* bug#20579: 24.4; Pong bat loses 1/3rd of its length if the ball hits it too quickly
@ 2015-05-14 18:58 Matt Lee
2019-08-07 15:03 ` Mauro Aranda
0 siblings, 1 reply; 3+ messages in thread
From: Matt Lee @ 2015-05-14 18:58 UTC (permalink / raw)
To: 20579
* Start Emacs and start pong
* Immediately move the left bat down a square or two
* As the ball is about to miss your bat, move up quickly so your bat
essentially overrwrites the space of the ball on screen
* The ball bounces, but your bat is left as two, not three squares long.
In GNU Emacs 24.4.1 (x86_64-pc-linux-gnu, GTK+ Version 3.14.5)
of 2015-03-07 on trouble, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11604000
System Description: Debian GNU/Linux 8.0 (jessie)
Configured using:
`configure --build x86_64-linux-gnu --prefix=/usr
--sharedstatedir=/var/lib --libexecdir=/usr/lib
--localstatedir=/var/lib --infodir=/usr/share/info
--mandir=/usr/share/man --with-pop=yes
--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.4/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.4/site-lisp:/usr/share/emacs/site-lisp
--build x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib
--libexecdir=/usr/lib --localstatedir=/var/lib
--infodir=/usr/share/info --mandir=/usr/share/man --with-pop=yes
--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.4/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.4/site-lisp:/usr/share/emacs/site-lisp
--with-x=yes --with-x-toolkit=gtk3 --with-toolkit-scroll-bars
'CFLAGS=-g -O2 -fstack-protector-strong -Wformat
-Werror=format-security -Wall' CPPFLAGS=-D_FORTIFY_SOURCE=2
LDFLAGS=-Wl,-z,relro'
Important settings:
value of $LANG: en_US.UTF-8
locale-coding-system: utf-8-unix
Major mode: Info
Minor modes in effect:
tooltip-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
tool-bar-mode: t
menu-bar-mode: t
file-name-shadow-mode: t
global-font-lock-mode: t
font-lock-mode: t
blink-cursor-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
buffer-read-only: t
line-number-mode: t
transient-mark-mode: t
Recent input:
M-x p o n g <return> <left> <right> <left> <left> <left>
<left> <left> <right> <right> <right> <right> <right>
<right> <right> <help-echo> <right> <left> <left> <left>
<up> <up> <down> <down> <down> <down> <down> <down>
<up> <left> <right> <down> <up> <up> <left> <left>
<left> <left> <left> <left> <left> <left> <left> <left>
<left> <left> <right> <right> <up> <up> <up> <up> <up>
<up> <down> <up> <up> <up> <down> <down> <down> <down>
<down> <up> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <left> <left> <left>
<left> <left> <left> <left> <right> <left> <down> <right>
<right> <left> <down> <up> <up> <down> <left> <right>
<right> <left> <down> <down> <down> <down> <down> <down>
<down> <down> <right> <right> <right> <right> <right>
<right> <right> <right> <right> <right> <right> <left>
<right> <left> <right> <left> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<menu-bar> <help-menu> <emacs-manual-bug> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <menu-bar> <help-menu> <send-emacs-bug
-report>
Recent messages:
call-interactively: Buffer is read-only: #<buffer *Pong*> [5 times]
Quit
call-interactively: Buffer is read-only: #<buffer *Pong*>
command-execute: Buffer is read-only: #<buffer *Pong*>
ESC ESC <menu-bar> is undefined
<tools> is undefined
<games> is undefined
<pong> is undefined
Error running timer `kill-buffer': (error "No buffer named *Pong*")
Composing main Info directory...done
user-error: Info file emacs does not exist
Load-path shadows:
/usr/share/emacs/24.4/site-lisp/debian-startup hides
/usr/share/emacs/site-lisp/debian-startup
/usr/share/emacs24/site-lisp/cmake-data/cmake-mode hides
/usr/share/emacs/site-lisp/cmake-mode
/usr/share/emacs24/site-lisp/dictionaries-common/ispell hides
/usr/share/emacs/24.4/lisp/textmodes/ispell
/usr/share/emacs24/site-lisp/dictionaries-common/flyspell hides
/usr/share/emacs/24.4/lisp/textmodes/flyspell
Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
help-fns mail-prsvr mail-utils info easymenu disp-table pong gamegrid
markdown-mode-autoloads multiple-cursors-autoloads php-mode-autoloads
web-mode-autoloads zenburn-theme-autoloads package epg-config time-date
tooltip electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
x-win x-dnd tool-bar dnd fontset image regexp-opt fringe tabulated-list
newcomment lisp-mode prog-mode register page menu-bar rfn-eshadow timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
frame cham georgian utf-8-lang misc-lang vietnamese tibetan thai
tai-viet lao korean japanese hebrew greek romanian slovak czech european
ethiopic indian cyrillic chinese case-table epa-hook jka-cmpr-hook help
simple abbrev minibuffer nadvice loaddefs button faces cus-face macroexp
files text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
dbusbind gfilenotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty emacs)
Memory information:
((conses 16 118206 6010)
(symbols 48 20574 0)
(miscs 40 88 185)
(strings 32 21586 4423)
(string-bytes 1 540426)
(vectors 16 12016)
(vector-slots 8 418703 5823)
(floats 8 80 419)
(intervals 56 3093 0)
(buffers 960 14)
(heap 1024 52752 1029))
--
Matt Lee
Technical Lead, Creative Commons, Boston, MA
https://keybase.io/mattl
"Creativity can be a social contribution, but only in
so far as society is free to use the results." -- Stallman
^ permalink raw reply [flat|nested] 3+ messages in thread
* bug#20579: 24.4; Pong bat loses 1/3rd of its length if the ball hits it too quickly
2015-05-14 18:58 bug#20579: 24.4; Pong bat loses 1/3rd of its length if the ball hits it too quickly Matt Lee
@ 2019-08-07 15:03 ` Mauro Aranda
2019-08-10 8:52 ` Eli Zaretskii
0 siblings, 1 reply; 3+ messages in thread
From: Mauro Aranda @ 2019-08-07 15:03 UTC (permalink / raw)
To: 20579
[-- Attachment #1.1: Type: text/plain, Size: 234 bytes --]
tags 20579 patch
quit
Hello.
I can reproduce this bug in Emacs 25.3, Emacs 26.2 and the current
master.
I attach a patch that fixes this bug, and also does some improvement in
the collision detection of pong.
Best regards,
Mauro.
[-- Attachment #1.2: Type: text/html, Size: 296 bytes --]
[-- Attachment #2: 0001-Fix-pong-collision-detection.patch --]
[-- Type: text/x-patch, Size: 4119 bytes --]
From d1b442f4371193b03af4c6e05119d87fc8512f31 Mon Sep 17 00:00:00 2001
From: Mauro Aranda <maurooaranda@gmail.com>
Date: Tue, 6 Aug 2019 21:48:41 -0300
Subject: [PATCH] Fix pong collision detection
* lisp/play/pong.el (pong-update-game): If the ball hit the bat where
bats are positioned, draw again the bat cell in the old ball
position. (Bug#20579).
Also, avoid changing the direction of the ball right after hitting the
bats, and improve the collision detection against the borders.
---
lisp/play/pong.el | 83 ++++++++++++++++++++++++++++++++-----------------------
1 file changed, 49 insertions(+), 34 deletions(-)
diff --git a/lisp/play/pong.el b/lisp/play/pong.el
index 555c193..759dbb4 100644
--- a/lisp/play/pong.el
+++ b/lisp/play/pong.el
@@ -349,46 +349,61 @@ pong-update-game
(let ((old-x pong-x)
(old-y pong-y))
-
+ ;; Erase the last ball position.
+ (when (and (> old-y 0)
+ (< old-y (- pong-height 1)))
+ ;; If the ball hit the bat in the column where bats are positioned,
+ ;; and therefore changed its x direction, draw again the bat cell.
+ (if (or (and (= old-x 2) (< 0 pong-xx))
+ (and (= old-x (- pong-width 3)) (> 0 pong-xx)))
+ (gamegrid-set-cell old-x old-y pong-bat)
+ (gamegrid-set-cell old-x old-y pong-blank)))
+
+ ;; Update the ball position.
(setq pong-x (+ pong-x pong-xx))
- (setq pong-y (+ pong-y pong-yy))
-
- (if (and (> old-y 0)
- (< old-y (- pong-height 1)))
- (gamegrid-set-cell old-x old-y pong-blank))
-
+ ;; If the ball would go out of bounds, put it against the border.
+ (cond
+ ((<= (+ pong-y pong-yy) 0)
+ (setq pong-yy (- pong-yy))
+ (setq pong-y 1))
+ ((>= (+ pong-y pong-yy) (- pong-height 1))
+ (setq pong-yy (- pong-yy))
+ (setq pong-y (- pong-height 2)))
+ (t
+ (setq pong-y (+ pong-y pong-yy))
+ ;; Check if the ball is against the border now,
+ ;; and change the y direction if it is.
+ (when (or (<= pong-y 1) (>= pong-y (- pong-height 2)))
+ (setq pong-yy (- pong-yy)))))
+
+ ;; Draw the ball in its new position.
(if (and (> pong-y 0)
(< pong-y (- pong-height 1)))
(gamegrid-set-cell pong-x pong-y pong-ball))
+ ;; Hit bat, score a goal, or nothing.
(cond
- ((or (= pong-x 3) (= pong-x 2))
- (if (and (>= pong-y pong-bat-player1)
- (< pong-y (+ pong-bat-player1 pong-bat-width)))
- (and
- (setq pong-yy (+ pong-yy
- (cond
- ((= pong-y pong-bat-player1) -1)
- ((= pong-y (1+ pong-bat-player1)) 0)
- (t 1))))
- (setq pong-xx (- pong-xx)))))
-
- ((or (= pong-x (- pong-width 4)) (= pong-x (- pong-width 3)))
- (if (and (>= pong-y pong-bat-player2)
- (< pong-y (+ pong-bat-player2 pong-bat-width)))
- (and
- (setq pong-yy (+ pong-yy
- (cond
- ((= pong-y pong-bat-player2) -1)
- ((= pong-y (1+ pong-bat-player2)) 0)
- (t 1))))
- (setq pong-xx (- pong-xx)))))
-
- ((<= pong-y 1)
- (setq pong-yy (- pong-yy)))
-
- ((>= pong-y (- pong-height 2))
- (setq pong-yy (- pong-yy)))
+ ((and (or (= pong-x 3) (= pong-x 2))
+ (> 0 pong-xx) ; Collide with the bat if headed towards it.
+ (>= pong-y pong-bat-player1)
+ (< pong-y (+ pong-bat-player1 pong-bat-width)))
+ (setq pong-yy (+ pong-yy
+ (cond
+ ((= pong-y pong-bat-player1) -1)
+ ((= pong-y (1+ pong-bat-player1)) 0)
+ (t 1))))
+ (setq pong-xx (- pong-xx)))
+
+ ((and (or (= pong-x (- pong-width 4)) (= pong-x (- pong-width 3)))
+ (< 0 pong-xx) ; Collide with the bat if headed towards it.
+ (>= pong-y pong-bat-player2)
+ (< pong-y (+ pong-bat-player2 pong-bat-width)))
+ (setq pong-yy (+ pong-yy
+ (cond
+ ((= pong-y pong-bat-player2) -1)
+ ((= pong-y (1+ pong-bat-player2)) 0)
+ (t 1))))
+ (setq pong-xx (- pong-xx)))
((< pong-x 1)
(setq pong-score-player2 (1+ pong-score-player2))
--
2.7.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* bug#20579: 24.4; Pong bat loses 1/3rd of its length if the ball hits it too quickly
2019-08-07 15:03 ` Mauro Aranda
@ 2019-08-10 8:52 ` Eli Zaretskii
0 siblings, 0 replies; 3+ messages in thread
From: Eli Zaretskii @ 2019-08-10 8:52 UTC (permalink / raw)
To: Mauro Aranda; +Cc: 20579-done
> From: Mauro Aranda <maurooaranda@gmail.com>
> Date: Wed, 7 Aug 2019 12:03:49 -0300
>
> I can reproduce this bug in Emacs 25.3, Emacs 26.2 and the current
> master.
>
> I attach a patch that fixes this bug, and also does some improvement in
> the collision detection of pong.
Thanks, pushed to the master branch.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-08-10 8:52 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2015-05-14 18:58 bug#20579: 24.4; Pong bat loses 1/3rd of its length if the ball hits it too quickly Matt Lee
2019-08-07 15:03 ` Mauro Aranda
2019-08-10 8:52 ` Eli Zaretskii
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