Adding a simple grid-based camera

8 files changed, 77 insertions, 22 deletions

diff --git a/camera.lua b/camera.lua
new file mode 100644
index 0000000..09e528b
--- /dev/null
+++ b/camera.lua
@@ -0,0 +1,38 @@
+SCREEN = vec2(128, 128)
+
+_chunk_size = vec2(102, 102)
+_chunk_size:apply(function (v) assert(v % 2 == 0) end)
+_padding = (SCREEN - _chunk_size) / 2
+assert(_chunk_size.x < SCREEN.x and _chunk_size.y < SCREEN.y)
+
+Camera = {}
+Camera.__index = Camera
+function Camera:update()
+    line(_padding.x, SCREEN.y - _padding.y, _padding.x, _padding.y, 5)
+    line(_chunk_size.x + _padding.x, SCREEN.y - _padding.y, _chunk_size.x + _padding.x, _padding.y, 5)
+    line(_padding.x, _padding.y, SCREEN.x - _padding.x, _padding.y, 5)
+    line(_padding.x, _chunk_size.y + _padding.y, SCREEN.x - _padding.x, _chunk_size.y + _padding.y, 5)
+
+    assert(self.tracking.position)
+    tracking_chunk = vec2(self.tracking.position / _chunk_size):apply(flr)
+    if (tracking_chunk == self.current_chunk) then return end
+
+    self.position = (tracking_chunk * _chunk_size) - _padding
+    self.current_chunk = tracking_chunk
+end
+
+function Camera:render(entity)
+    screen_position = (entity.sprite_position or entity.position) - self.position
+    entity:render(screen_position)
+end
+
+function Camera:new(tracking)
+    cam = setmetatable({
+        -- position = vec2(0, 0),
+        -- current_chunk = vec2(0, 0),
+        tracking = tracking
+    }, Camera)
+
+    AddUpdateHook(function (dt) cam:update() end)
+    return cam
+end
\ No newline at end of file
diff --git a/dyl.lua b/dyl.lua
index 8c5f8a2..fa0190d 100644
--- a/dyl.lua
+++ b/dyl.lua
@@ -231,6 +231,8 @@ end
 function _init()
 end
 
+_camera = Camera:new(_player)
+
 _step_t = time()
 function _update60()
     -- clear here in case we want to print to screen outside of _draw
@@ -251,8 +253,9 @@ function _update60()
 end
 
 function _draw()
-    World.sort(function(a, b)
-        return b.render_order < a.render_order 
-    end)
-    World.foreach(function(e) e:render() end)
+    -- TODO: FIX THIS
+    -- World.sort(function(a, b)
+    --     return b.render_order < a.render_order 
+    -- end)
+    World.foreach(function(e) _camera:render(e) end)
 end
\ No newline at end of file
diff --git a/dyl.p8 b/dyl.p8
index 2920e34..abc8922 100644
--- a/dyl.p8
+++ b/dyl.p8
@@ -6,6 +6,7 @@ __lua__
 #include entity.lua
 #include world.lua
 #include collisions.lua
+#include camera.lua
 #include dyl.lua
 ------------------------
 -- don't you leave    --
@@ -109,14 +110,21 @@ __gfx__
 00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
 00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
 00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-77055505000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-00000000004444005555505000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-05550555044004405000055000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-00000000040000400505050000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-55077705040550400550050000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-0000000004000a400505550000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
-05550555040000400550050000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+77055505000000000000000000009000000000000000900000900000000000000000000000000000000000000000000000000000000000000000000000000000
+00000000004444005555505000000000000000000000000000000900000000000000000000000000000000000000000000000000000000000000000000000000
+05550555044004405000055000090900000900000009900000090000000000000000000000000000000000000000000000000000000000000000000000000000
+000000000400004005050500009a9900000a90000009a900009a9000000000000000000000000000000000000000000000000000000000000000000000000000
+550777050405504005500500009aaa00009aa900009aa900009a9000000000000000000000000000000000000000000000000000000000000000000000000000
+0000000004000a400505550000444400004444000044440000444400000000000000000000000000000000000000000000000000000000000000000000000000
+05550555040000400550050004400440044004400440044004400440000000000000000000000000000000000000000000000000000000000000000000000000
 00000000000000000555550000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+000000000000000000000000000000000000a0000000000000009000000000000000000000000000000000000000000000000000000000000000000000000000
+0000000000000000000000000000900000090000000a0000000a0000000000000000000000000000000000000000000000000000000000000000000000000000
+00000000000000000000000000444400004444000044440000444400000000000000000000000000000000000000000000000000000000000000000000000000
+00000000000000000000000004400440044004400440044004400440000000000000000000000000000000000000000000000000000000000000000000000000
 __sfx__
 000100002605026050240502305022050210502105021050220500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
 00090000000502b3502b3502a35029350293503235032350313503134031330209303032030320303303034031340313403334034340373400f050340502f0502c05000000000000000000000000000000000000
diff --git a/entity.lua b/entity.lua
index 54c9769..2758071 100644
--- a/entity.lua
+++ b/entity.lua
@@ -172,9 +172,7 @@ function _get_animation_key(line_of_sight)
     return _animation_keys[n_line_of_sight.x + 2] .. "_x"
 end
 
-function Entity:render()
-    pos = self.sprite_position or self.position
-
+function Entity:render(screen_position)
     animation = self.states[self.state].animation
     if (animation == nil) then return end
     if (self.line_of_sight ~= nil) then
@@ -190,7 +188,7 @@ function Entity:render()
     reflection = animation.reflect or vec2(false, false)
     spr(
         frame,
-        self.sprite_position.x, self.sprite_position.y,
+        screen_position.x, screen_position.y,
         1, 1,
         reflection.x, reflection.y
     )
diff --git a/math.lua b/math.lua
index 4a13517..dc5ba64 100644
--- a/math.lua
+++ b/math.lua
@@ -1,13 +1,17 @@
 Vec2 = {}
+Vec2.__eq = function(a, b) return a.x == b.x and a.y == b.y end
 Vec2.__index = Vec2
 Vec2.__add = function(a, b) return vec2(a.x + b.x, a.y + b.y) end
 Vec2.__unm = function(a) return vec2(-a.x, -a.y) end
 Vec2.__sub = function(a, b) return a + (-b) end
 Vec2.__mul = function(a, b)
     if (type(b) == "number") then return vec2(a.x * b, a.y * b) end -- scalar mult
-    return a.x * b.x + a.y * b.y
+    return vec2(a.x * b.x, a.y * b.y)
+end
+Vec2.__div = function(a, b)
+    if (type(b) == "number") then return vec2(a.x / b, a.y / b) end -- scalar mult
+    return vec2(a.x / b.x, a.y / b.y)
 end
-Vec2.__div = function(a, b) return vec2(a.x / b.x, a.y / b.y) end
 Vec2.__tostring = function(a) return "(" .. fmt(a.x) .. "," .. fmt(a.y) .. ")" end
 
 function Vec2:magnitude()
@@ -17,7 +21,7 @@ end
 function Vec2:normal()
     local m = self:magnitude()
     if m == 0 then return vec2(self.x, self.y) end
-    return vec2(self.x / m, self.y / m)
+    return self / m
 end
 
 function Vec2:apply(f)
diff --git a/ui.lua b/ui.lua
deleted file mode 100644
index e69de29..0000000
--- a/ui.lua
+++ /dev/null
diff --git a/util.lua b/util.lua
index 5d31a2a..5fd41d3 100644
--- a/util.lua
+++ b/util.lua
@@ -1,5 +1,9 @@
 update_hooks = {}
 
+function AddUpdateHook(f)
+    update_hooks[#update_hooks + 1] = f
+end
+
 -- https://pico-8.fandom.com/wiki/Qsort
 function qsort(a, c, l, r)
     c, l, r = c or function(a, b) return a < b end, l or 1, r or #a
@@ -99,7 +103,7 @@ function _update_button_states(_dt)
         end
     end
 end
-update_hooks[1] = _update_button_states
+AddUpdateHook(_update_button_states)
 function button_just_pressed(id)
     return _button_states[id] == "just_pressed"
 end
\ No newline at end of file
diff --git a/world.lua b/world.lua
index 122d60a..61c6bb2 100644
--- a/world.lua
+++ b/world.lua
@@ -8,9 +8,9 @@ function _next_id()
     return i
 end
 
-function World.sort(cmp)
-    -- qsort(_World, cmp)
-end
+-- function World.sort(cmp)
+--     qsort(_World, cmp)
+-- end
 
 function World.get(id)
     return _World[id]