Initial commit

11 files changed, 542 insertions, 0 deletions

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..5aed0ff
--- /dev/null
+++ b/README.md
@@ -0,0 +1,47 @@
+# QUICKIE
+
+Quickie is an [immediate mode gui][IMGUI] library for LÖVE.
+
+## Example
+
+	local gui = require 'quickie'
+
+	-- widgets are "created" by calling their corresponding functions in love.update.
+	-- if you want to remove a widget, simply don't call the function (just like with
+	-- any other love drawable). widgets dont hold their own state - this is your job:
+	-- 
+	-- sliders have a value and optional a minimum (default = 0) and maximum (default = 1)
+	local slider = {value = 10, min = 0, max = 100}
+	-- input boxes have a text and a cursor position (defaults to end of string)
+	local input = {text = "Hello, World!", cursor = 0}
+	-- checkboxes have only a `checked' status
+	local checkbox = {checked = false}
+
+	function love.update(dt)
+		-- widgets are defined by simply calling them. usually a widget returns true if
+		-- if its value changed or if it was activated (click on button, ...)
+		if gui.Input(input, 10, 10, 300, 20) then
+			print('Text changed:', input.text)
+		end
+
+		if gui.Button('Clear', 320,10,100,20) then
+			input.text = ""
+		end
+
+		-- add more widgets here
+	end
+
+	function love.draw()
+		-- draw the widgets which were "created" in love.update
+		gui.core.draw()
+	end
+
+	function love.keypressed(key,code)
+		-- forward keyboard events to the gui. If you don't want widget tabbing and
+		-- input widgets, skip this line
+		gui.core.keyboard.pressed(key, code)
+	end
+
+## Documentation
+
+TODO
diff --git a/button.lua b/button.lua
new file mode 100644
index 0000000..2374645
--- /dev/null
+++ b/button.lua
@@ -0,0 +1,27 @@
+local core = require((...):match("^(.+)%.[^%.]+") .. '.core')
+
+-- the widget
+return function(title, x,y, w,h, draw)
+	-- Generate unique identifier for gui state update and querying.
+	local id = core.generateID()
+
+	-- The widget mouse-state can be:
+	--   hot (mouse over widget),
+	--   active (mouse pressed on widget) or
+	--   normal (mouse not on widget and not pressed on widget).
+	--
+	-- core.mouse.updateState(id, x,y,w,h) updates the state for this widget.
+	core.mouse.updateState(id, x,y,w,h)
+
+	-- core.makeTabable makes the item focus on tab. Tab order is determied
+	-- by the order you call the widget functions.
+	core.makeTabable(id)
+
+	-- core.registerDraw(id, drawfunction, drawfunction-arguments...)
+	-- shows widget when core.draw() is called.
+	core.registerDraw(id, draw or core.style.Button, title,x,y,w,h)
+
+	return core.mouse.releasedOn(id) or
+	       (core.keyboard.key == 'return' and core.hasKeyFocus(id))
+end
+
diff --git a/checkbox.lua b/checkbox.lua
new file mode 100644
index 0000000..c5f5fce
--- /dev/null
+++ b/checkbox.lua
@@ -0,0 +1,19 @@
+local core = require((...):match("^(.+)%.[^%.]+") .. '.core')
+
+return function(info, x,y, w,h, draw)
+	local id = core.generateID()
+
+	core.mouse.updateState(id, x,y,w,h)
+	core.makeTabable(id)
+	core.registerDraw(id, draw or core.style.Checkbox, info.checked,x,y,w,h)
+
+	local checked = info.checked
+	local key = core.keyboard.key
+	if core.mouse.releasedOn(id) or
+		(core.hasKeyFocus(id) and key == 'return' or key == ' ') then
+		info.checked = not info.checked
+	end
+
+	return info.checked ~= checked
+end
+
diff --git a/core.lua b/core.lua
new file mode 100644
index 0000000..f57caa9
--- /dev/null
+++ b/core.lua
@@ -0,0 +1,153 @@
+-- state
+local context = {maxid = 0}
+local NO_WIDGET = function()end
+
+local function generateID()
+	context.maxid = context.maxid + 1
+	return context.maxid
+end
+
+local function setHot(id) context.hot = id end
+local function isHot(id)  return context.hot == id end
+
+local function setActive(id) context.active = id end
+local function isActive(id)  return context.active == id end
+
+local function setKeyFocus(id) context.keyfocus = id end
+local function hasKeyFocus(id) return context.keyfocus == id end
+
+-- input
+local mouse = {x = 0, y = 0, down = false}
+local keyboard = {key = nil, code = -1}
+
+function mouse.inRect(x,y,w,h)
+	return mouse.x >= x and mouse.x <= x+w and mouse.y >= y and mouse.y <= y+h
+end
+
+function mouse.updateState(id, x,y,w,h)
+	if mouse.inRect(x,y,w,h) then
+		setHot(id)
+		if not context.active and mouse.down then
+			setActive(id)
+		end
+	end
+end
+
+function mouse.releasedOn(id)
+	return not mouse.down and isHot(id) and isActive(id)
+end
+
+function keyboard.pressed(key, code)
+	keyboard.key = key
+	keyboard.code = code
+end
+
+function keyboard.tryGrab(id)
+	if not context.keyfocus then
+		context.keyfocus = id
+	end
+end
+
+local function makeTabable(id)
+	keyboard.tryGrab(id)
+	if hasKeyFocus(id) and keyboard.key == 'tab' then
+		if love.keyboard.isDown('rshift', 'lshift') then
+			setKeyFocus(context.lastwidget)
+		else
+			setKeyFocus(nil)
+		end
+		keyboard.key = nil
+	end
+	context.lastwidget = id
+end
+
+-- helper functions
+local function strictAnd(...)
+	local n = select("#", ...)
+	local ret = true
+	for i = 1,n do ret = select(i, ...) and ret end
+	return ret
+end
+
+local function strictOr(...)
+	local n = select("#", ...)
+	local ret = false
+	for i = 1,n do ret = select(i, ...) or ret end
+	return ret
+end
+
+-- allow packed nil
+local function save_pack(...)
+	return {n = select('#', ...), ...}
+end
+
+local function save_unpack(t, i)
+	i = i or 1
+	if i >= t.n then return t[i] end
+	return t[i], save_unpack(t, i+1)
+end
+
+local draw_items = {n = 0}
+local function registerDraw(id, f, ...)
+	assert(type(f) == 'function' or (getmetatable(f) or {}).__call,
+	       'Drawing function is not a callable type!')
+
+	local state = 'normal'
+	if isHot(id) or hasKeyFocus(id) then
+		state = isActive(id) and 'active' or 'hot'
+	end
+	local rest = save_pack(...)
+	draw_items.n = draw_items.n + 1
+	draw_items[draw_items.n] = function() f(state, save_unpack(rest)) end
+end
+
+-- actually update-and-draw
+local function draw()
+	-- close frame state
+	if not mouse.down then -- released
+		setActive(nil)
+	elseif not context.active then -- clicked outside
+		setActive(NO_WIDGET)
+	end
+
+	for i = 1,draw_items.n do draw_items[i]() end
+
+	-- prepare for next frame
+	draw_items.n = 0
+	context.maxid = 0
+
+	-- update mouse status
+	setHot(nil)
+	mouse.x, mouse.y = love.mouse.getPosition()
+	mouse.down = love.mouse.isDown('l')
+
+	-- clear keyboard focus if nobody wants it
+	if keyboard.key == 'tab' then
+		context.keyboardfocus = nil
+	end
+	keyboard.key, keyboard.code = nil, -1
+end
+
+return {
+	mouse        = mouse,
+	keyboard     = keyboard,
+
+	generateID   = generateID,
+	setHot       = setHot,
+	setActive    = setActive,
+	setKeyFocus  = setKeyFocus,
+	isHot        = isHot,
+	isActive     = isActive,
+	hasKeyFocus  = hasKeyFocus,
+	makeTabable  = makeTabable,
+
+	style        = require((...):match("^(.+)%.[^%.]+") .. '.style-default'),
+	color        = color,
+	registerDraw = registerDraw,
+	draw         = draw,
+
+	strictAnd    = strictAnd,
+	strictOr     = strictOr,
+	save_pack    = save_pack,
+	save_unpack  = save_unpack,
+}
diff --git a/imgui.love b/imgui.love
new file mode 100644
index 0000000..720c9b1
--- /dev/null
+++ b/imgui.love
diff --git a/init.lua b/init.lua
new file mode 100644
index 0000000..3b4e70c
--- /dev/null
+++ b/init.lua
@@ -0,0 +1,11 @@
+local BASE = (...) .. '.'
+
+return {
+	core     = require(BASE .. 'core'),
+	Button   = require(BASE .. 'button'),
+	Slider   = require(BASE .. 'slider'),
+	Slider2D = require(BASE .. 'slider2d'),
+	Label    = require(BASE .. 'label'),
+	Input    = require(BASE .. 'input'),
+	Checkbox = require(BASE .. 'checkbox')
+}
diff --git a/input.lua b/input.lua
new file mode 100644
index 0000000..2ba29b5
--- /dev/null
+++ b/input.lua
@@ -0,0 +1,43 @@
+local core = require((...):match("^(.+)%.[^%.]+") .. '.core')
+
+return function(info, x,y,w,h, draw)
+	info.text = info.text or ""
+	info.cursor = math.min(info.cursor or info.text:len(), info.text:len())
+
+	local id = core.generateID()
+	core.mouse.updateState(id, x,y,w,h)
+	core.makeTabable(id)
+	if core.isActive(id) then core.setKeyFocus(id) end
+
+	core.registerDraw(id, draw or core.style.Input, info.text, info.cursor, x,y,w,h)
+
+	local changed = false
+	-- editing
+	if core.keyboard.key == 'backspace' then
+		info.text = info.text:sub(1,info.cursor-1) .. info.text:sub(info.cursor+1)
+		info.cursor = math.max(0, info.cursor-1)
+		changed = true
+	elseif core.keyboard.key == 'delete' then
+		info.text = info.text:sub(1,info.cursor) .. info.text:sub(info.cursor+2)
+		info.cursor = math.min(info.text:len(), info.cursor)
+		changed = true
+	-- movement
+	elseif core.keyboard.key == 'left' then
+		info.cursor = math.max(0, info.cursor-1)
+	elseif core.keyboard.key == 'right' then
+		info.cursor = math.min(info.text:len(), info.cursor+1)
+	elseif core.keyboard.key == 'home' then
+		info.cursor = 0
+	elseif core.keyboard.key == 'end' then
+		info.cursor = info.text:len()
+	-- input
+	elseif core.keyboard.code >= 32 and core.keyboard.code < 127 then
+		local left = info.text:sub(1,info.cursor)
+		local right =  info.text:sub(info.cursor+1)
+		info.text = table.concat{left, string.char(core.keyboard.code), right}
+		info.cursor = info.cursor + 1
+		changed = true
+	end
+
+	return changed
+end
diff --git a/label.lua b/label.lua
new file mode 100644
index 0000000..76f3c92
--- /dev/null
+++ b/label.lua
@@ -0,0 +1,9 @@
+local core = require((...):match("^(.+)%.[^%.]+") .. '.core')
+
+return function(text, x,y,w,h,align, draw)
+	local id = core.generateID()
+	w, h, align = w or 0, h or 0, align or 'left'
+	core.registerDraw(id, draw or core.style.Label,  text,x,y,w,h,align)
+	return false
+end
+
diff --git a/slider.lua b/slider.lua
new file mode 100644
index 0000000..ae75c01
--- /dev/null
+++ b/slider.lua
@@ -0,0 +1,44 @@
+local core = require((...):match("^(.+)%.[^%.]+") .. '.core')
+
+return function(info, x,y,w,h, draw)
+	assert(type(info) == 'table' and info.value, "Incomplete slider value info")
+	info.min = info.min or 0
+	info.max = info.max or math.max(info.value, 1)
+	info.step = info.step or (info.max - info.min) / 50
+	local fraction = (info.value - info.min) / (info.max - info.min)
+
+	local id = core.generateID()
+	core.mouse.updateState(id, x,y,w,h)
+	core.makeTabable(id)
+	core.registerDraw(id,draw or core.style.Slider, fraction, x,y,w,h, info.vertical)
+
+	-- mouse update
+	if core.isActive(id) then
+		core.setKeyFocus(id)
+		if info.vertical then
+			fraction = math.min(1, math.max(0, (y - core.mouse.y + h) / h))
+		else
+			fraction = math.min(1, math.max(0, (core.mouse.x - x) / w))
+		end
+		local v = fraction * (info.max - info.min) + info.min
+		if v ~= info.value then
+			info.value = v
+			return true
+		end
+	end
+
+	-- keyboard update
+	local changed = false
+	if core.hasKeyFocus(id) then
+		local keys = info.vertical and {'up', 'down'} or {'right', 'left'}
+		if core.keyboard.key == keys[1] then
+			info.value = math.min(info.max, info.value + info.step)
+			changed = true
+		elseif core.keyboard.key == keys[2] then
+			info.value = math.max(info.min, info.value - info.step)
+			changed = true
+		end
+	end
+
+	return changed
+end
diff --git a/slider2d.lua b/slider2d.lua
new file mode 100644
index 0000000..023d16f
--- /dev/null
+++ b/slider2d.lua
@@ -0,0 +1,55 @@
+local core = require((...):match("^(.+)%.[^%.]+") .. '.core')
+
+return function(info, x,y,w,h, draw)
+	assert(type(info) == 'table' and type(info.value) == "table", "Incomplete slider value info")
+	info.min = info.min or {x = 0, y = 0}
+	info.max = info.max or {x = math.max(info.value.x or 0, 1), y = math.max(info.value.y or 0, 1)}
+	info.step = info.step or {x = (info.max.x - info.min.x)/50, y = (info.max.y - info.min.y)/50}
+	local fraction = {
+		x = (info.value.x - info.min.x) / (info.max.x - info.min.x),
+		y = (info.value.y - info.min.y) / (info.max.y - info.min.y),
+	}
+
+	local id = core.generateID()
+	core.mouse.updateState(id, x,y,w,h)
+	core.makeTabable(id)
+	core.registerDraw(id,draw or core.style.Slider2D, fraction, x,y,w,h)
+
+	-- update value
+	if core.isActive(id) then
+		core.setKeyFocus(id)
+		fraction = {
+			x = (core.mouse.x - x) / w,
+			y = (core.mouse.y - y) / h,
+		}
+		fraction.x = math.min(1, math.max(0, fraction.x))
+		fraction.y = math.min(1, math.max(0, fraction.y))
+		local v = {
+			x = fraction.x * (info.max.x - info.min.x) + info.min.x,
+			y = fraction.y * (info.max.y - info.min.y) + info.min.y,
+		}
+		if v.x ~= info.value.x or v.y ~= info.value.y then
+			info.value = v
+			return true
+		end
+	end
+
+	local changed = false
+	if core.hasKeyFocus(id) then
+		if core.keyboard.key == 'down' then
+			info.value.y = math.min(info.max.y, info.value.y + info.step.y)
+			changed = true
+		elseif core.keyboard.key == 'up' then
+			info.value.y = math.max(info.min.y, info.value.y - info.step.y)
+			changed = true
+		end
+		if core.keyboard.key == 'right' then
+			info.value.x = math.min(info.max.x, info.value.x + info.step.x)
+			changed = true
+		elseif core.keyboard.key == 'left' then
+			info.value.x = math.max(info.min.x, info.value.x - info.step.x)
+			changed = true
+		end
+	end
+	return changed
+end
diff --git a/style-default.lua b/style-default.lua
new file mode 100644
index 0000000..7c85e46
--- /dev/null
+++ b/style-default.lua
@@ -0,0 +1,134 @@
+-- default style
+local color = {
+	normal = {bg = {128,128,128,200}, fg = {59,59,59,200}},
+	hot    = {bg = {145,153,153,200}, fg = {60,61,54,200}},
+	active = {bg = {145,153,153,255}, fg = {60,61,54,255}}
+}
+
+-- load default font
+if not love.graphics.getFont() then
+	love.graphics.setFont(love.graphics.newFont(12))
+end
+
+local function Button(state, title, x,y,w,h)
+	local c = color[state]
+	if state ~= 'normal' then
+		love.graphics.setColor(c.fg)
+		love.graphics.rectangle('fill', x+3,y+3,w,h)
+	end
+	love.graphics.setColor(c.bg)
+	love.graphics.rectangle('fill', x,y,w,h)
+	love.graphics.setColor(c.fg)
+	local f = love.graphics.getFont()
+	love.graphics.print(title, x + (w-f:getWidth(title))/2, y + (h-f:getHeight(title))/2)
+end
+
+local function Label(state, text, x,y,w,h,align)
+	local c = color[state]
+	love.graphics.setColor(c.fg)
+	local f = assert(love.graphics.getFont())
+	if align == 'center' then
+		x = x + (w - f:getWidth(text))/2
+		y = y + (h - f:getHeight(text))/2
+	elseif align == 'right' then
+		x = x + w - f:getWidth(text)
+		y = y + h - f:getHeight(text)
+	end
+	love.graphics.print(text, x,y)
+end
+
+local function Slider(state, fraction, x,y,w,h, vertical)
+	local c = color[state]
+	if state ~= 'normal' then
+		love.graphics.setColor(c.fg)
+		love.graphics.rectangle('fill', x+3,y+3,w,h)
+	end
+	love.graphics.setColor(c.bg)
+	love.graphics.rectangle('fill', x,y,w,h)
+
+	love.graphics.setColor(c.fg)
+	local hw,hh = w,h
+	if vertical then
+		hh = h * fraction
+		y = y + (h - hh)
+	else
+		hw = w * fraction
+	end
+	love.graphics.rectangle('fill', x,y,hw,hh)
+end
+
+local function Slider2D(state, fraction, x,y,w,h, vertical)
+	local c = color[state]
+	if state ~= 'normal' then
+		love.graphics.setColor(c.fg)
+		love.graphics.rectangle('fill', x+3,y+3,w,h)
+	end
+	love.graphics.setColor(c.bg)
+	love.graphics.rectangle('fill', x,y,w,h)
+
+	-- draw quadrants
+	local lw = love.graphics.getLineWidth()
+	love.graphics.setLineWidth(1)
+	love.graphics.setColor(c.fg[1], c.fg[2], c.fg[3], math.min(c.fg[4], 127))
+	love.graphics.line(x+w/2,y, x+w/2,y+h)
+	love.graphics.line(x,y+h/2, x+w,y+h/2)
+	love.graphics.setLineWidth(lw)
+
+	-- draw cursor
+	local xx = x + fraction.x * w
+	local yy = y + fraction.y * h
+	love.graphics.setColor(c.fg)
+	love.graphics.circle('fill', xx,yy,4,4)
+end
+
+local function Input(state, text, cursor, x,y,w,h)
+	local c = color[state]
+	if state ~= 'normal' then
+		love.graphics.setColor(c.fg)
+		love.graphics.rectangle('fill', x+3,y+3,w,h)
+	end
+	love.graphics.setColor(c.bg)
+	love.graphics.rectangle('fill', x,y,w,h)
+	love.graphics.setColor(c.fg)
+
+	local lw = love.graphics.getLineWidth()
+	love.graphics.setLineWidth(1)
+	love.graphics.rectangle('line', x,y,w,h)
+
+	local f = love.graphics.getFont()
+	local th = f:getHeight(text)
+	local cursorPos = x + 2 + f:getWidth(text:sub(1,cursor))
+
+	love.graphics.print(text, x+2,y+(h-th)/2)
+	love.graphics.line(cursorPos, y+4, cursorPos, y+h-4)
+
+	love.graphics.setLineWidth(lw)
+end
+
+local function Checkbox(state, checked, x,y,w,h)
+	local c = color[state]
+	if state ~= 'normal' then
+		love.graphics.setColor(c.fg)
+		love.graphics.rectangle('fill', x+3,y+3,w,h)
+	end
+	love.graphics.setColor(c.bg)
+	love.graphics.rectangle('fill', x,y,w,h)
+	love.graphics.setColor(c.fg)
+	love.graphics.rectangle('line', x,y,w,h)
+	if checked then
+		local r = math.max(math.min(w/2,h/2) - 3, 2)
+		love.graphics.circle('fill', x+w/2,y+h/2,r)
+	end
+end
+
+
+-- the style
+return {
+	color    = color,
+	Button   = Button,
+	Label    = Label,
+	Slider   = Slider,
+	Slider2D = Slider2D,
+	Input    = Input,
+	Checkbox = Checkbox,
+}