Drawable:set_draw_order_modifier
Sets how the draw order of this Drawable is computed.
When the modifier is set to "replace", the DrawOrder component on the entity is ignored. The draw order is entirely determined by the value parameter specified in this function call.
When the modifier is set to "add", the value parameter specified in this function call is added to the draw order specified by the DrawOrder component on the entity. If the entity has no DrawOrder component, the value parameter is used as-is.
As a rule of thumb, you should use:
- DrawOrder components to order entities relative to each other.
"add"modifiers to order drawables within an entity.- (rarely)
"replace"modifiers to decouple a drawable from its entity’s draw order entirely.
Usage
drawable:set_draw_order_modifier(modifier, value)
Arguments
| Name | Type | Description |
|---|---|---|
modifier | "add" or "replace" | Modifier type to apply to the draw order. |
value | number | Value used when computing the draw order. |
Examples
local ecs = crystal.ECS:new();
local entity = ecs:spawn(crystal.Entity);
entity:add_component(crystal.Sprite, crystal.assets.get("wild_boar.png"));
local health_bar = entity:add_component(crystal.WorldWidget, HealthBar:new());
health_bar:set_draw_order_modifier("replace", math.huge); -- Draw health bar in front of everything
local ecs = crystal.ECS:new();
local entity = ecs:spawn(crystal.Entity);
local body = entity:add_component(crystal.Sprite, crystal.assets.get("human_body.png"));
local head = entity:add_component(crystal.Sprite, crystal.assets.get("human_head.png"));
local weapon = entity:add_component(crystal.Sprite, crystal.assets.get("sword.png"));
body:set_draw_order_modifier("add", 0);
head:set_draw_order_modifier("add", 0.1); -- Head draws in front of body
weapon:set_draw_order_modifier("add", 0.2); -- Weapon draws in front of head