From bbccaa2cda895be6e614f5933f6d5aa1ab7f2d4a Mon Sep 17 00:00:00 2001
From: luboslenco <lubos.lenco@gmail.com>
Date: Mon, 11 May 2026 20:26:08 +0200
Subject: [PATCH] paint: improve particles

---
 paint/sources/base.c      |  9 ++++++---
 paint/sources/context.c   |  4 ++++
 paint/sources/types.h     |  4 ++++
 paint/sources/ui_header.c | 33 +++++++++++++++++++++++++++++++++
 4 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/paint/sources/base.c b/paint/sources/base.c
index c2624a1d..74c41a5e 100644
--- a/paint/sources/base.c
+++ b/paint/sources/base.c
@@ -1417,8 +1417,11 @@ void ui_base_update(void *_) {
 			iron_delay_idle_sleep();
 		}
 
+		static f64 particle_last_spawn_time = 0.0;
 		bool particle_just_fired = false;
-		if (mouse_started("left") && context_in_paint_area() && !g_context->paint2d) {
+		if (mouse_down("left") && context_in_paint_area() && !g_context->paint2d &&
+		    (mouse_started("left") || sys_time() - particle_last_spawn_time >= 0.2)) {
+			particle_last_spawn_time = sys_time();
 
 			i32 slot = -1;
 			for (i32 i = 0; i < 32; ++i) {
@@ -1444,7 +1447,7 @@ void ui_base_update(void *_) {
 
 				physics_body_t *body = physics_body_create();
 				body->shape          = PHYSICS_SHAPE_SPHERE;
-				body->mass           = 1.0;
+				body->mass           = g_context->particle_mass;
 				physics_body_init(body, mo->base);
 
 				ray_t *ray = raycast_get_ray(mouse_view_x(), mouse_view_y(), camera);
@@ -1452,7 +1455,7 @@ void ui_base_update(void *_) {
 
 				g_context->particles[slot].body   = body;
 				g_context->particles[slot].bullet = mo->base;
-				g_context->particles[slot].timer  = tween_timer(3, NULL, NULL);
+				g_context->particles[slot].timer  = tween_timer(g_context->particle_lifetime, NULL, NULL);
 				particle_just_fired               = true;
 			}
 		}
diff --git a/paint/sources/context.c b/paint/sources/context.c
index 5ac46e75..d99c60e3 100644
--- a/paint/sources/context.c
+++ b/paint/sources/context.c
@@ -100,6 +100,10 @@ context_t *context_create() {
 	c->last_particle_hit_x               = 0.0;
 	c->last_particle_hit_y               = 0.0;
 	c->last_particle_hit_z               = 0.0;
+	c->particle_friction                 = 0.1;
+	c->particle_bounciness               = 0.0;
+	c->particle_lifetime                 = 5.0;
+	c->particle_mass                     = 1.0;
 	c->layer_filter                      = 0;
 	c->gizmo_started                     = false;
 	c->gizmo_offset                      = 0.0;
diff --git a/paint/sources/types.h b/paint/sources/types.h
index 078f3334..a71a6d75 100644
--- a/paint/sources/types.h
+++ b/paint/sources/types.h
@@ -399,6 +399,10 @@ typedef struct context {
 		struct object       *bullet;
 	} particles[32];
 	i32 particle_index;
+	f32 particle_friction;
+	f32 particle_bounciness;
+	f32 particle_lifetime;
+	f32 particle_mass;
 } context_t;
 
 typedef struct node_shader {
diff --git a/paint/sources/ui_header.c b/paint/sources/ui_header.c
index a9b37e3e..519bdbc4 100644
--- a/paint/sources/ui_header.c
+++ b/paint/sources/ui_header.c
@@ -549,6 +549,38 @@ void ui_header_draw_tool_properties() {
 			}
 		}
 
+		if (g_context->tool == TOOL_TYPE_PARTICLE) {
+			ui_handle_t *hlifetime           = ui_handle(__ID__);
+			if (hlifetime->init) {
+				hlifetime->f = g_context->particle_lifetime;
+			}
+			g_context->particle_lifetime = ui_slider(hlifetime, tr("Lifetime"), 0.0, 10.0, true, 1.0, true, UI_ALIGN_RIGHT, true);
+
+			ui_handle_t *hmass               = ui_handle(__ID__);
+			if (hmass->init) {
+				hmass->f = g_context->particle_mass;
+			}
+			g_context->particle_mass = ui_slider(hmass, tr("Mass"), 0.0, 3.0, true, 100.0, true, UI_ALIGN_RIGHT, true);
+
+			ui_handle_t *hfriction           = ui_handle(__ID__);
+			if (hfriction->init) {
+				hfriction->f = g_context->particle_friction;
+			}
+			g_context->particle_friction = ui_slider(hfriction, tr("Friction"), 0.0, 1.0, true, 100.0, true, UI_ALIGN_RIGHT, true);
+			if (hfriction->changed) {
+				asim_set_friction(g_context->particle_friction);
+			}
+
+			ui_handle_t *hbounciness           = ui_handle(__ID__);
+			if (hbounciness->init) {
+				hbounciness->f = g_context->particle_bounciness;
+			}
+			g_context->particle_bounciness = ui_slider(hbounciness, tr("Bounciness"), 0.0, 1.0, true, 100.0, true, UI_ALIGN_RIGHT, true);
+			if (hbounciness->changed) {
+				asim_set_bounciness(g_context->particle_bounciness);
+			}
+		}
+
 		if (g_context->tool == TOOL_TYPE_FILL) {
 			string_array_t *fill_mode_combo = any_array_create_from_raw(
 			    (void *[]){
@@ -643,6 +675,7 @@ void ui_header_draw_tool_properties() {
 			}
 		}
 	}
+
 	if (g_context->tool == TOOL_TYPE_CURSOR) {
 		// if (!sim_running && ui_button("Play")) {
 		// 	sim_play();