javascript based particle system

scripts/engine.js

@@ -512,6 +512,7 @@ global.mixin("scripts/color");
 global.mixin("scripts/gui");
 global.mixin("scripts/tween");
 global.mixin("scripts/ai");
+global.mixin("scripts/particle");
 
 var timer = {
   update(dt) {

scripts/entity.js

@@ -37,7 +37,6 @@ var entity = {
     this.body = os.make_body(this.transform);
   },
   
-  
   path_from(o) {
     var p = this.toString();
     var c = this.master;

scripts/particle.js

@@ -0,0 +1,105 @@
+var emitter = {};
+emitter.particles = {};
+emitter.life = 10;
+emitter.scale = 1;
+emitter.grow_for = 0;
+emitter.spawn_timer = 0;
+emitter.pps = 0;
+emitter.color = Color.white;
+
+emitter.draw = function()
+{
+  var amt = Object.values(this.particles).length;
+  if (amt === 0) return;
+  render.use_shader(this.shader);
+  render.use_mat(this);
+  var ts = [];
+  for (var p of Object.values(this.particles)) ts.push([p.transform,p.color]);
+  render.make_particle_ssbo(ts, this.ssbo);
+  render.draw(this.shape, this.ssbo, amt);
+}
+
+var std_spawn = function(par)
+{
+}
+
+var std_step = function(p)
+{
+  if (p.time < this.grow_for) {
+    var s = Math.lerp(0, this.scale, p.time/this.grow_for);
+    p.transform.scale = [s,s,s];
+  }
+  else if (p.time > (p.life - this.shrink_for)) {
+    var s = Math.lerp(0,this.scale,(p.life-p.time)/this.shrink_for);
+    p.transform.scale=[s,s,s];
+  } else
+    p.transform.scale = [this.scale,this.scale,this.scale];
+}
+
+var std_die = function(par)
+{
+}
+
+emitter.spawn_hook = std_spawn;
+emitter.step_hook = std_step;
+emitter.die_hook = std_die;
+
+emitter.spawn = function(t)
+{
+  t ??= this.transform;
+  var par = {
+    transform: os.make_transform(),
+    life: this.life,
+    time: 0,
+    color: this.color
+  };
+
+  par.body = os.make_body(par.transform);
+
+  par.body.pos = t.pos;
+  par.transform.scale = [this.scale,this.scale,this.scale];
+  par.id = prosperon.guid();
+  this.particles[par.id] = par;
+
+  this.spawn_hook(par);
+}
+
+emitter.step = function(dt)
+{
+  // update spawning particles
+  if (this.on && this.pps > 0) {
+    this.spawn_timer += dt;
+    var pp = 1/this.pps;
+    while (this.spawn_timer > pp) {
+      this.spawn_timer -= pp;
+      this.spawn();
+    }
+  }
+
+  // update all particles
+  for (var p of Object.values(this.particles)) {
+    p.time += dt;
+
+    this.step_hook(p);
+    
+    if (p.time >= p.life) {
+      this.die_hook(p);
+      delete this.particles[p.id];
+    }
+  }
+}
+
+emitter.burst = function(count, t) {
+  for (var i = 0; i < count; i++) this.spawn(t);
+}
+
+var make_emitter = function()
+{
+  var e = Object.create(emitter);
+  e.ssbo = render.make_textssbo();
+  e.shape = shape.quad;
+  e.shader = render.make_shader("shaders/baseparticle.cg");  
+  return e;
+}
+
+return {make_emitter};

scripts/render.js

@@ -163,8 +163,12 @@ render.set_camera = function(cam)
   setcam(cam);
 }
 
+var shader_cache = {};
+ 
 render.make_shader = function(shader)
 {
+  if (shader_cache[shader]) return shader_cache[shader];
+  
   var file = shader;
   shader = io.slurp(shader);
   if (!shader) {
@@ -188,6 +192,7 @@ render.make_shader = function(shader)
     var shaderobj = json.decode(io.slurp(writejson));
     var obj = shaderobj[os.sys()];
     obj.pipe = render.pipeline(obj);
+    shader_cache[shader] = obj;
     return obj;
   }
   
@@ -304,6 +309,7 @@ render.make_shader = function(shader)
   var obj = compiled[os.sys()];
   obj.pipe = render.pipeline(obj);
 
+  shader_cache[shader] = obj;
   return obj;
 }
 
@@ -640,11 +646,14 @@ render.slice9 = function(tex, pos, bb, scale = [tex.width,tex.height], color = C
 
 render.emitter = function(emit)
 {
-  var amt = emit.draw();
+  var amt = Object.values(emit.particles).length;
   if (amt === 0) return;
   render.use_shader(parshader);
   render.use_mat(emit);
-  render.draw(shape.quad, emit.buffer, amt);
+  var ts = [];
+  for (var p of Object.values(emit.particles)) ts.push([p.transform,p.color]);
+  render.make_particle_ssbo(ts, emit.ssbo);
+  render.draw(shape.quad, emit.ssbo, amt);
 }
 
 var textssbo;

shaders/baseparticle.cg

@@ -8,9 +8,7 @@ in vec2 a_uv;
 uniform vec2 diffuse_size;
 
 struct particle {
-  vec2 pos;
+  mat4 model;
-  float angle;
-  float scale;
   vec4 color;
 };
 
@@ -28,21 +26,16 @@ void main()
 {
   particle p = par[gl_InstanceIndex];
   pos = a_pos - 0.5;
-  vec2 rot = pos;
+  gl_Position = vp * p.model * vec4(pos, 0.0, 1.0);
-  rot.x = pos.x*cos(p.angle) - pos.y*sin(p.angle);
-  rot.y = pos.x*sin(p.angle) + pos.y*cos(p.angle);
-  pos = rot*p.scale;
-  pos += p.pos;
-  color0 = p.color;
-  gl_Position = vp * vec4(pos, 0.0, 1.0);
   uv = a_pos;
+  color0 = p.color;
 }
 @end
 
 @fs fs
 in vec2 uv;
-in vec4 color0;
 
+in vec4 color0;
 out vec4 color;
 
 texture2D diffuse;
@@ -50,7 +43,7 @@ sampler smp;
 
 void main()
 {
-  color = texture(sampler2D(diffuse,smp), uv);
+  color = texture(sampler2D(diffuse,smp),uv);
   color *= color0;
 }
 @end

shaders/sprite.cg

@@ -13,7 +13,6 @@ uniform vec4 shade;
 void frag()
 {
   color = texture(sampler2D(diffuse,smp), uv);
-  if (color.a < 0.1) discard;
   color *= shade;
 }
 @end

source/engine/jsffi.c

@@ -15,7 +15,6 @@
 #include "window.h"
 #include "spline.h"
 #include "yugine.h"
-#include "particle.h"
 #include <assert.h>
 #include "resources.h"
 #include <sokol/sokol_time.h>
@@ -96,7 +95,6 @@ void cpConstraint_free(cpConstraint *c)
 void jsfreestr(const char *s) { JS_FreeCString(js, s); }
 QJSCLASS(gameobject)
 QJSCLASS(transform)
-QJSCLASS(emitter)
 QJSCLASS(dsp_node)
 QJSCLASS(texture)
 QJSCLASS(font)
@@ -661,34 +659,6 @@ sg_bindings js2bind(JSValue v)
   return bind;
 }
 
-JSC_GETSET(emitter, life, number)
-JSC_GETSET(emitter, life_var, number)
-JSC_GETSET(emitter, speed, number)
-JSC_GETSET(emitter, variation, number)
-JSC_GETSET(emitter, divergence, number)
-JSC_GETSET(emitter, scale, number)
-JSC_GETSET(emitter, scale_var, number)
-JSC_GETSET(emitter, grow_for, number)
-JSC_GETSET(emitter, shrink_for, number)
-JSC_GETSET(emitter, color, vec4)
-JSC_GETSET(emitter, max, number)
-JSC_GETSET(emitter, explosiveness, number)
-JSC_GETSET(emitter, bounce, number)
-JSC_GETSET(emitter, collision_mask, bitmask)
-JSC_GETSET(emitter, die_after_collision, boolean)
-JSC_GETSET(emitter, tumble, number)
-JSC_GETSET(emitter, tumble_rate, number)
-JSC_GETSET(emitter, persist, number)
-JSC_GETSET(emitter, persist_var, number)
-JSC_GETSET(emitter, warp_mask, bitmask)
-JSC_CCALL(emitter_emit, emitter_emit(js2emitter(self), js2number(argv[0]), js2transform(argv[1])))
-JSC_CCALL(emitter_step, emitter_step(js2emitter(self), js2number(argv[0]), js2transform(argv[1])))
-JSC_CCALL(emitter_draw,
-  sg_buffer *b = js2sg_buffer(js_getpropstr(self, "buffer"));
-  emitter_draw(js2emitter(self), b);
-  return number2js(arrlen(js2emitter(self)->verts));
-)
-
 JSC_CCALL(render_flushtext,
   sg_buffer *buf = js2sg_buffer(argv[0]);
   int amt = text_flush(buf);
@@ -968,24 +938,67 @@ JSC_CCALL(render_setbind,
   sg_apply_bindings(&bind);
 )
 
+typedef struct particle_ss {
+  HMM_Mat4 model;
+  HMM_Vec4 color;
+} particle_ss;
+
+JSC_CCALL(render_make_particle_ssbo,
+  JSValue array = argv[0];
+  size_t size = js_arrlen(array)*(sizeof(particle_ss));
+  sg_buffer *b = js2sg_buffer(argv[1]);
+  if (!b) return JS_UNDEFINED;
+  
+  particle_ss ms[js_arrlen(array)];
+
+  if (sg_query_buffer_will_overflow(*b, size)) {
+    sg_destroy_buffer(*b);
+    *b = sg_make_buffer(&(sg_buffer_desc){
+      .type = SG_BUFFERTYPE_STORAGEBUFFER,
+      .size = size,
+      .usage = SG_USAGE_STREAM,
+      .label = "transform buffer"
+    });
+  }
+
+  for (int i = 0; i < js_arrlen(array); i++) {
+    JSValue sub = js_getpropidx(array,i);
+    ms[i].model = transform2mat(*js2transform(js_getpropidx(sub, 0)));
+    ms[i].color = js2vec4(js_getpropidx(sub,1));
+  }
+
+  sg_append_buffer(*b, (&(sg_range){
+    .ptr = ms,
+    .size = size
+  }));
+
+)
+
 JSC_CCALL(render_make_t_ssbo,
   JSValue array = argv[0];
+  size_t size = js_arrlen(array)*sizeof(HMM_Mat4);
+  sg_buffer *b = js2sg_buffer(argv[1]);
+  if (!b) return JS_UNDEFINED;
+  
   HMM_Mat4 ms[js_arrlen(array)];
+
+  if (sg_query_buffer_will_overflow(*b, size)) {
+    sg_destroy_buffer(*b);
+    *b = sg_make_buffer(&(sg_buffer_desc){
+      .type = SG_BUFFERTYPE_STORAGEBUFFER,
+      .size = size,
+      .usage = SG_USAGE_STREAM,
+      .label = "transform buffer"
+    });
+  }
+
   for (int i = 0; i < js_arrlen(array); i++)
     ms[i] = transform2mat(*js2transform(js_getpropidx(array, i)));
 
-  sg_buffer *rr = malloc(sizeof(sg_buffer));
+  sg_append_buffer(*b, (&(sg_range){
-  *rr = sg_make_buffer(&(sg_buffer_desc){
-    .data = {
     .ptr = ms,
-      .size = sizeof(HMM_Mat4)*js_arrlen(array),
+    .size = size
-    },
+  }));
-    .type = SG_BUFFERTYPE_STORAGEBUFFER,
-    .usage = SG_USAGE_IMMUTABLE,
-    .label = "transform buffer"
-  });
-
-  return sg_buffer2js(rr);
 )
 
 JSC_CCALL(render_spdraw,
@@ -1037,7 +1050,8 @@ static const JSCFunctionListEntry js_render_funcs[] = {
   MIST_FUNC_DEF(render, gfx_gui, 0),
   MIST_FUNC_DEF(render, imgui_end, 0),
   MIST_FUNC_DEF(render, imgui_init, 0),
-  MIST_FUNC_DEF(render, make_t_ssbo, 1)
+  MIST_FUNC_DEF(render, make_t_ssbo, 2),
+  MIST_FUNC_DEF(render, make_particle_ssbo, 2)
 };
 
 JSC_CCALL(gui_scissor, sg_apply_scissor_rect(js2number(argv[0]), js2number(argv[1]), js2number(argv[2]), js2number(argv[3]), 0))
@@ -1484,32 +1498,6 @@ static const JSCFunctionListEntry js_physics_funcs[] = {
   CGETSET_ADD(physics, collision_persistence),
 };
 
-static const JSCFunctionListEntry js_emitter_funcs[] = {
-  CGETSET_ADD(emitter, life),
-  CGETSET_ADD(emitter, life_var),
-  CGETSET_ADD(emitter, speed),
-  CGETSET_ADD(emitter, variation),
-  CGETSET_ADD(emitter, divergence),
-  CGETSET_ADD(emitter, scale),
-  CGETSET_ADD(emitter, scale_var),
-  CGETSET_ADD(emitter, grow_for),
-  CGETSET_ADD(emitter, shrink_for),
-  CGETSET_ADD(emitter, max),
-  CGETSET_ADD(emitter, color),
-  CGETSET_ADD(emitter, tumble),
-  CGETSET_ADD(emitter, tumble_rate),
-  CGETSET_ADD(emitter, explosiveness),
-  CGETSET_ADD(emitter, bounce),
-  CGETSET_ADD(emitter, collision_mask),
-  CGETSET_ADD(emitter, die_after_collision),
-  CGETSET_ADD(emitter, persist),
-  CGETSET_ADD(emitter, persist_var),
-  CGETSET_ADD(emitter, warp_mask),
-  MIST_FUNC_DEF(emitter, emit, 1),
-  MIST_FUNC_DEF(emitter, step, 1),
-  MIST_FUNC_DEF(emitter, draw, 1)
-};
-
 JSC_GETSET(transform, pos, vec3)
 JSC_GETSET(transform, scale, vec3)
 JSC_GETSET(transform, rotation, quat)
@@ -1543,10 +1531,21 @@ JSC_CCALL(transform_direction,
   return vec32js(HMM_QVRot(js2vec3(argv[0]), t->rotation));
 )
 
+JSC_CCALL(transform_phys2d,
+  transform *t = js2transform(self);
+  HMM_Vec2 v = js2vec2(argv[0]);
+  float av = js2number(argv[1]);
+  float dt = js2number(argv[2]);
+  transform_move(t, (HMM_Vec3){v.x*dt,v.y*dt,0});
+  HMM_Quat rot = HMM_QFromAxisAngle_LH((HMM_Vec3){0,0,1}, av*dt);
+  t->rotation = HMM_MulQ(t->rotation, rot);
+)
+
 static const JSCFunctionListEntry js_transform_funcs[] = {
   CGETSET_ADD(transform, pos),
   CGETSET_ADD(transform, scale),
   CGETSET_ADD(transform, rotation),
+  MIST_FUNC_DEF(transform, phys2d, 3),
   MIST_FUNC_DEF(transform, move, 1),
   MIST_FUNC_DEF(transform, rotate, 2),
   MIST_FUNC_DEF(transform, angle, 1),
@@ -2399,18 +2398,6 @@ JSC_SCALL(os_make_model,
   return v;
 )
 
-JSC_CCALL(os_make_emitter,
-  emitter *e = make_emitter();
-  ret = emitter2js(e);
-  sg_buffer *b = malloc(sizeof(*b));
-  *b = sg_make_buffer(&(sg_buffer_desc) {
-    .type = SG_BUFFERTYPE_STORAGEBUFFER,
-    .size = 4,
-    .usage = SG_USAGE_STREAM
-  });
-  js_setpropstr(ret, "buffer", sg_buffer2js(b));
-)
-
 JSC_CCALL(os_make_buffer,
   int type = js2number(argv[1]);
   float *b = malloc(sizeof(float)*js_arrlen(argv[0]));
@@ -2590,7 +2577,6 @@ static const JSCFunctionListEntry js_os_funcs[] = {
   MIST_FUNC_DEF(os, make_font, 2),
   MIST_FUNC_DEF(os, make_model, 1),
   MIST_FUNC_DEF(os, make_transform, 0),
-  MIST_FUNC_DEF(os, make_emitter, 0),
   MIST_FUNC_DEF(os, make_buffer, 1),
   MIST_FUNC_DEF(os, make_line_prim, 4),
   MIST_FUNC_DEF(os, make_cylinder, 2),
@@ -2623,7 +2609,6 @@ void ffi_load() {
   QJSCLASSPREP_FUNCS(gameobject);
   QJSCLASSPREP_FUNCS(transform);
   QJSCLASSPREP_FUNCS(dsp_node);
-  QJSCLASSPREP_FUNCS(emitter);
   QJSCLASSPREP_FUNCS(warp_gravity);
   QJSCLASSPREP_FUNCS(warp_damp);
   QJSCLASSPREP_FUNCS(texture);

source/engine/particle.c

@@ -1,123 +0,0 @@
-#include "particle.h"
-#include "stb_ds.h"
-#include "render.h"
-#include "2dphysics.h"
-#include "math.h"
-#include "log.h"
-
-emitter *make_emitter() {
-  emitter *e = calloc(sizeof(*e),1);
-  
-  e->max = 20;
-  arrsetcap(e->particles, 10);
-  for (int i = 0; i < arrlen(e->particles); i++)
-    e->particles[i].life = 0;
-    
-  e->life = 10;
-  e->tte = lerp(e->explosiveness, e->life/e->max, 0);
-  e->scale = 1;
-  e->speed = 20;
-  e->color = (HMM_Vec4){1,1,1,1};
-  
-  return e;
-}
-
-void emitter_free(emitter *e)
-{
-  arrfree(e->particles);
-  arrfree(e->verts);
-  free(e);
-}
-
-/* Variate a value around variance. Variance between 0 and 1. */
-
-float variate(float val, float variance)
-{
-  return val + val*(frand(variance)-(variance/2));
-}
-
-int emitter_spawn(emitter *e, transform *t)
-{
-  if (arrlen(e->particles) == e->max) return 0;
-  particle p = {0};
-  p.life = e->life;
-  p.pos = (HMM_Vec4){t->pos.x,t->pos.y,t->pos.z,0};
-  HMM_Vec3 up = transform_direction(t, vFWD);
-  float newan = (frand(e->divergence)-(e->divergence/2))*HMM_TurnToRad;
-  HMM_Vec2 v2n = HMM_V2Rotate((HMM_Vec2){0,1}, newan);
-  HMM_Vec3 norm = (HMM_Vec3){v2n.x, v2n.y,0};
-  p.v = HMM_MulV4F((HMM_Vec4){norm.x,norm.y,norm.z,0}, variate(e->speed, e->variation));
-  p.angle = e->tumble;
-  p.av = e->tumble_rate;
-  p.scale = variate(e->scale*t->scale.x, e->scale_var);
-  arrput(e->particles,p);
-  return 1;
-}
-
-void emitter_emit(emitter *e, int count, transform *t)
-{
-  for (int i = 0; i < count; i++)
-    emitter_spawn(e, t);
-}
-
-void emitter_draw(emitter *e, sg_buffer *b)
-{
-  if (arrlen(e->particles) == 0) return;
-  arrsetlen(e->verts, arrlen(e->particles));
-  for (int i = 0; i < arrlen(e->particles); i++) {
-    if (e->particles[i].time >= e->particles[i].life) continue;
-    particle *p = e->particles+i;
-    e->verts[i].pos = p->pos.xy;
-    e->verts[i].angle = p->angle;
-    e->verts[i].scale = p->scale;
-    if (p->time < e->grow_for)
-      e->verts[i].scale = lerp(p->time/e->grow_for, 0, p->scale);
-    else if (p->time > (p->life - e->shrink_for))
-      e->verts[i].scale = lerp((p->time-(p->life-e->shrink_for))/e->shrink_for, p->scale, 0);
-    e->verts[i].color = p->color;
-  }
-
-  sg_range verts;
-  verts.ptr = e->verts;
-  verts.size = sizeof(*e->verts)*arrlen(e->verts);
-  if (sg_query_buffer_will_overflow(*b, verts.size)) {
-    sg_destroy_buffer(*b);
-    *b = sg_make_buffer(&(sg_buffer_desc){
-      .size = verts.size,
-      .type = SG_BUFFERTYPE_STORAGEBUFFER,
-      .usage = SG_USAGE_STREAM
-    });
-  }
-    
-  sg_append_buffer(*b, &verts);
-}
-
-void emitter_step(emitter *e, double dt, transform *t) {
-  HMM_Vec4 g_accel = HMM_MulV4F((HMM_Vec4){cpSpaceGetGravity(space).x, cpSpaceGetGravity(space).y, 0, 0}, dt);
-  
-  for (int i = 0; i < arrlen(e->particles); i++) {
-    if (e->particles[i].time >= e->particles[i].life) continue;
-  
-    if (e->warp_mask & gravmask)
-      e->particles[i].v = HMM_AddV4(e->particles[i].v, g_accel);
-      
-    e->particles[i].pos = HMM_AddV4(e->particles[i].pos, HMM_MulV4F(e->particles[i].v, dt));
-    e->particles[i].angle += e->particles[i].av*dt;
-    e->particles[i].time += dt;
-    e->particles[i].color = e->color;
-    //e->particles[i].color = sample_sampler(&e->color, e->particles[i].time/e->particles[i].life);
-    e->particles[i].scale = e->scale;
-  
-   if (e->particles[i].time >= e->particles[i].life)
-     arrdelswap(e->particles, i);
-//   else if (query_point(e->particles[i].pos.xy))
-//     arrdelswap(e->particles,i);
-  }
-
-  e->tte-=dt;
-  float step = lerp(e->explosiveness, e->life/e->max,0);
-  while (e->tte <= 0) {
-    e->tte += step;
-    if (!emitter_spawn(e, t)) break;
-  }
-}

source/engine/particle.h

@@ -1,74 +0,0 @@
-#ifndef PARTICLE_H
-#define PARTICLE_H
-
-#include "HandmadeMath.h"
-#include "warp.h"
-#include "transform.h"
-#include "texture.h"
-#include "anim.h"
-#include "gameobject.h"
-#include "render.h"
-
-typedef struct particle {
-  HMM_Vec4 pos;
-  HMM_Vec4 v; /* velocity */
-  float angle;
-  float av; /* angular velocity */
-  float scale;
-  double time;
-  double life;
-  HMM_Vec4 color;
-} particle;
-
-#define SPRAY 0
-#define CLOUD 1
-#define MESH 2
-
-typedef struct par_vert {
-  HMM_Vec2 pos;
-  float angle;
-  float scale;
-  HMM_Vec4 color;
-} par_vert;
-
-typedef struct emitter {
-  struct particle *particles;
-  par_vert *verts;
-  HMM_Vec3 *mesh; /* list of points to optionally spawn from */
-  HMM_Vec3 *norm; /* norm at each point */
-  int type; /* spray, cloud, or mesh */
-  float explosiveness; /* 0 for a stream, 1 for all at once. Range of values allowed. */
-  int max; /* number of particles */
-  double life; /* how long a particle lasts */
-  double life_var;
-  /* SPRAY PARTICLE GEN */
-  float speed; /* initial speed of particle */
-  float variation; /* variation on speed */
-  float divergence; /* angular degree of variation from emitter normal, up to 1 */
-  float tumble; /* amount of random rotation of particles */
-  float tumble_rate; /* tumble rotation */
-  HMM_Vec4 color; /* color over particle lifetime */
-  float scale;
-  float scale_var;
-  float grow_for; /* seconds to grow from small until scale */
-  float shrink_for; /* seconds to shrink to small prior to its death */
-  /* ROTATION AND COLLISION */
-  int collision_mask; /* mask for collision */
-  float bounce; /* bounce back after collision */
-  /* PARTICLE SPAWN */
-  int die_after_collision;
-  float persist; /* how long to linger after death */
-  float persist_var;
-  /* TRAILS */
-  warpmask warp_mask;
-  double tte; /* time to emit */ 
-} emitter;
-
-emitter *make_emitter();
-void emitter_free(emitter *e);
-
-void emitter_emit(emitter *e, int count, transform *t);
-void emitter_step(emitter *e, double dt, transform *t);
-void emitter_draw(emitter *e, sg_buffer *b);
-
-#endif

source/engine/render.c

@@ -5,7 +5,6 @@
 #include "font.h"
 #include "gameobject.h"
 #include "log.h"
-#include "particle.h"
 #include "window.h"
 #include "model.h"
 #include "stb_ds.h"

source/engine/yugine.c

@@ -7,7 +7,6 @@
 #include "resources.h"
 #include "spline.h"
 #include <stdio.h>
-#include "particle.h"
 #include "simplex.h"
 #include <wctype.h>