foss-mmo/game.scm
2024-05-22 17:40:23 -04:00

416 lines
13 KiB
Scheme

;;; Copyright (C) 2024 David Thompson <dave@spritely.institute>
;;;
;;; Licensed under the Apache License, Version 2.0 (the "License");
;;; you may not use this file except in compliance with the License.
;;; You may obtain a copy of the License at
;;;
;;; http://www.apache.org/licenses/LICENSE-2.0
;;;
;;; Unless required by applicable law or agreed to in writing, software
;;; distributed under the License is distributed on an "AS IS" BASIS,
;;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
;;; See the License for the specific language governing permissions and
;;; limitations under the License.
;;; Commentary:
;;;
;;; Example game showing off several common game programming things.
;;;
;;; Code:
(use-modules (dom canvas)
(dom document)
(dom element)
(dom event)
(dom image)
(dom media)
(dom window)
(game actors)
(game level)
(game levels level-1)
(game levels level-2)
(game levels level-3)
(game levels level-4)
(game tileset)
(goblins core)
(hoot bytevectors)
(hoot ffi)
(hoot hashtables)
(ice-9 match)
(local-storage)
(math)
(math rect)
(math vector))
(define game-width 320.0)
(define game-height 240.0)
(define level-width (inexact->exact (floor (/ game-width tile-width))))
(define level-height (inexact->exact (floor (/ game-height tile-height))))
(define *canvas-scale* 0.0)
(define *canvas-width* 0)
(define *canvas-height* 0)
;; Assets
(define tileset
(make-tileset (make-image "assets/images/cirkoban.png")
320 240
(inexact->exact tile-width)
(inexact->exact tile-height)))
(define* (load-sound-effect name #:key (volume 0.25))
(let ((audio (make-audio (string-append "assets/sounds/" name ".wav"))))
(set-media-volume! audio volume)
audio))
(define audio:bump (load-sound-effect "bump"))
(define audio:push (load-sound-effect "push"))
(define audio:undo (load-sound-effect "undo"))
(define audio:no (load-sound-effect "no"))
(define audio:exit (load-sound-effect "exit"))
(define audio:pickup (load-sound-effect "pickup"))
(define audio:die (load-sound-effect "die"))
;; Game state
(define *state* #f)
(define *actormap* (make-whactormap))
(define (call-with-goblins thunk)
(actormap-churn-run! *actormap* thunk))
(define-syntax-rule (with-goblins body ...)
(call-with-goblins (lambda () body ...)))
(define levels
(vector
load-level-1
load-level-2
load-level-3
load-level-4))
(define *level-idx* #f)
(define *gems* #f)
(define *level* #f)
;; Latest representation of all actors in level
(define *objects* #f)
(define *snapshots* '())
(define (clear-snapshots!)
(set! *snapshots* '()))
(define (save-snapshot!)
(set! *snapshots* (cons (copy-whactormap *actormap*) *snapshots*)))
(define (rollback-snapshot!)
(match *snapshots*
(() (media-play audio:no))
((snapshot . older-snapshots)
(set! *actormap* snapshot)
(set! *snapshots* older-snapshots)
(media-play audio:undo))))
(define (sort lst compare)
(match lst
(() '())
((_) lst)
(_
;; Insertion sort because I am lazy!
(let ((vec (list->vector lst)))
(let outer ((i 1))
(when (< i (vector-length vec))
(let inner ((j i))
(when (> j 0)
(let ((a (vector-ref vec j))
(b (vector-ref vec (1- j))))
(when (compare a b)
(vector-set! vec j b)
(vector-set! vec (1- j) a)
(inner (1- j))))))
(outer (1+ i))))
(vector->list vec)))))
(define (filter-map proc lst)
(let lp ((lst lst))
(match lst
(() '())
((head . tail)
(let ((head* (proc head)))
(if head*
(cons head* (lp tail))
(lp tail)))))))
(define (update-objects!)
(set! *objects*
;; z-sort the list so we render in the correct order. Then
;; convert tile positions to vec2s of pixel coordinates for
;; more efficient rendering.
(map (match-lambda
((type #(x y _) . properties)
`(,type ,(vec2 (* x tile-width) (* y tile-height)) ,@properties)))
(sort ($ (level-actor *level*) 'describe)
(lambda (a b)
(match a
((_ #(_ _ az) . _)
(match b
((_ #(_ _ bz) . _)
(<= az bz))))))))))
(define (collected-gem? idx)
(not (memq idx *gems*)))
(define (load-level! idx)
(set! *state* 'play)
(set! *actormap* (make-whactormap))
(clear-snapshots!)
(with-goblins
(set! *level* ((vector-ref levels idx) (collected-gem? idx)))
(update-objects!)))
(define (next-level!)
(let ((idx (+ *level-idx* 1)))
(pk 'next-level idx)
(set! *level-idx* idx)
(if (< idx (vector-length levels))
(begin
(save-game!)
(load-level! idx))
(set! *state* 'win))))
;; Auto-save/load to local storage.
(define (save-game!)
(pk 'save)
(local-storage-set! "cirkoban-save"
(call-with-output-string
(lambda (port)
(write (list *level-idx* *gems*) port)))))
(define (load-game!)
(let ((saved
(match (local-storage-ref "cirkoban-save")
("" '(0 ())) ; initial save state
(str (call-with-input-string str read)))))
(match saved
((idx gems)
(set! *level-idx* idx)
(set! *gems* gems)
(pk 'load *level-idx*)
(load-level! *level-idx*)))))
(define (reset-game!)
(set! *level-idx* 0)
(save-game!)
(load-level! 0))
;; Update loop
(define (move-player dir)
(define (do-move)
(with-goblins
(let ((player (level-player *level*)))
(if ($ player 'alive?)
(begin
($ player 'move dir)
($ (level-actor *level*) 'tick)
;; TODO: Need a better way to receive events to play sounds
;; and emit particles and stuff so any actor can trigger
;; events.
(let ((result
(match ($ player 'event)
(('bump)
(media-play audio:bump)
#f)
(('push)
(media-play audio:push)
#f)
(('exit)
(media-play audio:exit)
'next-level)
(('die)
(media-play audio:die)
#f)
(('gem)
(media-play audio:pickup)
;; TODO: Maybe show a little achievement popup when all gems
;; are collected?
(set! *gems* (cons *level-idx* *gems*))
#f)
(_ #f))))
(update-objects!)
(save-snapshot!)
result))
(begin
(media-play audio:no)
#f)))))
(when (eq? (do-move) 'next-level)
(next-level!)))
(define dt (/ 1000.0 60.0)) ; aim for updating at 60Hz
(define (update)
;; TODO: what kind of work do we need to do each frame?
(timeout update-callback dt))
(define update-callback (procedure->external update))
;; Render loop
(define number->string*
(let ((cache (make-eq-hashtable))) ; assuming fixnums only
(lambda (x)
(or (hashtable-ref cache x)
(let ((str (number->string x)))
(hashtable-set! cache x str)
str)))))
(define (draw-player pos)
(draw-tile context tileset 0 (vec2-x pos) (vec2-y pos)))
(define (draw-exit pos)
(draw-tile context tileset 27 (vec2-x pos) (vec2-y pos)))
(define (draw-wire-state pos state)
(let ((x (vec2-x pos))
(y (vec2-y pos)))
(match state
('electron-head
(draw-tile context tileset 4 x y))
('electron-tail
(draw-tile context tileset 5 x y))
(_ #f))))
(define (draw-wall pos type)
(draw-wire-state pos type))
(define (draw-block pos type)
(let ((x (vec2-x pos))
(y (vec2-y pos)))
(match type
('crate (draw-tile context tileset 29 x y))
(_ (draw-tile context tileset 3 x y)))
(draw-wire-state pos type)))
(define (draw-clock-emitter pos)
(draw-tile context tileset 48 (vec2-x pos) (vec2-y pos)))
(define (draw-floor-switch pos on?)
(draw-tile context tileset (if on? 25 24) (vec2-x pos) (vec2-y pos)))
(define (draw-gem pos)
(draw-tile context tileset 28 (vec2-x pos) (vec2-y pos)))
(define (draw-gate pos open?)
(draw-tile context tileset (if open? 46 45) (vec2-x pos) (vec2-y pos)))
(define (draw-logic-gate pos state id)
(let ((x (vec2-x pos))
(y (vec2-y pos)))
(draw-tile context tileset 2 x y)
(draw-tile context tileset id x y)
(draw-wire-state pos state)))
(define (draw-electric-switch pos on?)
(draw-tile context tileset (if on? 7 6) (vec2-x pos) (vec2-y pos)))
(define (draw-electron-warp pos state)
(draw-tile context tileset 71 (vec2-x pos) (vec2-y pos))
(draw-wire-state pos state))
(define (draw-object obj)
(match obj
(#f #f)
(('player pos) (draw-player pos))
(('exit pos) #t) ; drawn via background
(('wall pos type) (draw-wall pos type))
(('block pos type) (draw-block pos type))
(('clock-emitter pos) #t) ; drawn via background
(('floor-switch pos on?) (draw-floor-switch pos on?))
(('gem pos) (draw-gem pos))
(('gate pos open?) (draw-gate pos open?))
(('and-gate pos state) (draw-logic-gate pos state 42))
(('or-gate pos state) (draw-logic-gate pos state 43))
(('xor-gate pos state) (draw-logic-gate pos state 44))
(('electric-switch pos on?) (draw-electric-switch pos on?))
(('electron-warp pos state) (draw-electron-warp pos state))))
(define (draw-background)
(let ((bg (level-background *level*))
(k (* level-width level-height)))
(do ((i 0 (1+ i)))
((= i k))
(let* ((tile (vector-ref bg i))
(pos (level-tile-position tile))
(id (level-tile-id tile)))
(draw-tile context tileset id (vec2-x pos) (vec2-y pos))))))
(define (draw-level)
(draw-background)
(for-each draw-object *objects*))
(define (draw-win)
(set-fill-color! context "#x000000")
(fill-text context "OMG YOU DID IT WOW CONGRATS" 32.0 120.0))
(define (draw prev-time)
(clear-rect context 0.0 0.0 *canvas-width* *canvas-height*)
(set-transform! context 1.0 0.0 0.0 1.0 0.0 0.0)
(set-scale! context *canvas-scale* *canvas-scale*)
(match *state*
('play (draw-level))
('win (draw-win)))
(request-animation-frame draw-callback))
(define draw-callback (procedure->external draw))
;; Input
(define key:left "ArrowLeft")
(define key:right "ArrowRight")
(define key:down "ArrowDown")
(define key:up "ArrowUp")
(define key:confirm "Enter")
(define key:undo "KeyZ")
(define (on-key-down event)
(let ((key (keyboard-event-code event)))
(pk 'key-down key)
(match *state*
('play
(cond
((string=? key key:left)
(move-player 'left))
((string=? key key:right)
(move-player 'right))
((string=? key key:up)
(move-player 'up))
((string=? key key:down)
(move-player 'down))
((string=? key key:undo)
(rollback-snapshot!)
(with-goblins (update-objects!)))
;; REMOVE BEFORE RELEASE!!!!
((string=? key key:confirm)
(next-level!))))
('win
(cond
((string=? key key:confirm)
(reset-game!)))))))
;; Canvas and event loop setup
(define canvas (get-element-by-id "canvas"))
(define context (get-context canvas "2d"))
(define (resize-canvas)
(let* ((win (current-window))
(w (window-inner-width win))
(h (window-inner-height win))
(gw (inexact->exact game-width))
(gh (inexact->exact game-height))
(scale (max (min (quotient w gw) (quotient h gh)) 1))
(cw (* gw scale))
(ch (* gh scale)))
(set-element-width! canvas cw)
(set-element-height! canvas ch)
(set-image-smoothing-enabled! context 0)
(set! *canvas-scale* (exact->inexact scale))
(set! *canvas-width* (* game-width *canvas-scale*))
(set! *canvas-height* (* game-height *canvas-scale*))
(pk 'resize-canvas *canvas-scale* *canvas-width* *canvas-height*)))
(set-element-width! canvas (inexact->exact game-width))
(set-element-height! canvas (inexact->exact game-height))
(add-event-listener! (current-window) "resize"
(procedure->external (lambda (_) (resize-canvas))))
(add-event-listener! (current-document) "keydown"
(procedure->external on-key-down))
(resize-canvas)
(request-animation-frame draw-callback)
(timeout update-callback dt)
(load-game!)