# SOME DESCRIPTIVE TITLE # Copyright (C) YEAR Free Software Foundation, Inc. # This file is distributed under the same license as the PACKAGE package. # FIRST AUTHOR , YEAR. # # msgid "" msgstr "" "Project-Id-Version: PACKAGE VERSION\n" "POT-Creation-Date: 2013-11-11 09:56+0100\n" "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n" "Last-Translator: FULL NAME \n" "Language-Team: LANGUAGE \n" "Language: \n" "MIME-Version: 1.0\n" "Content-Type: text/plain; charset=UTF-8\n" "Content-Transfer-Encoding: 8bit\n" #. type: One-char language identifier #: train401.languagecode:1 #, no-wrap msgid "E" msgstr "R" #. type: ScriptName-text #: train401/scene.txt:1 train401/scene.txt:3 #, no-wrap msgid "train401:Dragster" msgstr "train401:Миноискатель" #. type: Resume-text #: train401/scene.txt:2 #, no-wrap msgid "train401:Program a progressive deceleration in order to avoid the mines right behind the goal." msgstr "train401:Запрограммируйте постепенное снижение скорости, чтобы избежать мины прямо перед целью." #. type: \b; header #: train401-help/tdragst.txt:1 #, no-wrap msgid "Exercise" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:3 #, no-wrap msgid "Reach the finishing pad (25m in front of you) as fast as possible, using the instruction motor( , ). You will have to slow down progressively at the end of the move, otherwise the bot will get blown up on the mines." msgstr "" #. type: Plain text #: train401-help/tdragst.txt:5 #, no-wrap msgid "You could very well write no more than move(25);, this would work perfectly well. However, the aim of this exercise is to learn how to use the instruction motor." msgstr "" #. type: Plain text #: train401-help/tdragst.txt:7 #, no-wrap msgid "This instruction asks for two values:\n" msgstr "" #. type: Bullet: '1)' #: train401-help/tdragst.txt:7 #, no-wrap msgid "The speed of the left-hand motor." msgstr "" #. type: Bullet: '2)' #: train401-help/tdragst.txt:8 #, no-wrap msgid "The speed of the right-hand motor." msgstr "" #. type: \s; block (usually verbatim code) #: train401-help/tdragst.txt:11 #, no-wrap msgid "\tmotor( left, right );" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:13 #, no-wrap msgid "The values must range between -1 and 1:\n" msgstr "" #. type: Bullet: '-' #: train401-help/tdragst.txt:13 #, no-wrap msgid "1 = full throttle backward" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:16 #, no-wrap msgid "" " 0 = stop\n" " 1 = full throttle forward" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:18 #, no-wrap msgid "For example, motor(0.5, 0.5); will move the motor forward with half-speed, until new instructions are given to the motors." msgstr "" #. type: Plain text #: train401-help/tdragst.txt:20 #, no-wrap msgid "With the instruction motor(0.5, 0.6);, the bot will move forward with half-speed, turning at the same time slightly to the left: the right-hand motor moves a little faster (0.6) than the left-hand motor (0.5)." msgstr "" #. type: \b; header #: train401-help/tdragst.txt:21 #, no-wrap msgid "General principle" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:24 #, no-wrap msgid "" "In order to move forward for exactly 25 meters and not more, you must move full speed during the first 23 meters, then reduce the speed of the motors progressively during the last two meters.\n" "The variable position gives you at any moment the current position of the bot, and the instruction distance( , ); returns the distance between two points. The best way to know where you are consists in saving the current position before the start into a variable, for example a variable called start. Then you can calculate the distance between the starting position and your current position with distance(position, start)." msgstr "" #. type: \b; header #: train401-help/tdragst.txt:25 #, no-wrap msgid "The program" msgstr "" #. type: Bullet: '1)' #: train401-help/tdragst.txt:26 #, no-wrap msgid "declare the variables" msgstr "" #. type: \s; block (usually verbatim code) #: train401-help/tdragst.txt:29 #, no-wrap msgid "" "\tpoint start;\n" "\tfloat len;" msgstr "" #. type: Bullet: '2)' #: train401-help/tdragst.txt:30 #, no-wrap msgid "save the starting position" msgstr "" #. type: \s; block (usually verbatim code) #: train401-help/tdragst.txt:32 #, no-wrap msgid "\tstart = position;" msgstr "" #. type: Bullet: '3)' #: train401-help/tdragst.txt:33 #, no-wrap msgid "start full throttle :" msgstr "" #. type: \s; block (usually verbatim code) #: train401-help/tdragst.txt:35 #, no-wrap msgid "\tmotor(1, 1);" msgstr "" #. type: Bullet: '4)' #: train401-help/tdragst.txt:36 #, no-wrap msgid "Perform an infinite while loop:" msgstr "" #. type: \s; block (usually verbatim code) #: train401-help/tdragst.txt:45 #, no-wrap msgid "" "\twhile ( true )\n" "\t{\n" "\t\tlen = distance(position, start);\n" "\t\tif ( len > 25-2 )\n" "\t\t{\n" "\t\t\tmotor( less than before ! );\n" "\t\t}\n" "\t}" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:47 #, no-wrap msgid "As long as the distance between the start and the current position is smaller than 23m, the instruction in braces after the if instruction will not be executed, so the motors keep their maximum speed as they were told by the motor(1,1); instruction." msgstr "" #. type: Plain text #: train401-help/tdragst.txt:49 #, no-wrap msgid "In order to slow down progressively, the speed of the motors must be proportional to the remaining distance:\n" msgstr "" #. type: Bullet: 'o' #: train401-help/tdragst.txt:49 #, no-wrap msgid "2.0 meters left -> speed = 1.00 (maximum)" msgstr "" #. type: Bullet: 'o' #: train401-help/tdragst.txt:50 #, no-wrap msgid "1.5 meters left -> speed = 0.75" msgstr "" #. type: Bullet: 'o' #: train401-help/tdragst.txt:51 #, no-wrap msgid "1.0 meter left -> speed = 0.50" msgstr "" #. type: Bullet: 'o' #: train401-help/tdragst.txt:52 #, no-wrap msgid "0.5 meter left -> speed = 0.25" msgstr "" #. type: Bullet: 'o' #: train401-help/tdragst.txt:53 #, no-wrap msgid "0.0 meter left -> speed = 0.00 (stop)" msgstr "" #. type: Image filename #: train401-help/tdragst.txt:55 #, no-wrap msgid "tdragst1" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:57 #, no-wrap msgid "You can use the following expression (25-len)/2 in order to calculate the value for the speed instruction that must be given to the motors." msgstr "" #. type: Plain text #: train401-help/tdragst.txt:59 #, no-wrap msgid "It is now up to you to put everything together and to test the program." msgstr "" #. type: \b; header #: train401-help/tdragst.txt:60 #, no-wrap msgid "Remark" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:62 #, no-wrap msgid "You can use values greater than 1 for the instruction motor();, but the bot will not move any faster." msgstr "" #. type: \t; header #: train401-help/tdragst.txt:63 #, no-wrap msgid "See also" msgstr "" #. type: Plain text #: train401-help/tdragst.txt:64 #, no-wrap msgid "Programming, types and categories." msgstr ""