Implement conversion from `CPUParticles` to `GPUParticles` (3D/2D)

doc/classes/GPUParticles2D.xml

@@ -21,6 +21,13 @@
 				[b]Note:[/b] When using threaded rendering this method synchronizes the rendering thread. Calling it often may have a negative impact on performance.
 			</description>
 		</method>
+		<method name="convert_from_particles">
+			<return type="void" />
+			<param index="0" name="particles" type="Node" />
+			<description>
+				Sets this node's properties to match a given [CPUParticles2D] node.
+			</description>
+		</method>
 		<method name="emit_particle">
 			<return type="void" />
 			<param index="0" name="xform" type="Transform2D" />

doc/classes/GPUParticles3D.xml

@@ -18,6 +18,13 @@
 				Returns the axis-aligned bounding box that contains all the particles that are active in the current frame.
 			</description>
 		</method>
+		<method name="convert_from_particles">
+			<return type="void" />
+			<param index="0" name="particles" type="Node" />
+			<description>
+				Sets this node's properties to match a given [CPUParticles3D] node.
+			</description>
+		</method>
 		<method name="emit_particle">
 			<return type="void" />
 			<param index="0" name="xform" type="Transform3D" />

editor/plugins/cpu_particles_2d_editor_plugin.cpp

@@ -33,8 +33,11 @@
 #include "canvas_item_editor_plugin.h"
 #include "core/io/image_loader.h"
 #include "editor/editor_node.h"
+#include "editor/editor_undo_redo_manager.h"
 #include "editor/gui/editor_file_dialog.h"
+#include "editor/scene_tree_dock.h"
 #include "scene/2d/cpu_particles_2d.h"
+#include "scene/2d/gpu_particles_2d.h"
 #include "scene/gui/check_box.h"
 #include "scene/gui/menu_button.h"
 #include "scene/gui/option_button.h"
@@ -67,14 +70,26 @@ void CPUParticles2DEditorPlugin::_menu_callback(int p_idx) {
 	switch (p_idx) {
 		case MENU_LOAD_EMISSION_MASK: {
 			file->popup_file_dialog();
-
 		} break;
 		case MENU_CLEAR_EMISSION_MASK: {
 			emission_mask->popup_centered();
 		} break;
 		case MENU_RESTART: {
 			particles->restart();
-		}
+		} break;
+		case MENU_CONVERT_TO_GPU_PARTICLES: {
+			GPUParticles2D *gpu_particles = memnew(GPUParticles2D);
+			gpu_particles->convert_from_particles(particles);
+			gpu_particles->set_name(particles->get_name());
+			gpu_particles->set_transform(particles->get_transform());
+			gpu_particles->set_visible(particles->is_visible());
+			gpu_particles->set_process_mode(particles->get_process_mode());
+
+			EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
+			ur->create_action(TTR("Convert to GPUParticles3D"));
+			SceneTreeDock::get_singleton()->replace_node(particles, gpu_particles);
+			ur->commit_action(false);
+		} break;
 	}
 }
 
@@ -257,6 +272,7 @@ CPUParticles2DEditorPlugin::CPUParticles2DEditorPlugin() {
 	menu = memnew(MenuButton);
 	menu->get_popup()->add_item(TTR("Restart"), MENU_RESTART);
 	menu->get_popup()->add_item(TTR("Load Emission Mask"), MENU_LOAD_EMISSION_MASK);
+	menu->get_popup()->add_item(TTR("Convert to GPUParticles2D"), MENU_CONVERT_TO_GPU_PARTICLES);
 	menu->set_text(TTR("CPUParticles2D"));
 	menu->set_switch_on_hover(true);
 	toolbar->add_child(menu);

editor/plugins/cpu_particles_2d_editor_plugin.h

@@ -49,7 +49,8 @@ class CPUParticles2DEditorPlugin : public EditorPlugin {
 	enum {
 		MENU_LOAD_EMISSION_MASK,
 		MENU_CLEAR_EMISSION_MASK,
-		MENU_RESTART
+		MENU_RESTART,
+		MENU_CONVERT_TO_GPU_PARTICLES,
 	};
 
 	enum EmissionMode {

editor/plugins/cpu_particles_3d_editor_plugin.cpp

@@ -31,8 +31,10 @@
 #include "cpu_particles_3d_editor_plugin.h"
 
 #include "editor/editor_node.h"
+#include "editor/editor_undo_redo_manager.h"
 #include "editor/gui/scene_tree_editor.h"
 #include "editor/plugins/node_3d_editor_plugin.h"
+#include "editor/scene_tree_dock.h"
 #include "scene/gui/menu_button.h"
 
 void CPUParticles3DEditor::_node_removed(Node *p_node) {
@@ -59,6 +61,20 @@ void CPUParticles3DEditor::_menu_option(int p_option) {
 
 		case MENU_OPTION_RESTART: {
 			node->restart();
+		} break;
+
+		case MENU_OPTION_CONVERT_TO_GPU_PARTICLES: {
+			GPUParticles3D *gpu_particles = memnew(GPUParticles3D);
+			gpu_particles->convert_from_particles(node);
+			gpu_particles->set_name(node->get_name());
+			gpu_particles->set_transform(node->get_transform());
+			gpu_particles->set_visible(node->is_visible());
+			gpu_particles->set_process_mode(node->get_process_mode());
+
+			EditorUndoRedoManager *ur = EditorUndoRedoManager::get_singleton();
+			ur->create_action(TTR("Convert to GPUParticles3D"));
+			SceneTreeDock::get_singleton()->replace_node(node, gpu_particles);
+			ur->commit_action(false);
 
 		} break;
 	}
@@ -102,6 +118,7 @@ CPUParticles3DEditor::CPUParticles3DEditor() {
 	options->set_text(TTR("CPUParticles3D"));
 	options->get_popup()->add_item(TTR("Restart"), MENU_OPTION_RESTART);
 	options->get_popup()->add_item(TTR("Create Emission Points From Node"), MENU_OPTION_CREATE_EMISSION_VOLUME_FROM_NODE);
+	options->get_popup()->add_item(TTR("Convert to GPUParticles3D"), MENU_OPTION_CONVERT_TO_GPU_PARTICLES);
 	options->get_popup()->connect("id_pressed", callable_mp(this, &CPUParticles3DEditor::_menu_option));
 }
 

editor/plugins/cpu_particles_3d_editor_plugin.h

@@ -40,8 +40,8 @@ class CPUParticles3DEditor : public GPUParticles3DEditorBase {
 	enum Menu {
 		MENU_OPTION_CREATE_EMISSION_VOLUME_FROM_NODE,
 		MENU_OPTION_CLEAR_EMISSION_VOLUME,
-		MENU_OPTION_RESTART
+		MENU_OPTION_RESTART,
-
+		MENU_OPTION_CONVERT_TO_GPU_PARTICLES,
 	};
 
 	CPUParticles3D *node = nullptr;

scene/2d/gpu_particles_2d.cpp

@@ -30,7 +30,10 @@
 
 #include "gpu_particles_2d.h"
 
+#include "scene/2d/cpu_particles_2d.h"
 #include "scene/resources/atlas_texture.h"
+#include "scene/resources/curve_texture.h"
+#include "scene/resources/gradient_texture.h"
 #include "scene/resources/particle_process_material.h"
 #include "scene/scene_string_names.h"
 
@@ -435,6 +438,97 @@ void GPUParticles2D::restart() {
 	}
 }
 
+void GPUParticles2D::convert_from_particles(Node *p_particles) {
+	CPUParticles2D *cpu_particles = Object::cast_to<CPUParticles2D>(p_particles);
+	ERR_FAIL_NULL_MSG(cpu_particles, "Only CPUParticles2D nodes can be converted to GPUParticles2D.");
+
+	set_emitting(cpu_particles->is_emitting());
+	set_amount(cpu_particles->get_amount());
+	set_lifetime(cpu_particles->get_lifetime());
+	set_one_shot(cpu_particles->get_one_shot());
+	set_pre_process_time(cpu_particles->get_pre_process_time());
+	set_explosiveness_ratio(cpu_particles->get_explosiveness_ratio());
+	set_randomness_ratio(cpu_particles->get_randomness_ratio());
+	set_use_local_coordinates(cpu_particles->get_use_local_coordinates());
+	set_fixed_fps(cpu_particles->get_fixed_fps());
+	set_fractional_delta(cpu_particles->get_fractional_delta());
+	set_speed_scale(cpu_particles->get_speed_scale());
+	set_draw_order(DrawOrder(cpu_particles->get_draw_order()));
+	set_texture(cpu_particles->get_texture());
+
+	Ref<Material> mat = cpu_particles->get_material();
+	if (mat.is_valid()) {
+		set_material(mat);
+	}
+
+	Ref<ParticleProcessMaterial> proc_mat = memnew(ParticleProcessMaterial);
+	set_process_material(proc_mat);
+	Vector2 dir = cpu_particles->get_direction();
+	proc_mat->set_direction(Vector3(dir.x, dir.y, 0));
+	proc_mat->set_spread(cpu_particles->get_spread());
+	proc_mat->set_color(cpu_particles->get_color());
+
+	Ref<Gradient> color_grad = cpu_particles->get_color_ramp();
+	if (color_grad.is_valid()) {
+		Ref<GradientTexture1D> tex = memnew(GradientTexture1D);
+		tex->set_gradient(color_grad);
+		proc_mat->set_color_ramp(tex);
+	}
+
+	Ref<Gradient> color_init_grad = cpu_particles->get_color_initial_ramp();
+	if (color_init_grad.is_valid()) {
+		Ref<GradientTexture1D> tex = memnew(GradientTexture1D);
+		tex->set_gradient(color_init_grad);
+		proc_mat->set_color_initial_ramp(tex);
+	}
+
+	proc_mat->set_particle_flag(ParticleProcessMaterial::PARTICLE_FLAG_ALIGN_Y_TO_VELOCITY, cpu_particles->get_particle_flag(CPUParticles2D::PARTICLE_FLAG_ALIGN_Y_TO_VELOCITY));
+
+	proc_mat->set_emission_shape(ParticleProcessMaterial::EmissionShape(cpu_particles->get_emission_shape()));
+	proc_mat->set_emission_sphere_radius(cpu_particles->get_emission_sphere_radius());
+
+	Vector2 rect_extents = cpu_particles->get_emission_rect_extents();
+	proc_mat->set_emission_box_extents(Vector3(rect_extents.x, rect_extents.y, 0));
+
+	if (cpu_particles->get_split_scale()) {
+		Ref<CurveXYZTexture> scale3D = memnew(CurveXYZTexture);
+		scale3D->set_curve_x(cpu_particles->get_scale_curve_x());
+		scale3D->set_curve_y(cpu_particles->get_scale_curve_y());
+		proc_mat->set_param_texture(ParticleProcessMaterial::PARAM_SCALE, scale3D);
+	}
+
+	Vector2 gravity = cpu_particles->get_gravity();
+	proc_mat->set_gravity(Vector3(gravity.x, gravity.y, 0));
+	proc_mat->set_lifetime_randomness(cpu_particles->get_lifetime_randomness());
+
+#define CONVERT_PARAM(m_param)                                                                                        \
+	proc_mat->set_param_min(ParticleProcessMaterial::m_param, cpu_particles->get_param_min(CPUParticles2D::m_param)); \
+	{                                                                                                                 \
+		Ref<Curve> curve = cpu_particles->get_param_curve(CPUParticles2D::m_param);                                   \
+		if (curve.is_valid()) {                                                                                       \
+			Ref<CurveTexture> tex = memnew(CurveTexture);                                                             \
+			tex->set_curve(curve);                                                                                    \
+			proc_mat->set_param_texture(ParticleProcessMaterial::m_param, tex);                                       \
+		}                                                                                                             \
+	}                                                                                                                 \
+	proc_mat->set_param_max(ParticleProcessMaterial::m_param, cpu_particles->get_param_max(CPUParticles2D::m_param));
+
+	CONVERT_PARAM(PARAM_INITIAL_LINEAR_VELOCITY);
+	CONVERT_PARAM(PARAM_ANGULAR_VELOCITY);
+	CONVERT_PARAM(PARAM_ORBIT_VELOCITY);
+	CONVERT_PARAM(PARAM_LINEAR_ACCEL);
+	CONVERT_PARAM(PARAM_RADIAL_ACCEL);
+	CONVERT_PARAM(PARAM_TANGENTIAL_ACCEL);
+	CONVERT_PARAM(PARAM_DAMPING);
+	CONVERT_PARAM(PARAM_ANGLE);
+	CONVERT_PARAM(PARAM_SCALE);
+	CONVERT_PARAM(PARAM_HUE_VARIATION);
+	CONVERT_PARAM(PARAM_ANIM_SPEED);
+	CONVERT_PARAM(PARAM_ANIM_OFFSET);
+
+#undef CONVERT_PARAM
+}
+
 void GPUParticles2D::_notification(int p_what) {
 	switch (p_what) {
 		case NOTIFICATION_DRAW: {
@@ -680,6 +774,8 @@ void GPUParticles2D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_trail_section_subdivisions", "subdivisions"), &GPUParticles2D::set_trail_section_subdivisions);
 	ClassDB::bind_method(D_METHOD("get_trail_section_subdivisions"), &GPUParticles2D::get_trail_section_subdivisions);
 
+	ClassDB::bind_method(D_METHOD("convert_from_particles", "particles"), &GPUParticles2D::convert_from_particles);
+
 	ADD_SIGNAL(MethodInfo("finished"));
 
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "emitting"), "set_emitting", "is_emitting");

scene/2d/gpu_particles_2d.h

@@ -169,6 +169,8 @@ public:
 
 	void restart();
 	Rect2 capture_rect() const;
+	void convert_from_particles(Node *p_particles);
+
 	GPUParticles2D();
 	~GPUParticles2D();
 };

scene/3d/gpu_particles_3d.cpp

@@ -30,6 +30,9 @@
 
 #include "gpu_particles_3d.h"
 
+#include "scene/3d/cpu_particles_3d.h"
+#include "scene/resources/curve_texture.h"
+#include "scene/resources/gradient_texture.h"
 #include "scene/resources/particle_process_material.h"
 #include "scene/scene_string_names.h"
 
@@ -546,10 +549,98 @@ void GPUParticles3D::set_transform_align(TransformAlign p_align) {
 	transform_align = p_align;
 	RS::get_singleton()->particles_set_transform_align(particles, RS::ParticlesTransformAlign(transform_align));
 }
+
 GPUParticles3D::TransformAlign GPUParticles3D::get_transform_align() const {
 	return transform_align;
 }
 
+void GPUParticles3D::convert_from_particles(Node *p_particles) {
+	CPUParticles3D *cpu_particles = Object::cast_to<CPUParticles3D>(p_particles);
+	ERR_FAIL_NULL_MSG(cpu_particles, "Only CPUParticles3D nodes can be converted to GPUParticles3D.");
+
+	set_emitting(cpu_particles->is_emitting());
+	set_amount(cpu_particles->get_amount());
+	set_lifetime(cpu_particles->get_lifetime());
+	set_one_shot(cpu_particles->get_one_shot());
+	set_pre_process_time(cpu_particles->get_pre_process_time());
+	set_explosiveness_ratio(cpu_particles->get_explosiveness_ratio());
+	set_randomness_ratio(cpu_particles->get_randomness_ratio());
+	set_use_local_coordinates(cpu_particles->get_use_local_coordinates());
+	set_fixed_fps(cpu_particles->get_fixed_fps());
+	set_fractional_delta(cpu_particles->get_fractional_delta());
+	set_speed_scale(cpu_particles->get_speed_scale());
+	set_draw_order(DrawOrder(cpu_particles->get_draw_order()));
+	set_draw_pass_mesh(0, cpu_particles->get_mesh());
+
+	Ref<ParticleProcessMaterial> proc_mat = memnew(ParticleProcessMaterial);
+	set_process_material(proc_mat);
+
+	proc_mat->set_direction(cpu_particles->get_direction());
+	proc_mat->set_spread(cpu_particles->get_spread());
+	proc_mat->set_flatness(cpu_particles->get_flatness());
+	proc_mat->set_color(cpu_particles->get_color());
+
+	Ref<Gradient> grad = cpu_particles->get_color_ramp();
+	if (grad.is_valid()) {
+		Ref<GradientTexture1D> tex = memnew(GradientTexture1D);
+		tex->set_gradient(grad);
+		proc_mat->set_color_ramp(tex);
+	}
+
+	Ref<Gradient> grad_init = cpu_particles->get_color_initial_ramp();
+	if (grad_init.is_valid()) {
+		Ref<GradientTexture1D> tex = memnew(GradientTexture1D);
+		tex->set_gradient(grad_init);
+		proc_mat->set_color_initial_ramp(tex);
+	}
+
+	proc_mat->set_particle_flag(ParticleProcessMaterial::PARTICLE_FLAG_ALIGN_Y_TO_VELOCITY, cpu_particles->get_particle_flag(CPUParticles3D::PARTICLE_FLAG_ALIGN_Y_TO_VELOCITY));
+	proc_mat->set_particle_flag(ParticleProcessMaterial::PARTICLE_FLAG_ROTATE_Y, cpu_particles->get_particle_flag(CPUParticles3D::PARTICLE_FLAG_ROTATE_Y));
+	proc_mat->set_particle_flag(ParticleProcessMaterial::PARTICLE_FLAG_DISABLE_Z, cpu_particles->get_particle_flag(CPUParticles3D::PARTICLE_FLAG_DISABLE_Z));
+
+	proc_mat->set_emission_shape(ParticleProcessMaterial::EmissionShape(cpu_particles->get_emission_shape()));
+	proc_mat->set_emission_sphere_radius(cpu_particles->get_emission_sphere_radius());
+	proc_mat->set_emission_box_extents(cpu_particles->get_emission_box_extents());
+
+	if (cpu_particles->get_split_scale()) {
+		Ref<CurveXYZTexture> scale3D = memnew(CurveXYZTexture);
+		scale3D->set_curve_x(cpu_particles->get_scale_curve_x());
+		scale3D->set_curve_y(cpu_particles->get_scale_curve_y());
+		scale3D->set_curve_z(cpu_particles->get_scale_curve_z());
+		proc_mat->set_param_texture(ParticleProcessMaterial::PARAM_SCALE, scale3D);
+	}
+
+	proc_mat->set_gravity(cpu_particles->get_gravity());
+	proc_mat->set_lifetime_randomness(cpu_particles->get_lifetime_randomness());
+
+#define CONVERT_PARAM(m_param)                                                                                        \
+	proc_mat->set_param_min(ParticleProcessMaterial::m_param, cpu_particles->get_param_min(CPUParticles3D::m_param)); \
+	{                                                                                                                 \
+		Ref<Curve> curve = cpu_particles->get_param_curve(CPUParticles3D::m_param);                                   \
+		if (curve.is_valid()) {                                                                                       \
+			Ref<CurveTexture> tex = memnew(CurveTexture);                                                             \
+			tex->set_curve(curve);                                                                                    \
+			proc_mat->set_param_texture(ParticleProcessMaterial::m_param, tex);                                       \
+		}                                                                                                             \
+	}                                                                                                                 \
+	proc_mat->set_param_max(ParticleProcessMaterial::m_param, cpu_particles->get_param_max(CPUParticles3D::m_param));
+
+	CONVERT_PARAM(PARAM_INITIAL_LINEAR_VELOCITY);
+	CONVERT_PARAM(PARAM_ANGULAR_VELOCITY);
+	CONVERT_PARAM(PARAM_ORBIT_VELOCITY);
+	CONVERT_PARAM(PARAM_LINEAR_ACCEL);
+	CONVERT_PARAM(PARAM_RADIAL_ACCEL);
+	CONVERT_PARAM(PARAM_TANGENTIAL_ACCEL);
+	CONVERT_PARAM(PARAM_DAMPING);
+	CONVERT_PARAM(PARAM_ANGLE);
+	CONVERT_PARAM(PARAM_SCALE);
+	CONVERT_PARAM(PARAM_HUE_VARIATION);
+	CONVERT_PARAM(PARAM_ANIM_SPEED);
+	CONVERT_PARAM(PARAM_ANIM_OFFSET);
+
+#undef CONVERT_PARAM
+}
+
 void GPUParticles3D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_emitting", "emitting"), &GPUParticles3D::set_emitting);
 	ClassDB::bind_method(D_METHOD("set_amount", "amount"), &GPUParticles3D::set_amount);
@@ -613,6 +704,8 @@ void GPUParticles3D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_transform_align", "align"), &GPUParticles3D::set_transform_align);
 	ClassDB::bind_method(D_METHOD("get_transform_align"), &GPUParticles3D::get_transform_align);
 
+	ClassDB::bind_method(D_METHOD("convert_from_particles", "particles"), &GPUParticles3D::convert_from_particles);
+
 	ADD_SIGNAL(MethodInfo("finished"));
 
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "emitting"), "set_emitting", "is_emitting");

scene/3d/gpu_particles_3d.h

@@ -178,6 +178,8 @@ public:
 	void emit_particle(const Transform3D &p_transform, const Vector3 &p_velocity, const Color &p_color, const Color &p_custom, uint32_t p_emit_flags);
 
 	AABB capture_aabb() const;
+	void convert_from_particles(Node *p_particles);
+
 	GPUParticles3D();
 	~GPUParticles3D();
 };