alunizaje/assets/scripts/vendor/gamera.lua
Andros Fenollosa 5fb3cd8d47 add spaceship
2016-11-12 13:49:24 +01:00

209 lines
5.7 KiB
Lua

-- gamera.lua v1.0.1
-- Copyright (c) 2012 Enrique García Cota
-- Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
-- The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-- Based on YaciCode, from Julien Patte and LuaObject, from Sebastien Rocca-Serra
local gamera = {}
-- Private attributes and methods
local gameraMt = {__index = gamera}
local abs, min, max = math.abs, math.min, math.max
local function clamp(x, minX, maxX)
return x < minX and minX or (x>maxX and maxX or x)
end
local function checkNumber(value, name)
if type(value) ~= 'number' then
error(name .. " must be a number (was: " .. tostring(value) .. ")")
end
end
local function checkPositiveNumber(value, name)
if type(value) ~= 'number' or value <=0 then
error(name .. " must be a positive number (was: " .. tostring(value) ..")")
end
end
local function checkAABB(l,t,w,h)
checkNumber(l, "l")
checkNumber(t, "t")
checkPositiveNumber(w, "w")
checkPositiveNumber(h, "h")
end
local function getVisibleArea(self, scale)
scale = scale or self.scale
local sin, cos = abs(self.sin), abs(self.cos)
local w,h = self.w / scale, self.h / scale
w,h = cos*w + sin*h, sin*w + cos*h
return min(w,self.ww), min(h, self.wh)
end
local function cornerTransform(self, x,y)
local scale, sin, cos = self.scale, self.sin, self.cos
x,y = x - self.x, y - self.y
x,y = -cos*x + sin*y, -sin*x - cos*y
return self.x - (x/scale + self.l), self.y - (y/scale + self.t)
end
local function adjustPosition(self)
local wl,wt,ww,wh = self.wl, self.wt, self.ww, self.wh
local w,h = getVisibleArea(self)
local w2,h2 = w*0.5, h*0.5
local left, right = wl + w2, wl + ww - w2
local top, bottom = wt + h2, wt + wh - h2
self.x, self.y = clamp(self.x, left, right), clamp(self.y, top, bottom)
end
local function adjustScale(self)
local w,h,ww,wh = self.w, self.h, self.ww, self.wh
local rw,rh = getVisibleArea(self, 1) -- rotated frame: area around the window, rotated without scaling
local sx,sy = rw/ww, rh/wh -- vert/horiz scale: minimun scales that the window needs to occupy the world
local rscale = max(sx,sy)
self.scale = max(self.scale, rscale)
end
-- Public interface
function gamera.new(l,t,w,h)
local sw,sh = love.graphics.getWidth(), love.graphics.getHeight()
local cam = setmetatable({
x=0, y=0,
scale=1,
angle=0, sin=math.sin(0), cos=math.cos(0),
l=0, t=0, w=sw, h=sh, w2=sw*0.5, h2=sh*0.5
}, gameraMt)
cam:setWorld(l,t,w,h)
return cam
end
function gamera:setWorld(l,t,w,h)
checkAABB(l,t,w,h)
self.wl, self.wt, self.ww, self.wh = l,t,w,h
adjustPosition(self)
end
function gamera:setWindow(l,t,w,h)
checkAABB(l,t,w,h)
self.l, self.t, self.w, self.h, self.w2, self.h2 = l,t,w,h, w*0.5, h*0.5
adjustPosition(self)
end
function gamera:setPosition(x,y)
checkNumber(x, "x")
checkNumber(y, "y")
self.x, self.y = x,y
adjustPosition(self)
end
function gamera:setScale(scale)
checkNumber(scale, "scale")
self.scale = scale
adjustScale(self)
adjustPosition(self)
end
function gamera:setAngle(angle)
checkNumber(angle, "angle")
self.angle = angle
self.cos, self.sin = math.cos(angle), math.sin(angle)
adjustScale(self)
adjustPosition(self)
end
function gamera:getWorld()
return self.wl, self.wt, self.ww, self.wh
end
function gamera:getWindow()
return self.l, self.t, self.w, self.h
end
function gamera:getPosition()
return self.x, self.y
end
function gamera:getScale()
return self.scale
end
function gamera:getAngle()
return self.angle
end
function gamera:getVisible()
local w,h = getVisibleArea(self)
return self.x - w*0.5, self.y - h*0.5, w, h
end
function gamera:getVisibleCorners()
local x,y,w2,h2 = self.x, self.y, self.w2, self.h2
local x1,y1 = cornerTransform(self, x-w2,y-h2)
local x2,y2 = cornerTransform(self, x+w2,y-h2)
local x3,y3 = cornerTransform(self, x+w2,y+h2)
local x4,y4 = cornerTransform(self, x-w2,y+h2)
return x1,y1,x2,y2,x3,y3,x4,y4
end
function gamera:draw(f)
love.graphics.setScissor(self:getWindow())
love.graphics.push()
local scale = self.scale
love.graphics.scale(scale)
love.graphics.translate((self.w2 + self.l) / scale, (self.h2+self.t) / scale)
love.graphics.rotate(-self.angle)
love.graphics.translate(-self.x, -self.y)
f(self:getVisible())
love.graphics.pop()
love.graphics.setScissor()
end
function gamera:toWorld(x,y)
local scale, sin, cos = self.scale, self.sin, self.cos
x,y = (x - self.w2 - self.l) / scale, (y - self.h2 - self.t) / scale
x,y = cos*x - sin*y, sin*x + cos*y
return x + self.x, y + self.y
end
function gamera:toScreen(x,y)
local scale, sin, cos = self.scale, self.sin, self.cos
x,y = x - self.x, y - self.y
x,y = cos*x + sin*y, -sin*x + cos*y
return scale * x + self.w2 + self.l, scale * y + self.h2 + self.t
end
return gamera