1 files changed, 18 insertions, 25 deletions

diff --git a/scene/resources/particle_process_material.cpp b/scene/resources/particle_process_material.cpp
index 0b65b33240..01d26a8bed 100644
--- a/scene/resources/particle_process_material.cpp
+++ b/scene/resources/particle_process_material.cpp
@@ -33,14 +33,12 @@
 #include "core/version.h"
 
 Mutex ParticleProcessMaterial::material_mutex;
-SelfList<ParticleProcessMaterial>::List *ParticleProcessMaterial::dirty_materials = nullptr;
+SelfList<ParticleProcessMaterial>::List ParticleProcessMaterial::dirty_materials;
 HashMap<ParticleProcessMaterial::MaterialKey, ParticleProcessMaterial::ShaderData, ParticleProcessMaterial::MaterialKey> ParticleProcessMaterial::shader_map;
 RBSet<String> ParticleProcessMaterial::min_max_properties;
 ParticleProcessMaterial::ShaderNames *ParticleProcessMaterial::shader_names = nullptr;
 
 void ParticleProcessMaterial::init_shaders() {
-	dirty_materials = memnew(SelfList<ParticleProcessMaterial>::List);
-
 	shader_names = memnew(ShaderNames);
 
 	shader_names->direction = "direction";
@@ -140,15 +138,13 @@ void ParticleProcessMaterial::init_shaders() {
 }
 
 void ParticleProcessMaterial::finish_shaders() {
-	memdelete(dirty_materials);
-	dirty_materials = nullptr;
+	dirty_materials.clear();
 
 	memdelete(shader_names);
+	shader_names = nullptr;
 }
 
 void ParticleProcessMaterial::_update_shader() {
-	dirty_materials->remove(&element);
-
 	MaterialKey mk = _compute_key();
 	if (mk == current_key) {
 		return; //no update required in the end
@@ -634,7 +630,7 @@ void ParticleProcessMaterial::_update_shader() {
 	if (emission_shape == EMISSION_SHAPE_RING) {
 		code += "		\n";
 		code += "		float ring_spawn_angle = rand_from_seed(alt_seed) * 2.0 * pi;\n";
-		code += "		float ring_random_radius = sqrt(rand_from_seed(alt_seed) * (emission_ring_radius - emission_ring_inner_radius * emission_ring_inner_radius) + emission_ring_inner_radius * emission_ring_inner_radius);\n";
+		code += "		float ring_random_radius = sqrt(rand_from_seed(alt_seed) * (emission_ring_radius * emission_ring_radius - emission_ring_inner_radius * emission_ring_inner_radius) + emission_ring_inner_radius * emission_ring_inner_radius);\n";
 		code += "		vec3 axis = emission_ring_axis == vec3(0.0) ? vec3(0.0, 0.0, 1.0) : normalize(emission_ring_axis);\n";
 		code += "		vec3 ortho_axis = vec3(0.0);\n";
 		code += "		if (abs(axis) == vec3(1.0, 0.0, 0.0)) {\n";
@@ -995,13 +991,15 @@ void ParticleProcessMaterial::_update_shader() {
 	code += "	\n";
 	if (collision_mode == COLLISION_RIGID) {
 		code += "	if (COLLIDED) {\n";
-		code += "		if (length(VELOCITY) > 3.0) {\n";
-		code += "			TRANSFORM[3].xyz += COLLISION_NORMAL * COLLISION_DEPTH;\n";
-		code += "			VELOCITY -= COLLISION_NORMAL * dot(COLLISION_NORMAL, VELOCITY) * (1.0 + collision_bounce);\n";
-		code += "			VELOCITY = mix(VELOCITY,vec3(0.0),clamp(collision_friction, 0.0, 1.0));\n";
-		code += "		} else {\n";
-		code += "			VELOCITY = vec3(0.0);\n";
-		code += "		}\n";
+		code += "		float collision_response = dot(COLLISION_NORMAL, VELOCITY);\n";
+		code += "		float slide_to_bounce_trigger = step(2.0/clamp(collision_bounce + 1.0, 1.0, 2.0), abs(collision_response));\n";
+		code += "		TRANSFORM[3].xyz += COLLISION_NORMAL * COLLISION_DEPTH;\n";
+		code += "		// Remove all components of VELOCITY that is not tangent to COLLISION_NORMAL\n";
+		code += "		VELOCITY -= COLLISION_NORMAL * collision_response;\n";
+		code += "		// Apply friction only to VELOCITY across the surface (Effectively decouples friction and bounce behavior).\n";
+		code += "		VELOCITY = mix(VELOCITY,vec3(0.0),clamp(collision_friction, 0.0, 1.0));\n";
+		code += "		// Add bounce velocity to VELOCITY\n";
+		code += "		VELOCITY -= COLLISION_NORMAL * collision_response * (collision_bounce * slide_to_bounce_trigger);\n";
 		code += "	}\n";
 	} else if (collision_mode == COLLISION_HIDE_ON_CONTACT) {
 		code += "	if (COLLIDED) {\n";
@@ -1170,8 +1168,9 @@ void ParticleProcessMaterial::_update_shader() {
 void ParticleProcessMaterial::flush_changes() {
 	MutexLock lock(material_mutex);
 
-	while (dirty_materials->first()) {
-		dirty_materials->first()->self()->_update_shader();
+	while (dirty_materials.first()) {
+		dirty_materials.first()->self()->_update_shader();
+		dirty_materials.first()->remove_from_list();
 	}
 }
 
@@ -1179,16 +1178,10 @@ void ParticleProcessMaterial::_queue_shader_change() {
 	MutexLock lock(material_mutex);
 
 	if (_is_initialized() && !element.in_list()) {
-		dirty_materials->add(&element);
+		dirty_materials.add(&element);
 	}
 }
 
-bool ParticleProcessMaterial::_is_shader_dirty() const {
-	MutexLock lock(material_mutex);
-
-	return element.in_list();
-}
-
 bool ParticleProcessMaterial::has_min_max_property(const String &p_name) {
 	return min_max_properties.has(p_name);
 }
@@ -2330,7 +2323,7 @@ ParticleProcessMaterial::ParticleProcessMaterial() :
 
 	current_key.invalid_key = 1;
 
-	_mark_initialized(callable_mp(this, &ParticleProcessMaterial::_queue_shader_change));
+	_mark_initialized(callable_mp(this, &ParticleProcessMaterial::_queue_shader_change), callable_mp(this, &ParticleProcessMaterial::_update_shader));
 }
 
 ParticleProcessMaterial::~ParticleProcessMaterial() {