implemented smooth camera & scrolling w/ mousewheel

camera.lua

@@ -1,34 +1,45 @@
 local Vec3 = require "lib/vec3"
 local tree = require "lib/tree"
 
+local EPSILON = 0.001
+
 --- @class (exact) Camera
---- @field target Vec3
+--- @field position Vec3
+--- @field velocity Vec3
 --- @field speed number
 --- @field pixelsPerMeter integer
 local camera = {
-    target = Vec3 {},
+    position = Vec3 {},
+    velocity = Vec3 {},
     speed = 5,
     pixelsPerMeter = 100
 }
 
+---@todo Отрефакторить и вынести кнопки управления в controls, не должно быть таких ужасных проверок
 function camera:update(dt)
     local ws = tree.instance().wheelscroll
     if ws.delta:length() > 0 then
-        local worldDelta = ws.delta * (1 / self.pixelsPerMeter)
-        self.target = self.target + worldDelta
-        return
+        local worldDelta = ws.delta:scale(1 / self.pixelsPerMeter):scale(dt):scale(self.speed)
+        self.velocity = self.velocity + worldDelta
+    elseif love.keyboard.isDown("w") or love.keyboard.isDown("a") or love.keyboard.isDown("s") or love.keyboard.isDown("d") then
+        if love.keyboard.isDown("w") then self.velocity = self.velocity + Vec3({ 0, -1 }) end
+        if love.keyboard.isDown("a") then self.velocity = self.velocity + Vec3({ -1 }) end
+        if love.keyboard.isDown("s") then self.velocity = self.velocity + Vec3({ 0, 1 }) end
+        if love.keyboard.isDown("d") then self.velocity = self.velocity + Vec3({ 1 }) end
+        self.velocity = (self.velocity:normalize() or Vec3 {}):scale(self.speed):scale(dt)
     end
 
-    if love.keyboard.isDown("w") then self.target = self.target + Vec3({ 0, -dt * self.speed }) end
-    if love.keyboard.isDown("a") then self.target = self.target + Vec3({ -dt * self.speed }) end
-    if love.keyboard.isDown("s") then self.target = self.target + Vec3({ 0, dt * self.speed }) end
-    if love.keyboard.isDown("d") then self.target = self.target + Vec3({ dt * self.speed }) end
+    self.position = self.position + self.velocity
+    self.velocity = self.velocity -
+        self.velocity * 5 *
+        dt -- магическая формула, которая означает "экспоненциально замедлиться до нуля"
+    if self.velocity:length() < EPSILON then self.velocity = Vec3 {} end
 end
 
 function camera:attach()
     love.graphics.push()
     love.graphics.scale(self.pixelsPerMeter)
-    love.graphics.translate(-self.target.x, -self.target.y)
+    love.graphics.translate(-self.position.x, -self.position.y)
 end
 
 function camera:detach()

lib/utils.lua

@@ -16,4 +16,8 @@ function P.generateList(count, generator)
     return xs
 end
 
+function P.sign(number)
+    return (number > 0 and 1) or (number == 0 and 0) or -1
+end
+
 return P

lib/wheelscroll.lua

@@ -1,22 +1,22 @@
 local Vec3 = require "lib/vec3"
-local MIDDLE_BUTTON = 3
 
---- @class (exact) WheelScroll
---- @field x number
---- @field y number
+--- @class WheelScroll
+--- @field pos Vec3 | nil
 --- @field delta Vec3
 local wheelscroll = {
-    x = 0.0,
-    y = 0.0,
+    pos = nil,
     delta = Vec3 {}
 }
 
-function love.mousepressed(x, y, button)
-    if button == MIDDLE_BUTTON then
-        wheelscroll.delta = Vec3 { wheelscroll.x, wheelscroll.y } - Vec3 { x, y }
-        wheelscroll.x = x
-        wheelscroll.y = y
+function wheelscroll:update(dt)
+    if love.mouse.isDown(3) then
+        local mouseX, mouseY = love.mouse.getPosition()
+        if (wheelscroll.pos) then wheelscroll.delta = wheelscroll.pos - Vec3 { mouseX, mouseY } end
+        wheelscroll.pos = Vec3 { mouseX, mouseY }
+        return
     end
+    wheelscroll.pos = nil
+    wheelscroll.delta = Vec3 {}
 end
 
 return wheelscroll

main.lua

@@ -4,6 +4,7 @@ require "character"
 
 local camera = require 'camera'
 local Vec3 = require "lib/vec3"
+local tree = require "lib/tree"
 
 function love.conf(t)
     t.console = true
@@ -11,7 +12,7 @@ end
 
 function love.load()
     Camera = camera.new()
-    Camera.target = Vec3({})
+    Camera.position = Vec3({})
     -- PlayerFaction = Faction
 
     -- Hero1 = Character:create("Petya", 10)
@@ -27,6 +28,7 @@ end
 
 function love.update(dt)
     Camera:update(dt)
+    tree.instance().wheelscroll:update(dt)
 end
 
 function love.draw()