Image scaling problem? (FULLSCREEN)

By Gammel Date 2016-02-19 18:24

Maybe i'm doing something wrong, but after drawing a 8x8 image all over the screen (tile layer) scaled by 4x (32x32), a black line appears at the top of the screen.

This only happens in fullscreen with a 8x8 scaled image with :retro=>true.
Also, if :retro is false all the screen looks like a grid (nice way to make a map editor :P)

Here's the code: (I'm using a 8x8 blue square as the image to tile).

require 'gosu'

class Window < Gosu::Window
  
  
  def draw()
    (Gosu::available_width/32).to_i.times do |x|
      (Gosu::available_height/32).to_i.times do |y|
        @img.draw( x*32, y*32, 1, 4, 4)
      end
    end
  end
  
  def update()
    
  end
  
  def initialize()
    super Gosu::available_width, Gosu::available_height, true
    
    @img = Gosu::Image.new("img.png", {:retro=>true})
  end
  
end

win = Window.new()
win.show

By jlnr (dev) Date 2016-02-20 00:27

Gosu::available_height returns the height available for running games in *windowed* mode, so if you are on Windows, this will be the same as Gosu::screen_height minus space for the start menu/task bar at the bottom.
You should be seeing a black bar at the top and bottom each, and you are probably looking for Gosu::screen_width and Gosu::screen_height instead.

And if you want to stretch images without :retro => true and without producing a grid effect, :tileable => true was designed exactly for that purpose :) Hope that helps!

By Gammel Date 2016-02-20 02:04

:tileable seems to have solved the problem with resizing, however, after changing available_height with screen_height the bottom black bar dissapeared, but the top black bar is still there. Is that supposed to happen?

require 'gosu'

class Window < Gosu::Window
  
  
  def draw()

    ((Gosu::screen_width/32)+1).times do |x|
      ((Gosu::screen_height/32)+1).times do |y|
        @img.draw( (x*32), (y*32),0,4,4)
      end
    end
    
    Gosu::draw_rect(0,0,Gosu::screen_width, 32, Gosu::Color::WHITE)
  end
  
  def update()
    
  end
  
  def initialize()
    super Gosu::screen_width, Gosu::screen_height, true
    
    @img = Gosu::Image.new("img.png", {:retro=>true, :tileable=>true})
  end
  
end

win = Window.new()
win.show

By nietzschette Date 2016-02-20 09:24

try replacing line 10 in your draw function with this

@img.draw( (x*32), (y*32),1,4,4)

let us know if that fixes it.

By jlnr (dev) Date 2016-02-20 10:36

Nope. Can you please post a screenshot? Which operating system and which version of Gosu are you using?

By Gammel Date 2016-02-20 17:04

Not only do i get a black bar at the top, but also the white rect that takes screen_width doesn't reach it's full size (ends like 20 pixels before the screen width)

..
I can't seem to find a way to take a screenshot (as this only happens in fullscreen), but it looks like this:

(Modifying the z value didn't change anything)

(Windows 7 - 32 bits, Gosu 0.10.5)

By jlnr (dev) Date 2016-02-20 23:51

That's really curious. I wonder if it has anything to do with your DPI settings? Are you running Windows 7 at 100%, 125% or 150% font scale? (It's somewhere in the display settings.)

I'll give it a try on my Windows 7 VM ASAP.

By Gammel Date 2016-02-20 23:56

100%.