2d-camera.nelua

--[[ This Source Code Form is subject to the terms of the Mozilla Public
     License, v. 2.0. If a copy of the MPL was not distributed with this
     file, You can obtain one at https://mozilla.org/MPL/2.0/. ]]

-- This code is based on the "2d camera" example by raysan5,
-- available at: https://github.com/raysan5/raylib/blob/master/examples/core/core_2d_camera.c

-- Note: unfortunately my controller doens't worked on my SO, so, I can't really test this

require 'raylib'

local MAX_BUILDINGS: integer <comptime> = 100

-- [[ Initialization [[
local screen_width: integer <comptime> = 800
local screen_height: integer <comptime> = 450

Raylib.InitWindow(screen_width, screen_height, "raylib-nelua [core] example - 2d camera")

local player: Rectangle = { 400, 280, 40, 40 }
local buildings: [MAX_BUILDINGS]Rectangle;
local build_colors: [MAX_BUILDINGS]Color;

local spacing: integer = 0

for i: integer = 0, < MAX_BUILDINGS do
  buildings[i].width = Raylib.GetRandomValue(50, 200)
  buildings[i].height = Raylib.GetRandomValue(100, 800)
  buildings[i].y = screen_height - 130 - buildings[i].height
  buildings[i].x = -6000 + spacing

  spacing = spacing + buildings[i].width

  build_colors[i] = { Raylib.GetRandomValue(200, 240), Raylib.GetRandomValue(200, 240), Raylib.GetRandomValue(200, 250), 255 }
end

local camera: Camera2D = {
  target = { player.x + 20, player.y + 20 },
  offset = { screen_width / 2, screen_height / 2 },
  rotation = 0,
  zoom = 1
}

Raylib.SetTargetFPS(60); -- Set our game to run at 60 frames-per-second
-- ]] Initialization ]]

-- [[ Main game loop [[
while not Raylib.WindowShouldClose() do -- Detect window close button or ESC key
  -- [[ Update [[
  -- Player movement
  if Raylib.IsKeyDown(KeyboardKey.KEY_RIGHT) then
    player.x = player.x + 2
  elseif Raylib.IsKeyDown(KeyboardKey.KEY_LEFT) then
    player.x = player.x - 2
  end

  -- Camera target follows player
  camera.target = { player.x + 20, player.y + 20 }

  -- Camera rotation controls
  if Raylib.IsKeyDown(KeyboardKey.KEY_A) then
    camera.rotation = camera.rotation - 1
  elseif Raylib.IsKeyDown(KeyboardKey.KEY_S) then
    camera.rotation = camera.rotation + 1
  end

  -- Limit camera rotation to 80 degrees (-40 to 40)
  if camera.rotation > 40 then
    camera.rotation = 40
  elseif camera.rotation < -40  then
    camera.rotation = -40
  end

  -- Camera zoom controls
  camera.zoom = camera.zoom + (@number)(Raylib.GetMouseWheelMove() * 0.05)

  if camera.zoom > 3 then
    camera.zoom = 3
  elseif camera.zoom < 0.1 then
    camera.zoom = 0.1
  end

  -- Camera reset (zoom and rotation)
  if Raylib.IsKeyPressed(KeyboardKey.KEY_R) then
    camera.zoom = 1
    camera.rotation = 0
  end
  -- ]] Update ]]

  -- [[ Draw [[
  Raylib.BeginDrawing()
  do
    Raylib.ClearBackground(RAYWHITE)

    Raylib.BeginMode2D(camera)
    do
      Raylib.DrawRectangle(-6000, 320, 13000, 8000, DARKGRAY)

      for i: integer = 0, < MAX_BUILDINGS do
        Raylib.DrawRectangleRec(buildings[i], build_colors[i])
      end

      Raylib.DrawRectangleRec(player, RED)

      Raylib.DrawLine(camera.target.x, -screen_height * 10, camera.target.x, screen_height * 10, GREEN)
      Raylib.DrawLine(-screen_width * 10, camera.target.y, screen_width * 10, camera.target.y, GREEN)
    end
    Raylib.EndMode2D()

    Raylib.DrawText("SCREEN AREA", 640, 10, 20, RED)

    Raylib.DrawRectangle(0, 0, screen_width, 5, RED)
    Raylib.DrawRectangle(0, 5, 5, screen_height - 10, RED)
    Raylib.DrawRectangle(screen_width - 5, 5, 5, screen_height - 10, RED)
    Raylib.DrawRectangle(0, screen_height - 5, screen_width, 5, RED)

    Raylib.DrawRectangle( 10, 10, 250, 113, Raylib.Fade(SKYBLUE, 0.5))
    Raylib.DrawRectangleLines( 10, 10, 250, 113, BLUE)

    Raylib.DrawText("Free 2d camera controls:", 20, 20, 10, BLACK)
    Raylib.DrawText("- Right/Left to move Offset", 40, 40, 10, DARKGRAY)
    Raylib.DrawText("- Mouse Wheel to Zoom in-out", 40, 60, 10, DARKGRAY)
    Raylib.DrawText("- A / S to Rotate", 40, 80, 10, DARKGRAY)
    Raylib.DrawText("- R to reset Zoom and Rotation", 40, 100, 10, DARKGRAY)
  end
  Raylib.EndDrawing()
   -- ]] Draw ]]
end
-- ]] Main game loop ]]

-- [ De-Initialization [
Raylib.CloseWindow() -- Close window and OpenGL context
-- ] De-Initialization ]