Views
Gradients
gradient
Synopsis
gradient {color1, color2, color3, ..., direction = 'horizontal' or 'vertical'}
Creates a gradient object (really just an image) from a table of colors to be evenly spaced throughout the gradient, in the direction specified by the "direction" key of the parameter table.
Source
function gradient(colors)
local direction = colors.direction or "horizontal"
if direction == "horizontal" then
direction = true
elseif direction == "vertical" then
direction = false
else
error("Invalid direction '" .. tostring(direction) "' for gradient. Horizontal or vertical expected.")
end
local result = love.image.newImageData(direction and 1 or #colors, direction and #colors or 1)
for i, color in ipairs(colors) do
local x, y
if direction then
x, y = 0, i - 1
else
x, y = i - 1, 0
end
result:setPixel(x, y, color[1], color[2], color[3], color[4] or 255)
end
result = love.graphics.newImage(result)
result:setFilter('linear', 'linear')
return result
end
local direction = colors.direction or "horizontal"
if direction == "horizontal" then
direction = true
elseif direction == "vertical" then
direction = false
else
error("Invalid direction '" .. tostring(direction) "' for gradient. Horizontal or vertical expected.")
end
local result = love.image.newImageData(direction and 1 or #colors, direction and #colors or 1)
for i, color in ipairs(colors) do
local x, y
if direction then
x, y = 0, i - 1
else
x, y = i - 1, 0
end
result:setPixel(x, y, color[1], color[2], color[3], color[4] or 255)
end
result = love.graphics.newImage(result)
result:setFilter('linear', 'linear')
return result
end
drawinrect
Synopsis
drawinrect(img, x, y, w, h, r, ox, oy, kx, ky)
A convenience function to draw scaled images in a rectangle of absolute size (rather than with a size relative to the size of the image, which is what love.graphics.draw() does). Useful for gradients, because you will almost always want to draw them scaled, and you don't want their bounds to change if the number of colors does.
Source
function drawinrect(img, x, y, w, h, r, ox, oy, kx, ky)
return -- tail call for a little extra bit of efficiency
love.graphics.draw(img, x, y, r, w / img:getWidth(), h / img:getHeight(), ox, oy, kx, ky)
end
return -- tail call for a little extra bit of efficiency
love.graphics.draw(img, x, y, r, w / img:getWidth(), h / img:getHeight(), ox, oy, kx, ky)
end
Examples
draw a 100x100 horizontal rainbow (that is, red on top, purple on bottom) in the center of the screen
require "gradient"
local rainbow = gradient {
direction = 'horizontal';
{255, 0, 0};
{255, 255, 0};
{0, 255, 0};
{0, 255, 255};
{0, 0, 255};
{255, 0, 0};
}
function love.draw()
drawinrect(rainbow, love.graphics.getWidth() / 2 - 50, love.graphics.getHeight() / 2 - 50, 100)
end
local rainbow = gradient {
direction = 'horizontal';
{255, 0, 0};
{255, 255, 0};
{0, 255, 0};
{0, 255, 255};
{0, 0, 255};
{255, 0, 0};
}
function love.draw()
drawinrect(rainbow, love.graphics.getWidth() / 2 - 50, love.graphics.getHeight() / 2 - 50, 100)
end
draw a vertical greyscale spectrum (that is, black on left, white on right) filling the whole screen
require "gradient"
local greyscale = gradient {
direction = 'vertical';
{0, 0, 0};
{255, 255, 255};
}
function love.draw()
drawinrect(greyscale, 0, 0, love.graphics.getWidth(), love.graphics.getHeight())
end
local greyscale = gradient {
direction = 'vertical';
{0, 0, 0};
{255, 255, 255};
}
function love.draw()
drawinrect(greyscale, 0, 0, love.graphics.getWidth(), love.graphics.getHeight())
end
