTS];

	RenderList render_list;

	_FORCE_INLINE_ void _set_cull(bool p_front, bool p_disabled, bool p_reverse_cull);

	_FORCE_INLINE_ bool _setup_material(RasterizerStorageGLES3::Material *p_material, bool p_alpha_pass);
	_FORCE_INLINE_ void _setup_geometry(RenderList::Element *e, const Transform &p_view_transform);
	_FORCE_INLINE_ void _render_geometry(RenderList::Element *e);
	_FORCE_INLINE_ void _setup_light(RenderList::Element *e, const Transform &p_view_transform);

	void _render_list(RenderList::Element **p_elements, int p_element_count, const Transform &p_view_transform, const CameraMatrix &p_projection, GLuint p_base_env, bool p_reverse_cull, bool p_alpha_pass, bool p_shadow, bool p_directional_add, bool p_directional_shadows);

	_FORCE_INLINE_ void _add_geometry(RasterizerStorageGLES3::Geometry *p_geometry, InstanceBase *p_instance, RasterizerStorageGLES3::GeometryOwner *p_owner, int p_material, bool p_depth_pass, bool p_shadow_pass);

	_FORCE_INLINE_ void _add_geometry_with_material(RasterizerStorageGLES3::Geometry *p_geometry, InstanceBase *p_instance, RasterizerStorageGLES3::GeometryOwner *p_owner, RasterizerStorageGLES3::Material *p_material, bool p_depth_pass, bool p_shadow_pass);

	void _draw_sky(RasterizerStorageGLES3::Sky *p_sky, const CameraMatrix &p_projection, const Transform &p_transform, bool p_vflip, float p_custom_fov, float p_energy);

	void _setup_environment(Environment *env, const CameraMatrix &p_cam_projection, const Transform &p_cam_transform);
	void _setup_directional_light(int p_index, const Transform &p_camera_inverse_transform, bool p_use_shadows);
	void _setup_lights(RID *p_light_cull_result, int p_light_cull_count, const Transform &p_camera_inverse_transform, const CameraMatrix &p_camera_projection, RID p_shadow_atlas);
	void _setup_reflections(RID *p_reflection_probe_cull_result, int p_reflection_probe_cull_count, const Transform &p_camera_inverse_transform, const CameraMatrix &p_camera_projection, RID p_reflection_atlas, Environment *p_env);

	void _copy_screen(bool p_invalidate_color = false, bool p_invalidate_depth = false);
	void _copy_to_front_buffer(Environment *env);
	void _copy_texture_to_front_buffer(GLuint p_texture); //used for debug

	void _fill_render_list(InstanceBase **p_cull_result, int p_cull_count, bool p_depth_pass, bool p_shadow_pass);

	void _blur_effect_buffer();
	void _render_mrts(Environment *env, const CameraMatrix &p_cam_projection);
	void _post_process(Environment *env, const CameraMatrix &p_cam_projection);

	virtual void render_scene(const Transform &p_cam_transform, const CameraMatrix &p_cam_projection, bool p_cam_ortogonal, InstanceBase **p_cull_result, int p_cull_count, RID *p_light_cull_result, int p_light_cull_count, RID *p_reflection_probe_cull_result, int p_reflection_probe_cull_count, RID p_environment, RID p_shadow_atlas, RID p_reflection_atlas, RID p_reflection_probe, int p_reflection_probe_pass);
	virtual void render_shadow(RID p_light, RID p_shadow_atlas, int p_pass, InstanceBase **p_cull_result, int p_cull_count);
	virtual bool free(RID p_rid);

	virtual void set_scene_pass(uint64_t p_pass);
	virtual void set_debug_draw_mode(VS::ViewportDebugDraw p_debug_draw);

	void iteration();
	void initialize();
	void finalize();
	RasterizerSceneGLES3();
	~RasterizerSceneGLES3();
};

#endif // RASTERIZERSCENEGLES3_H
