blob: a810e48bb78d6d7972d054ec5ce1060ffbd6fc8d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
;;; Lisparuga
;;; Copyright © 2020 David Thompson <dthompson2@worcester.edu>
;;;
;;; Lisparuga is free software: you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License as published
;;; by the Free Software Foundation, either version 3 of the License,
;;; or (at your option) any later version.
;;;
;;; Lisparuga is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with Lisparuga. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;
;; Player actor.
;;
;;; Code:
(define-module (lisparuga player)
#:use-module (chickadee math rect)
#:use-module (chickadee math vector)
#:use-module (chickadee scripting)
#:use-module (chickadee render texture)
#:use-module (lisparuga actor)
#:use-module (lisparuga asset)
#:use-module (lisparuga bullets)
#:use-module (lisparuga config)
#:use-module (lisparuga node)
#:use-module (lisparuga node-2d)
#:use-module (oop goops)
#:export (<player>
make-player
score
lives
energy
chain
chain-progress
speed
steer
start-shooting
stop-shooting
toggle-polarity
fire-homing-missiles))
(define-asset ship (load-image (scope-asset "images/player.png")))
(define-asset ship-atlas (load-tile-atlas (scope-asset "images/player.png") 24 24))
(define kill-hitbox (make-hitbox 'kill (make-rect 0.0 0.0 0.0 0.0)))
(define graze-hitbox (make-hitbox 'graze (make-rect 0.0 0.0 0.0 0.0)))
(define-class <player> (<actor>)
(score #:accessor score #:init-value 0)
(lives #:accessor lives #:init-value 2)
(energy #:accessor energy #:init-value 0)
(chain #:accessor chain #:init-value 0)
(chain-progress #:accessor chain-progress #:init-form '())
(speed #:accessor speed #:init-value 1.75)
(invincible? #:accessor invincible? #:init-value #f)
(shooting? #:accessor shooting? #:init-value #f)
(shoot-time #:accessor shoot-time #:init-value 0))
(define (make-player bullet-field)
(make <player>
#:name 'player
#:hitboxes (list graze-hitbox kill-hitbox)
#:position (vec2 80.0 24.0)
#:bullet-field bullet-field
#:polarity 'white))
(define-method (on-boot (player <player>))
(attach-to player
(make <atlas-sprite>
#:name 'ship
#:atlas ship-atlas
#:index 0
#:origin (vec2 12.0 12.0))))
(define (shoot player ox)
(let ((speed 8.0)
(pos (position player))
(bullets (bullet-field player))
(y-offset 6.0))
(spawn-bullet bullets ikaruga-bullet (polarity player)
(+ (vec2-x pos) ox) (+ (vec2-y pos) y-offset)
0.0 speed)))
(define-method (update (player <player>) dt)
;; Adjust velocity to force player to stay within the bounds of the
;; screen.
(let ((p (position player))
(v (velocity player)))
(cond
((< (+ (vec2-x p) (vec2-x v)) 0.0)
(set-vec2-x! v (- (vec2-x p))))
((> (+ (vec2-x p) (vec2-x v)) 160.0)
(set-vec2-x! v (- 160.0 (vec2-x p)))))
(cond
((< (+ (vec2-y p) (vec2-y v)) 0.0)
(set-vec2-y! v (- (vec2-y p))))
((> (+ (vec2-y p) (vec2-y v)) 240.0)
(set-vec2-y! v (- 240.0 (vec2-y p))))))
;; Shooting logic
(when (shooting? player)
(let ((t (shoot-time player)))
;; Fire every n frames
(when (and (zero? (modulo t 2))
;; can't shoot while switching polarity.
(not (eq? (polarity player) 'none)))
;; The first shot is a single shot, everything after is double
;; fire. This enables players to just tap the fire button to
;; fire off precision shots.
(cond
;; single shot
((zero? t)
(shoot player 0.0))
;; double shot. give a buffer of 4 frames so players can
;; reliably fire just a single shot.
((> t 4)
(shoot player 5.0)
(shoot player -5.0))))
(set! (shoot-time player) (+ t 1))))
(next-method))
(define-method (steer (player <player>) up? down? left? right?)
(let ((v (velocity player)))
(set-vec2! v (+ (if left? -1.0 0.0) (if right? 1.0 0.0))
(+ (if up? 1.0 0.0) (if down? -1.0 0.0)))
(vec2-normalize! v)
(vec2-mult! v (speed player))))
(define-method (start-shooting (player <player>))
(set! (shooting? player) #t)
(set! (shoot-time player) 0))
(define-method (stop-shooting (player <player>))
(set! (shooting? player) #f))
(define-method (toggle-polarity (player <player>))
(let ((old (polarity player)))
;; If polarity is none it means we are already switching so ignore
;; the request.
(unless (eq? old 'none)
(run-script player
;; There's a brief moment when switching polarity where the
;; player is vulnerable to all bullets.
(set! (polarity player) 'none)
(sleep 7)
(set! (polarity player) (if (eq? old 'white) 'black 'white))
;; Change sprite
(set! (index (& player ship)) (if (eq? old 'white) 4 0))))))
(define-method (fire-homing-missiles (player <player>))
(let* ((e (energy player))
(n (quotient e 10)))
(set! (energy player) (- e (* n 10)))
;; TODO: search for nearest enemy and fire missiles
#t))
(define-method (increment-energy (player <player>))
(set! (energy player) (min (+ (energy player) 1) 120)))
(define-method (kill-maybe (player <player>))
(unless (invincible? player)
(set! (lives player) (- (lives player) 1))
;; Give player invincibility for a bit while they recover.
(run-script player
(set! (invincible? player) #t)
;; 3 seconds of blinking
(blink 18 5)
(set! (invincible? player) #f))))
(define-method (on-collision (player <player>) (other <actor>)
hitbox other-hitbox)
(when (eq? hitbox kill-hitbox)
(kill-maybe player)))
(define-method (on-collision (player <player>) bullet bullet-polarity hitbox)
(cond
;; Absorb bullets of the same polarity.
((and (eq? hitbox graze-hitbox)
(eq? bullet-polarity (polarity player)))
(increment-energy player)
#t)
;; If a bullet makes it to the kill hitbox, lose a life.
((eq? hitbox kill-hitbox)
(kill-maybe player)
#t)
(else #f)))
|
