automobiles_pck/automobiles_lib/painter.lua

--[[
Copyright (C) 2022 Alexsandro Percy
Copyright (C) 2018 Hume2

 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.
]]--

--[[painting functions adapted from bike mod]]--

local function is_hex(color)
	if color:len() ~= 7 then return nil end
	return color:match("#%x%x%x%x%x%x")
end

-- hex translation
local function hex_to_rgb(hex_value)
	hex_value = hex_value:gsub("#","")
	local rgb = {
		r = tonumber("0x"..hex_value:sub(1,2)),
		g = tonumber("0x"..hex_value:sub(3,4)),
		b = tonumber("0x"..hex_value:sub(5,6)),
	}
	return rgb
end

local function rgb_to_hex(r, g, b)
	return string.format("#%02X%02X%02X", r, g, b)
end

-- Need to convert between 1000 units and 256
local function from_slider_rgb(value)
	value = tonumber(value)
	return math.floor((255/1000*value)+0.5)
end

-- ...and back
local function to_slider_rgb(value)
    if value then
    	return 1000/255*value
    end
    return 1000/255*255
end

-- Painter formspec
local function painter_form(itemstack, player)
	local meta = itemstack:get_meta()
	local color = meta:get_string("paint_color")
	if color == nil or color == "" then
		color = "#FFFFFF"
		meta:set_string("paint_color", color)
		meta:set_string("description", "Automobiles Painter ("..color:upper()..")")
	end
	local rgb = hex_to_rgb(color)
	minetest.show_formspec(player:get_player_name(), "automobiles_lib:painter",
		-- Init formspec
		"size[6,4.7;true]"..
		"position[0.5, 0.45]"..
		-- Preview
		"label[0,0;Preview:]"..
		"image[1.2,0;2,2;automobiles_painting.png^[colorize:"..color..":255]"..
		-- RGB sliders
		"scrollbar[0,2;5,0.3;horizontal;r;"..tostring(to_slider_rgb(rgb.r)).."]"..
		"label[5.1,1.9;R: "..tostring(rgb.r).."]"..
		"scrollbar[0,2.6;5,0.3;horizontal;g;"..tostring(to_slider_rgb(rgb.g)).."]"..
		"label[5.1,2.5;G: "..tostring(rgb.g).."]"..
		"scrollbar[0,3.2;5,0.3;horizontal;b;"..tostring(to_slider_rgb(rgb.b)).."]"..
		"label[5.1,3.1;B: "..tostring(rgb.b).."]"..
		-- Hex field
		"field[0.3,4.5;2,0.8;hex;Hex Color;"..color.."]"..
		"button[4.05,4.1;2,1;set;Set color]"
	)
end

minetest.register_on_player_receive_fields(function(player, formname, fields)
	if formname == "automobiles_lib:painter" then
		local itemstack = player:get_wielded_item()
		if fields.set then
			if itemstack:get_name() == "automobiles_lib:painter" then
				local meta = itemstack:get_meta()
				local hex = fields.hex
                if hex then
				    if is_hex(hex) == nil then
					    hex = "#FFFFFF"
				    end
				    -- Save color data to painter (rgba sliders will adjust to hex/alpha too!)
				    meta:set_string("paint_color", hex)
				    meta:set_string("description", "Automobiles Painter ("..hex:upper()..")")
				    player:set_wielded_item(itemstack)
				    painter_form(itemstack, player)
				    return
                end
			end
		end
		if fields.r or fields.g or fields.b then
			if itemstack:get_name() == "automobiles_lib:painter" then
				-- Save on slider adjustment (hex/alpha will adjust to match the rgba!)
				local meta = itemstack:get_meta()
				local function sval(value)
					return from_slider_rgb(value:gsub(".*:", ""))
				end
				meta:set_string("paint_color", rgb_to_hex(sval(fields.r),sval(fields.g),sval(fields.b)))
				-- Keep track of what this painter is painting
				meta:set_string("description", "Automobiles Painter ("..meta:get_string("paint_color"):upper()..")")
				player:set_wielded_item(itemstack)
				painter_form(itemstack, player)
			end
		end
	end
end)
--[[end of adaptations]]--


-- Make the actual thingy
minetest.register_tool("automobiles_lib:painter", {
	description = "Automobiles Painter",
	inventory_image = "automobiles_painter.png",
	wield_scale = {x = 2, y = 2, z = 1},
	on_place = painter_form,
	on_secondary_use = painter_form,
})

minetest.register_craft({
	output = "automobiles_lib:painter",
	recipe = {
		{"", "default:steel_ingot", ""},
		{"dye:red", "dye:green", "dye:blue"},
		{"", "default:steel_ingot", ""},
	},
})