Implement Vector4, Vector4i, Projection

Implement built-in classes Vector4, Vector4i and Projection.

* Two versions of Vector4 (float and integer).
* A Projection class, which is a 4x4 matrix specialized in projection types.

These types have been requested for a long time, but given they were very corner case they were not added before.
Because in Godot 4, reimplementing parts of the rendering engine is now possible, access to these types (heavily used by the rendering code) becomes a necessity.

**Q**: Why Projection and not Matrix4?
**A**: Godot does not use Matrix2, Matrix3, Matrix4x3, etc. naming convention because, within the engine, these types always have a *purpose*. As such, Godot names them: Transform2D, Transform3D or Basis. In this case, this 4x4 matrix is _always_ used as a _Projection_, hence the naming.

2 files changed, 20 insertions, 20 deletions

diff --git a/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.cpp b/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.cpp
index d6613a60cc..d92f37e21e 100644
--- a/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.cpp
+++ b/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.cpp
@@ -800,12 +800,12 @@ void RenderForwardClustered::_render_list_with_threads(RenderListParameters *p_p
 }
 
 void RenderForwardClustered::_setup_environment(const RenderDataRD *p_render_data, bool p_no_fog, const Size2i &p_screen_size, bool p_flip_y, const Color &p_default_bg_color, bool p_opaque_render_buffers, bool p_pancake_shadows, int p_index) {
-	//CameraMatrix projection = p_render_data->cam_projection;
+	//Projection projection = p_render_data->cam_projection;
 	//projection.flip_y(); // Vulkan and modern APIs use Y-Down
-	CameraMatrix correction;
+	Projection correction;
 	correction.set_depth_correction(p_flip_y);
 	correction.add_jitter_offset(p_render_data->taa_jitter);
-	CameraMatrix projection = correction * p_render_data->cam_projection;
+	Projection projection = correction * p_render_data->cam_projection;
 
 	//store camera into ubo
 	RendererRD::MaterialStorage::store_camera(projection, scene_state.ubo.projection_matrix);
@@ -995,10 +995,10 @@ void RenderForwardClustered::_setup_environment(const RenderDataRD *p_render_dat
 		if (render_buffers->use_taa || get_debug_draw_mode() == RS::VIEWPORT_DEBUG_DRAW_MOTION_VECTORS) {
 			memcpy(&scene_state.prev_ubo, &scene_state.ubo, sizeof(SceneState::UBO));
 
-			CameraMatrix prev_correction;
+			Projection prev_correction;
 			prev_correction.set_depth_correction(true);
 			prev_correction.add_jitter_offset(p_render_data->prev_taa_jitter);
-			CameraMatrix prev_projection = prev_correction * p_render_data->prev_cam_projection;
+			Projection prev_projection = prev_correction * p_render_data->prev_cam_projection;
 
 			//store camera into ubo
 			RendererRD::MaterialStorage::store_camera(prev_projection, scene_state.prev_ubo.projection_matrix);
@@ -1588,9 +1588,9 @@ void RenderForwardClustered::_render_scene(RenderDataRD *p_render_data, const Co
 		if (draw_sky || draw_sky_fog_only || environment_get_reflection_source(p_render_data->environment) == RS::ENV_REFLECTION_SOURCE_SKY || environment_get_ambient_source(p_render_data->environment) == RS::ENV_AMBIENT_SOURCE_SKY) {
 			RENDER_TIMESTAMP("Setup Sky");
 			RD::get_singleton()->draw_command_begin_label("Setup Sky");
-			CameraMatrix projection = p_render_data->cam_projection;
+			Projection projection = p_render_data->cam_projection;
 			if (p_render_data->reflection_probe.is_valid()) {
-				CameraMatrix correction;
+				Projection correction;
 				correction.set_depth_correction(true);
 				projection = correction * p_render_data->cam_projection;
 			}
@@ -1719,9 +1719,9 @@ void RenderForwardClustered::_render_scene(RenderDataRD *p_render_data, const Co
 		bool will_continue_color = (can_continue_color || draw_sky || draw_sky_fog_only);
 		bool will_continue_depth = (can_continue_depth || draw_sky || draw_sky_fog_only);
 
-		CameraMatrix dc;
+		Projection dc;
 		dc.set_depth_correction(true);
-		CameraMatrix cm = (dc * p_render_data->cam_projection) * CameraMatrix(p_render_data->cam_transform.affine_inverse());
+		Projection cm = (dc * p_render_data->cam_projection) * Projection(p_render_data->cam_transform.affine_inverse());
 		RD::DrawListID draw_list = RD::get_singleton()->draw_list_begin(color_only_framebuffer, RD::INITIAL_ACTION_CONTINUE, will_continue_color ? RD::FINAL_ACTION_CONTINUE : RD::FINAL_ACTION_READ, RD::INITIAL_ACTION_CONTINUE, will_continue_depth ? RD::FINAL_ACTION_CONTINUE : RD::FINAL_ACTION_READ);
 		RD::get_singleton()->draw_command_begin_label("Debug VoxelGIs");
 		for (int i = 0; i < (int)p_render_data->voxel_gi_instances->size(); i++) {
@@ -1736,11 +1736,11 @@ void RenderForwardClustered::_render_scene(RenderDataRD *p_render_data, const Co
 		bool will_continue_color = (can_continue_color || draw_sky || draw_sky_fog_only);
 		bool will_continue_depth = (can_continue_depth || draw_sky || draw_sky_fog_only);
 
-		CameraMatrix dc;
+		Projection dc;
 		dc.set_depth_correction(true);
-		CameraMatrix cms[RendererSceneRender::MAX_RENDER_VIEWS];
+		Projection cms[RendererSceneRender::MAX_RENDER_VIEWS];
 		for (uint32_t v = 0; v < p_render_data->view_count; v++) {
-			cms[v] = (dc * p_render_data->view_projection[v]) * CameraMatrix(p_render_data->cam_transform.affine_inverse());
+			cms[v] = (dc * p_render_data->view_projection[v]) * Projection(p_render_data->cam_transform.affine_inverse());
 		}
 		_debug_sdfgi_probes(p_render_data->render_buffers, color_only_framebuffer, p_render_data->view_count, cms, will_continue_color, will_continue_depth);
 	}
@@ -1751,9 +1751,9 @@ void RenderForwardClustered::_render_scene(RenderDataRD *p_render_data, const Co
 		RD::get_singleton()->draw_command_begin_label("Draw Sky");
 
 		if (p_render_data->reflection_probe.is_valid()) {
-			CameraMatrix correction;
+			Projection correction;
 			correction.set_depth_correction(true);
-			CameraMatrix projection = correction * p_render_data->cam_projection;
+			Projection projection = correction * p_render_data->cam_projection;
 			sky.draw(env, can_continue_color, can_continue_depth, color_only_framebuffer, 1, &projection, p_render_data->cam_transform, time);
 		} else {
 			sky.draw(env, can_continue_color, can_continue_depth, color_only_framebuffer, p_render_data->view_count, p_render_data->view_projection, p_render_data->cam_transform, time);
@@ -1872,7 +1872,7 @@ void RenderForwardClustered::_render_shadow_begin() {
 	scene_state.instance_data[RENDER_LIST_SECONDARY].clear();
 }
 
-void RenderForwardClustered::_render_shadow_append(RID p_framebuffer, const PagedArray<GeometryInstance *> &p_instances, const CameraMatrix &p_projection, const Transform3D &p_transform, float p_zfar, float p_bias, float p_normal_bias, bool p_use_dp, bool p_use_dp_flip, bool p_use_pancake, const Plane &p_camera_plane, float p_lod_distance_multiplier, float p_screen_mesh_lod_threshold, const Rect2i &p_rect, bool p_flip_y, bool p_clear_region, bool p_begin, bool p_end, RendererScene::RenderInfo *p_render_info) {
+void RenderForwardClustered::_render_shadow_append(RID p_framebuffer, const PagedArray<GeometryInstance *> &p_instances, const Projection &p_projection, const Transform3D &p_transform, float p_zfar, float p_bias, float p_normal_bias, bool p_use_dp, bool p_use_dp_flip, bool p_use_pancake, const Plane &p_camera_plane, float p_lod_distance_multiplier, float p_screen_mesh_lod_threshold, const Rect2i &p_rect, bool p_flip_y, bool p_clear_region, bool p_begin, bool p_end, RendererScene::RenderInfo *p_render_info) {
 	uint32_t shadow_pass_index = scene_state.shadow_passes.size();
 
 	SceneState::ShadowPass shadow_pass;
@@ -1962,7 +1962,7 @@ void RenderForwardClustered::_render_shadow_end(uint32_t p_barrier) {
 	RD::get_singleton()->draw_command_end_label();
 }
 
-void RenderForwardClustered::_render_particle_collider_heightfield(RID p_fb, const Transform3D &p_cam_transform, const CameraMatrix &p_cam_projection, const PagedArray<GeometryInstance *> &p_instances) {
+void RenderForwardClustered::_render_particle_collider_heightfield(RID p_fb, const Transform3D &p_cam_transform, const Projection &p_cam_projection, const PagedArray<GeometryInstance *> &p_instances) {
 	RENDER_TIMESTAMP("Setup GPUParticlesCollisionHeightField3D");
 
 	RD::get_singleton()->draw_command_begin_label("Render Collider Heightfield");
@@ -2001,7 +2001,7 @@ void RenderForwardClustered::_render_particle_collider_heightfield(RID p_fb, con
 	RD::get_singleton()->draw_command_end_label();
 }
 
-void RenderForwardClustered::_render_material(const Transform3D &p_cam_transform, const CameraMatrix &p_cam_projection, bool p_cam_orthogonal, const PagedArray<GeometryInstance *> &p_instances, RID p_framebuffer, const Rect2i &p_region) {
+void RenderForwardClustered::_render_material(const Transform3D &p_cam_transform, const Projection &p_cam_projection, bool p_cam_orthogonal, const PagedArray<GeometryInstance *> &p_instances, RID p_framebuffer, const Rect2i &p_region) {
 	RENDER_TIMESTAMP("Setup Rendering 3D Material");
 
 	RD::get_singleton()->draw_command_begin_label("Render 3D Material");
diff --git a/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.h b/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.h
index 6429def4f9..08b8e4234c 100644
--- a/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.h
+++ b/servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.h
@@ -640,14 +640,14 @@ protected:
 	virtual void _render_scene(RenderDataRD *p_render_data, const Color &p_default_bg_color) override;
 
 	virtual void _render_shadow_begin() override;
-	virtual void _render_shadow_append(RID p_framebuffer, const PagedArray<GeometryInstance *> &p_instances, const CameraMatrix &p_projection, const Transform3D &p_transform, float p_zfar, float p_bias, float p_normal_bias, bool p_use_dp, bool p_use_dp_flip, bool p_use_pancake, const Plane &p_camera_plane = Plane(), float p_lod_distance_multiplier = 0.0, float p_screen_mesh_lod_threshold = 0.0, const Rect2i &p_rect = Rect2i(), bool p_flip_y = false, bool p_clear_region = true, bool p_begin = true, bool p_end = true, RendererScene::RenderInfo *p_render_info = nullptr) override;
+	virtual void _render_shadow_append(RID p_framebuffer, const PagedArray<GeometryInstance *> &p_instances, const Projection &p_projection, const Transform3D &p_transform, float p_zfar, float p_bias, float p_normal_bias, bool p_use_dp, bool p_use_dp_flip, bool p_use_pancake, const Plane &p_camera_plane = Plane(), float p_lod_distance_multiplier = 0.0, float p_screen_mesh_lod_threshold = 0.0, const Rect2i &p_rect = Rect2i(), bool p_flip_y = false, bool p_clear_region = true, bool p_begin = true, bool p_end = true, RendererScene::RenderInfo *p_render_info = nullptr) override;
 	virtual void _render_shadow_process() override;
 	virtual void _render_shadow_end(uint32_t p_barrier = RD::BARRIER_MASK_ALL) override;
 
-	virtual void _render_material(const Transform3D &p_cam_transform, const CameraMatrix &p_cam_projection, bool p_cam_orthogonal, const PagedArray<GeometryInstance *> &p_instances, RID p_framebuffer, const Rect2i &p_region) override;
+	virtual void _render_material(const Transform3D &p_cam_transform, const Projection &p_cam_projection, bool p_cam_orthogonal, const PagedArray<GeometryInstance *> &p_instances, RID p_framebuffer, const Rect2i &p_region) override;
 	virtual void _render_uv2(const PagedArray<GeometryInstance *> &p_instances, RID p_framebuffer, const Rect2i &p_region) override;
 	virtual void _render_sdfgi(RID p_render_buffers, const Vector3i &p_from, const Vector3i &p_size, const AABB &p_bounds, const PagedArray<GeometryInstance *> &p_instances, const RID &p_albedo_texture, const RID &p_emission_texture, const RID &p_emission_aniso_texture, const RID &p_geom_facing_texture) override;
-	virtual void _render_particle_collider_heightfield(RID p_fb, const Transform3D &p_cam_transform, const CameraMatrix &p_cam_projection, const PagedArray<GeometryInstance *> &p_instances) override;
+	virtual void _render_particle_collider_heightfield(RID p_fb, const Transform3D &p_cam_transform, const Projection &p_cam_projection, const PagedArray<GeometryInstance *> &p_instances) override;
 
 public:
 	_FORCE_INLINE_ virtual void update_uniform_sets() override {