79 lines
2.4 KiB
Lua
79 lines
2.4 KiB
Lua
--[[
|
|
Public domain:
|
|
|
|
Copyright (C) 2017 by Matthias Richter <vrld@vrld.org>
|
|
|
|
Permission to use, copy, modify, and/or distribute this software for any
|
|
purpose with or without fee is hereby granted.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
|
|
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
|
FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
|
|
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
|
|
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
PERFORMANCE OF THIS SOFTWARE.
|
|
]]--
|
|
|
|
return function(moonshine)
|
|
-- Barrel distortion adapted from Daniel Oaks (see commit cef01b67fd)
|
|
-- Added feather to mask out outside of distorted texture
|
|
local distortionFactor
|
|
local shader = love.graphics.newShader[[
|
|
extern vec2 distortionFactor;
|
|
extern vec2 scaleFactor;
|
|
extern number feather;
|
|
|
|
vec4 effect(vec4 color, Image tex, vec2 uv, vec2 px) {
|
|
// to barrel coordinates
|
|
uv = uv * 2.0 - vec2(1.0);
|
|
|
|
// distort
|
|
uv *= scaleFactor;
|
|
uv += (uv.yx*uv.yx) * uv * (distortionFactor - 1.0);
|
|
number mask = (1.0 - smoothstep(1.0-feather,1.0,abs(uv.x)))
|
|
* (1.0 - smoothstep(1.0-feather,1.0,abs(uv.y)));
|
|
|
|
// to cartesian coordinates
|
|
uv = (uv + vec2(1.0)) / 2.0;
|
|
|
|
return color * Texel(tex, uv) * mask;
|
|
}
|
|
]]
|
|
|
|
local setters = {}
|
|
|
|
setters.distortionFactor = function(v)
|
|
assert(type(v) == "table" and #v == 2, "Invalid value for `distortionFactor'")
|
|
distortionFactor = {unpack(v)}
|
|
shader:send("distortionFactor", v)
|
|
end
|
|
|
|
setters.x = function(v) setters.distortionFactor{v, distortionFactor[2]} end
|
|
setters.y = function(v) setters.distortionFactor{distortionFactor[1], v} end
|
|
|
|
setters.scaleFactor = function(v)
|
|
if type(v) == "table" and #v == 2 then
|
|
shader:send("scaleFactor", v)
|
|
elseif type(v) == "number" then
|
|
shader:send("scaleFactor", {v,v})
|
|
else
|
|
error("Invalid value for `scaleFactor'")
|
|
end
|
|
end
|
|
|
|
setters.feather = function(v) shader:send("feather", v) end
|
|
|
|
local defaults = {
|
|
distortionFactor = {1.06, 1.065},
|
|
feather = 0.02,
|
|
scaleFactor = 1,
|
|
}
|
|
|
|
return moonshine.Effect{
|
|
name = "crt",
|
|
shader = shader,
|
|
setters = setters,
|
|
defaults = defaults
|
|
}
|
|
end
|