raycaster-demo/main.lua

67 lines
No EOL
2.7 KiB
Lua

import "CoreLibs/graphics"
import "CoreLibs/ui"
local function clamp(value, min, max)
return math.max(math.min(value, max), min)
end
local function make_player(x, y, width, height, screen)
local crankPosition = playdate.getCrankPosition()
local player = { position={ x=x, y=y, theta=crankPosition}, width=width, height=height, screen=screen }
player.draw = function(self)
local w, h, transform = self.width / 2, self.height / 2, playdate.geometry.affineTransform.new()
local polygon = playdate.geometry.polygon.new(-w,-0.5*h, -w,0.5*h, w,0, -w,-0.5*h)
transform:translate(self.position.x, self.position.y)
transform:rotate(self.position.theta, self.position.x, self.position.y)
local transformedPolygon = transform:transformedPolygon(polygon)
playdate.graphics.drawPolygon(transformedPolygon)
end
player.translate = function(self, y_amount)
local w, h, theta_rad = self.width / 2, self.height / 2, math.rad(self.position.theta)
local new_x = self.position.x + (y_amount * math.cos(theta_rad))
local new_y = self.position.y + (y_amount * math.sin(theta_rad))
self.position.x = clamp(new_x, w, self.screen.width - w)
self.position.y = clamp(new_y, h, self.screen.height - h)
end
player.rotate = function(self, degrees)
local new_theta = self.position.theta + degrees
if new_theta < 0 then new_theta = new_theta + 360 end
if new_theta > 360 then new_theta = new_theta - 360 end
self.position.theta = new_theta
end
player.handle_crank = function(self)
local change, _acceleratedChange = playdate.getCrankChange()
self:rotate(change)
end
player.size = function(self, amount)
self.width = clamp(self.width + amount, 2, 80)
self.height = clamp(self.height + amount, 2, 80)
local w, h = self.width / 2, self.height / 2
self.position.x = clamp(self.position.x, w, self.screen.width - w)
self.position.y = clamp(self.position.y, h, self.screen.height - h)
end
return player
end
local screen = { width=400, height=240 }
local player = make_player(screen.width / 2, screen.height / 2, 20, 30, screen)
function playdate.update()
playdate.graphics.clear()
if playdate.isCrankDocked() then playdate.ui.crankIndicator:draw() end
if playdate.buttonIsPressed(playdate.kButtonUp) then player:translate(10) end
if playdate.buttonIsPressed(playdate.kButtonDown) then player:translate(-10) end
if playdate.buttonIsPressed(playdate.kButtonLeft) then player:size(2) end
if playdate.buttonIsPressed(playdate.kButtonRight) then player:size(-2) end
player:handle_crank()
player:draw()
end