particle spawn shapes

1 files changed, 22 insertions, 1 deletions

diff --git a/src/objs/specks.lua b/src/objs/specks.lua
index 7bd3c78..5044c9c 100644
--- a/src/objs/specks.lua
+++ b/src/objs/specks.lua
@@ -1,6 +1,24 @@
 Speck_Sys = {}
 Speck_Sys.__index = Speck_Sys
 
+function speck_shape_rectangle(speck_sys)
+  local w = (speck_sys.spawn_width or 0) / 2
+  local h = (speck_sys.spawn_height or 0) / 2
+
+  return randf_range(-w, w), randf_range(-h, h)
+end
+
+function speck_shape_point(speck_sys)
+  return 0, 0
+end
+
+function speck_shape_circle(speck_sys)
+  local angle = randf_range(0, math.pi * 2)
+  local r = speck_sys.spawn_radius or 0
+  r = r * lmath.random()
+  return r*math.cos(angle), r*math.sin(angle)
+end
+
 function Speck_Sys.new()
   local self = setmetatable({}, Speck_Sys)
 
@@ -20,6 +38,8 @@ function Speck_Sys.new()
   self.free_ids = {}
   self.free_ids_size = 0
 
+  self.spawn_shape = speck_shape_point
+
   self.spawn_amount_min = 1
   self.spawn_amount_max = 1
 
@@ -79,7 +99,8 @@ function Speck_Sys:spawn_particles()
 
     data.alive[id] = true
 
-    data.pos[id] = { x = self.x, y = self.y }
+    local offx, offy = self.spawn_shape(self)
+    data.pos[id] = { x = self.x + offx, y = self.y + offy }
     data.vel[id] = { x = self.initial_velx, y = self.initial_vely }
 
     local beta = self.spread * math.pi / 180