Problem with the line color

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Kibita
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Posts: 31
Joined: Tue Dec 29, 2015 7:46 pm

Problem with the line color

Post by Kibita »

Hello!

I'm trying to make an effect that "simulates" the stars in movement and I'm making them with the color white, but some lines are showing grey, as you can see in the image:

Image

And here's where I draw each line:

Code: Select all

function GameEffect:draw()
    for i=1, #self.rays do
        love.graphics.setColor(255, 255, 255)
        love.graphics.setLineWidth(1.5)
        love.graphics.line(self.rays[i].x, self.rays[i].y, self.rays[i].x + self.rays[i].lenght, self.rays[i].y)
        love.graphics.setLineWidth(self.defaultWidth)
    end
end
I used setLineWidth to see if this could help, but it didn't.

What causes it and how can I fix it? Thank you.
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pgimeno
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Posts: 2614
Joined: Sun Oct 18, 2015 2:58 pm

Re: Problem with the line color

Post by pgimeno »

Can't reproduce:

Code: Select all

local GameEffect = {}

function love.load()
  love.window.setMode(430, 356)
  local gen = love.math.newRandomGenerator(4)
  GameEffect.rays = {}
  GameEffect.defaultWidth = 1
  for i = 1, 15 do
    GameEffect.rays[#GameEffect.rays + 1] = {
      lenght = 60;
      x = gen:random(370);
      y = gen:random(354);
    }
  end
end

function love.draw()
    love.graphics.clear(217, 207, 80)
    GameEffect:draw()
end

function GameEffect:draw()
    for i=1, #self.rays do
        love.graphics.setColor(255, 255, 255)
        love.graphics.setLineWidth(1.5)
        love.graphics.line(self.rays[i].x, self.rays[i].y, self.rays[i].x + self.rays[i].lenght, self.rays[i].y)
        love.graphics.setLineWidth(self.defaultWidth)
    end
end

function love.keypressed(k) if k == "escape" then love.event.quit() end end
Image

If you need further help, please post a .love file or at least a complete reproducible test case like the above.
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rmcode
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Location: Germany
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Re: Problem with the line color

Post by rmcode »

@Kibita: Is it possible you are drawing the lines at non-integer coordinates (10.393, 12.939 for example)? If so, try to math.floor the coordinates before drawing.
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pgimeno
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Re: Problem with the line color

Post by pgimeno »

Modifying the coordinate generation above as follows, I still can't reproduce:

Code: Select all

      x = gen:random()*370;
      y = gen:random()*354;
Image
(the differences are subtle, but visible when zooming)
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Kibita
Prole
Posts: 31
Joined: Tue Dec 29, 2015 7:46 pm

Re: Problem with the line color

Post by Kibita »

Oh my God, I just used love.graphics.clear that pgimeno used and it worked!
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Pangit
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Posts: 148
Joined: Thu Jun 16, 2016 9:20 am

Re: Problem with the line color

Post by Pangit »

This was what I got..
colour.png
colour.png (1.32 KiB) Viewed 1974 times
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slime
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Posts: 2932
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Location: Nova Scotia, Canada
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Re: Problem with the line color

Post by slime »

love.graphics.clear is unnecessary in the default [wiki]love.run[/wiki], since LÖVE calls it directly before love.draw is called. You can use [wiki]love.graphics.setBackgroundColor[/wiki] to set the color it uses for that clear call.
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pgimeno
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Posts: 2614
Joined: Sun Oct 18, 2015 2:58 pm

Re: Problem with the line color

Post by pgimeno »

Indeed, same result without love.graphics.clear as expected. For some reason I thought that setBackgroundColor had been removed.

Code: Select all

local GameEffect = {}

function love.load()
  love.window.setMode(430, 356)
  local gen = love.math.newRandomGenerator(4)
  GameEffect.rays = {}
  GameEffect.defaultWidth = 1
  for i = 1, 15 do
    GameEffect.rays[#GameEffect.rays + 1] = {
      lenght = 60;
      x = gen:random()*370;
      y = gen:random()*354;
    }
  end
  love.graphics.setBackgroundColor(217, 207, 80)
end

function love.draw()
    GameEffect:draw()
end

function GameEffect:draw()
    for i=1, #self.rays do
        love.graphics.setColor(255, 255, 255)
        love.graphics.setLineWidth(1.5)
        love.graphics.line(self.rays[i].x, self.rays[i].y, self.rays[i].x + self.rays[i].lenght, self.rays[i].y)
        love.graphics.setLineWidth(self.defaultWidth)
    end
end

function love.keypressed(k) if k == "escape" then love.event.quit() end end
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