How do you update and change an object in ruby 2D? - ruby

I have a text object in ruby 2D showing score. How do I update the text?
I have this so far
update do
text = Text.new("Score: #{#score}")
end
Instead of replacing it, it is creating a new text object on top of it. How could you replace it instead of adding it on?

Based on docs it seems like you need to instantiate the Text object outside of the update loop. This will draw it to the screen "forever" until you call the remove method.
In your current code you are just instantiating a new object every time, and Ruby 2D is secretly keeping it around even though you don't have it assigned to a variable.
Unlike some other 2D libraries like Gosu, Ruby 2D does not stop drawing something until you explicitly tell it to.
Try
#text = Text.new("Score: #{#score}")
update do
...
#text.remove # At a time you want to stop displaying that text.
...
end
Adding and removing objects in Ruby 2D

here a simple example how to use the Text class in ruby2d
require 'ruby2d'
sector = 3
txt = Text.new(
sector.to_s,
x: 10, y: 10,
size: 20,
color: 'white',
z: 10
)
on :key_down do |event|
case event.key
when 'a'
sector += 1
txt.text = sector.to_s
when 's'
sector -= 1
txt.text = sector.to_s
end
end
show

Related

How do I make a script affect all its children in Roblox LUA?

I'm new to programming in LUA, although I've learned similar languages like JS. It's frustrating if I have to alter the same script in many parts in a group by replacing each script, and I don't know of an elegant way to do it. Instead, I decided to nest all the parts inside of the script. I've seen some examples and I've tried to adapt some of them, but they don't exactly apply to what I want to do and I can't get them to work.
In essence, what I'm trying to do is monitor all the bricks for a player to contact them. I took the original disappearing brick script that was nested inside each brick and modified it. If a part (brick) is touched, that should call the onTouch function, which will make the brick's transparency decrease over time until the in pairs loop is done, after which the brick disappears and CanCollide is turned off. After 2 seconds, it then returns back to normal. I think the problem is with the coding I used to monitor the parts as I don't really understand the right way to monitor multiple objects. Can someone please help? Thanks!
File structure:
function onTouched(brick)
local delay = .1 -- the delay between each increase in transparency (affects speed of disappearance)
local RestoreDelay = 2 -- delay before the brick reappears
local inc = .1 -- how much the brick disappears each time
-- All characters have a Humanoid object
-- if the model has one, it is a character
local h = script.Child:findFirstChild("Humanoid") -- Find Humanoids in whatever touched this
if (h ~=nil) then -- If there is a Humanoid then
h.Health = h.MaxHealth -- Set the health to maximum (full healing)
for x=0,1, inc do
script.Child.Transparency = x+inc
script.Child.CanCollide = true
wait(delay)
end
wait(delay)
script.Child.Transparency = 1
script.Child.CanCollide = false
wait(RestoreDelay)
script.Child.Transparency = 0
script.Child.CanCollide = true
else
end
end
while true do
local bricks=script:GetChildren():IsA("basic.part")
for x=1,brick in pairs(bricks) do
brick.Touched:connect(onTouched(brick)) -- Make it call onTouched when touched
end
end
end
For the most part, you've gotten it right, but you've got a few syntax errors where there are different conventions between JavaScript and Lua.
In JS, you would fetch an array of objects and then bee able to filter it immediately, but in Lua, there is limited support for that. So a JavaScript line like :
var bricks = script.GetChildren().filter(function(item) {
return item === "basic.part"
})
cannot be done all in one line in Lua without assistance from some library. So you'll need to move the check into the loop as you iterate over the objects.
Other than that, the only other thing to change is the onTouched handler's function signature. The BasePart.Touched event tells you which object has touched the brick, not the brick itself. But by creating a higher order function, it's easy to get access to the brick, and the thing that touched it.
-- create a helper function to access the brick and the thing that touched it
function createOnTouched(brick)
-- keep track whether the animation is running
local isFading = false
return function(otherPart)
-- do not do the animation again if it has already started
if isFading then
return
end
local delay = .1 -- the delay between each increase in transparency (affects speed of disappearance)
local restoreDelay = 2 -- delay before the brick reappears
local inc = .1 -- how much the brick disappears each time
-- All characters have a Humanoid object, check for one
local h = otherPart.Parent:FindFirstChild("Humanoid")
if h then
-- heal the player
h.Health = h.MaxHealth
-- start fading the brick
isFading = true
brick.CanCollide = true
for i = 0, 1, inc do
brick.Transparency = i
wait(delay)
end
-- turn off collision for the brick
wait(delay)
brick.Transparency = 1
brick.Anchored = true
brick.CanCollide = false
-- turn the part back on
wait(restoreDelay)
brick.Transparency = 0
brick.CanCollide = true
-- reset the animation flag
isFading = false
end
end
end
-- loop over the children and connect touch events
local bricks = script:GetChildren()
for i, brick in ipairs(bricks) do
if brick:IsA("BasePart") then
local onTouchedFunc = createOnTouched(brick)
brick.Touched:Connect(onTouchedFunc)
end
end

How can i change the character image non Ruby Gosu

im building a basic game in the style of the original pokemon games using the ruby gosu library. Ive managed to figure out how to move the originally loaded sprite about but i cant figure out how to clear that sprite and draw the new sprite e.g. back view in its place.
Ive been looking throught the documentation and came across the "insert" method, although im not sure if this is what i want. Any help?
im creating the var in the initialize method then drawing it later on like so:
def initialize
#character_image = Gosu::Image.new("media/images/char.png", :tileable => false)
end
def draw
#character_image.draw(#character_location_X, #character_location_Y, 1)
end
You need to make a class for your character, which needs an update and draw function. In the update function, when input such as WASD is received you can switch the image of the sprite. If you don't have a sprite sheet, you'll have to load multiple images and switch between them.
Here's some ruby pseudocode to help you:
#back_image = Gosu::Image.new("media/images/back.png")
#front_image = Gosu::Image.new("media/images/front.png")
#left_image = Gosu::Image.new("media/images/left.png")
#right_image = Gosu::Image.new("media/images/right.png")
current_image = front_image
This goes in your update function:
if up
current_image = back_image
elsif down
current_image = front_image
elsif right
current_image = right_image
elsif left
current_image = left_image
end
Then in your draw function all you need to do is
def draw
#current_image.draw(#character_location_X, #character_location_Y, 1)
end
This is a pretty basic way, but if you use a sprite sheet, you can create your own animation class that Gosu can use that allows you to select between certain ranges of frames of your character spritesheet.

How to move an image in Lua?

I am new to Lua programming and I am having problems while trying to move an image from a set of coordinates to another.
What I am trying to create is to be used with the X-Plane flight simulator. There is a library called SASL (www.1-sim.com), that was created to make plugins (for X-Plane) creation easir, since the default language is C++ and many people find it difficult.
In general, SASL works as a bridge between Lua and X-Plane, in general lines, the scripts you write reads some data straight from X-Plane (DataRefs) while it is running and depending on the code you wrote its execute commands or many other things that it is possible.
So, when using SASL to create cockpit/panel gauges it uses a base file, named 'avionics.lua' that works as a class and loads all gauges you create for the specific aircraft you are working on. For example my avionics.lua file looks like this:
size = { 2048, 2048 }
components = {
flaps {};
};
where, 'size' is the size that will be used for things to be drawn and components is an array of gauges, in this case the flaps gauge.
The rest of the work is to create the gauge functionality and this is done in a separate file, in my case, called 'flaps.lua'.
Within flaps.lua, is where I need to code the flaps indicator functionality which is to load 2 images: one for the back ground and the second one for the flaps indicator.
The first image is a fixed image. The second one will move throught the 'y' axis based on the flaps indicator DataRef (flapsDegree property below).
The code below when X-Plane is running displays the background image and the flaps indicator on its first stage which is 0 as you can see on the image.
size = {78,100}
local flapsDegree = globalPropertyf("sim/cockpit2/controls/flap_ratio")
local background = loadImage("gfx/Flaps.png")
local indicator = loadImage("gfx/Flaps_Indicator.png")
local flaps = get(flapsPosition)
components = {
texture { position = {945, 1011, 60, 100}, image = background},
texture { position = {959, 1097, 30, 9}, image = indicator},
}
Image
Now, the problem comes when I need to implement the logic for moving the 'indicator' image through the 'y' axis.
I have tried this code without success:
if flaps == 0.333 then
indicator.position = {959, 1075, 30, 9}
end
So how could I accomplish that?
I am not familiar with the SALS library. I just had a quick look into it.
Everything you need to know is in the manuals on the website you linked.
In particular http://www.1-sim.com/files/SASL300.pdf
Everytime your screen is updated each components draw() function will be called.
So if you want to change something dynamically you have to put that into the component's draw function.
If you open the SALS sources you'll find basic components which show you how to use that stuff. One of them is needle.lua:
-- default angle
defineProperty("angle", 0)
-- no image
defineProperty("image")
function draw(self)
local w, h = getTextureSize(get(image))
local max = w
if h > max then
max = h
end
local rw = (w / max) * 100
local rh = (h / max) * 100
drawRotatedTexture(get(image), get(angle),
(100 - rw) / 2, (100 - rh) / 2, rw, rh)
end
If you check the manual you'll find that there is not only a drawRotatedTexture function but many other functions for drawing stuff. Just play around. Try drawTexture for your purpose.
If you don't know what you have to program, open every single lua file in the library and read it together with the Lua reference manual and the SALS documentation until you understand what is going on. Once you understand the existing code you can extend it with ease.

scrollable window ncurses ruby

I created a class that I am trying to make to simulate richtextbox, sort of, on windows forms. this means when you add new data to the form/richtextbox it is added to the bottom of the box/window and the rest is scrolled up one line.
ive tried to enable scrollok(), but it does not seem to want to scroll. i am not sure if it's bugged or my way of implementing it is wrong.
class Textpad
attr_accessor :data, :name, :window
def initialize(name, height, width, startx, starty)
#data = []
#name = name
#height = height
#width = width
#startx = startx
#starty = starty
Ncurses.refresh
#window = Ncurses.newwin(height, width, starty, startx)
#window.scrollok true
#window.wrefresh
end
def add(packetid, username, message)
#data.push [Time.new.strftime('[%T]'), packetid, username, message]
#data.shift if #data.length > 500
end
def draw
Ncurses.init_pair(1, Ncurses::COLOR_YELLOW, Ncurses::COLOR_BLACK)
Ncurses.init_pair(2, Ncurses::COLOR_CYAN, Ncurses::COLOR_BLACK)
Ncurses.init_pair(3, Ncurses::COLOR_RED, Ncurses::COLOR_BLACK)
Ncurses.init_pair(4, Ncurses::COLOR_WHITE, Ncurses::COLOR_BLACK)
#window.wclear
position = 0
#data.each do |timestamp, packetid, username, message|
case packetid
when '1005'
#window.mvwprintw(1*position, 1, "#{timestamp} «#{username}» #{message}")
#window.mvchgat(1*position, timestamp.length+2, 1, Ncurses::A_NORMAL, 3, NIL)
#window.mvchgat(1*position, timestamp.length+3+username.length, 1, Ncurses::A_NORMAL, 3, NIL) #colorize the symboles around the username
end
position += 1
end
#window.wrefresh
end
end
the problem would be inside my draw method of the Textpad class. i can fill the data array for the Textpad class with hundreds of entries but only the very top of the array gets written (until it reaches the bottom of the window) with no scrolling. Do i manually have to scroll the screen or something? from the documentation it says it should automatically scroll when the cursor reaches the bottom and another line is added.
To quote the man page:
The scrollok option controls what happens when the cursor of a window is moved off the edge of the window or scrolling region, either as a result of a newline action on the bottom line, or typing the last character of the last line. If disabled, (bf is FALSE), the cursor is left on the bottom line. If enabled, (bf is TRUE), the window is scrolled up one line...
What is happening in your code is that you are attempting to print outside the window which is an error, but an error that curses handles by not printing anything.
You can either print an new line when you get to the bottom of the window or once your reach the bottom of the window you can call #window.scroll.
Either way you will need to keep printing on the last line if you are explicitly setting the position.

How to position editbox's cursor in shoes?

Shoes is very handy GUI tool. I would like to do a search form so that a user is helped to navigate through larger texts for editing. For this I need to move the cursor within an editbox element.
Here you'll see my question in code:
Shoes.app do
stack do
p=para "After pressing 'search' a question will arise"
box=edit_box
box.text="One\nof\nthe\nmost\nstriking\ndifferences\nbetween\na\ncat\nand\na\nlie\nis\nthat\na\ncat\nhas\nonly\nnine lives."
flow :margin_top=>0.1 do
search=edit_line
button("search") do
pos=box.text.index search.text
y = box.text[0..pos].split.size-1 if pos
if not y.nil?
#For example if you searched "only" then
#cursor should jump/scroll to line 17.
#
#Anything there for cursor positioning,
#like: box.cursor=[0,y]
#
p.text="How can I move editbox's cursor in line #{y+1}?"
else
alert "'#{search.text}' not found"
end
end
end
end
end
Is there is any way to change cursor's position of an editbox? If not, do you know an alternative way of implementation?
Unfortunately, Shoes doesn't seem to provide any way to do that. These are the only methods defined on EditBox (it inherits from Native, which has several methods, but again, none to reposition the cursor).
rb_define_method(cEditBox, "text", CASTHOOK(shoes_edit_box_get_text), 0);
rb_define_method(cEditBox, "text=", CASTHOOK(shoes_edit_box_set_text), 1);
rb_define_method(cEditBox, "draw", CASTHOOK(shoes_edit_box_draw), 2);
rb_define_method(cEditBox, "change", CASTHOOK(shoes_control_change), -1);
http://github.com/why/shoes/blob/cea39a8bf9a5b7057b1824a9fab868d1f8609d69/shoes/ruby.c

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