Sphere wallpaper

Wallpapers/Sphere.wlp/Main.lua

@@ -0,0 +1,207 @@
+local screen = require("Screen")
+local color = require("Color")
+local filesystem = require("Filesystem")
+local system = require("System")
+local GUI = require("GUI")
+
+--------------------------------------------------------------------------------
+
+local workspace, wallpaper = select(1, ...), select(2, ...)
+
+local configPath = filesystem.path(system.getCurrentScript()) .. "Config.cfg"
+
+local config = {
+    backgroundColor = 0x000000,
+
+    sphereRadius = 20,
+    sphereColor = 0xFFFFFF,
+    spherePos = {20, 0, 0},
+    
+    lightColor = 0xFFFF40,
+    diffuseIntensity = 12,
+    ambientIntensity = 0.1,
+    specularIntensity = 0.5,
+    specularPower = 1,
+
+    speed = 5
+}
+
+if filesystem.exists(configPath) then
+	for key, value in pairs(filesystem.readTable(configPath)) do
+		config[key] = value
+	end
+end
+
+local function saveConfig()
+	filesystem.writeTable(configPath, config)
+end
+
+--------------------------------------------------------------------------------
+
+local function vecNormalize(vec)
+    local length = (vec[1]^2 + vec[2]^2 + vec[3]^2)^0.5
+    if length < 0.00001 then 
+        length = 0.00001 
+    end
+
+    return {
+        vec[1] / length,
+        vec[2] / length,
+        vec[3] / length
+    }
+end
+
+local function vecSubtract(a, b)
+    return {a[1] - b[1], a[2] - b[2], a[3] - b[3]}
+end
+
+local function vecAdd(a, b)
+    return {a[1] + b[1], a[2] + b[2], a[3] + b[3]}
+end
+
+local function vecScalarProduct(vec, scalar)
+    return {vec[1] * scalar, vec[2] * scalar, vec[3] * scalar}
+end
+
+local function vecHadamardProduct(a, b)
+    return {a[1] * b[1], a[2] * b[2], a[3] * b[3]}
+end
+
+local function vecDotProduct(a, b)
+    return a[1] * b[1] + a[2] * b[2] + a[3] * b[3]
+end
+
+local function vecSqrDistance(a, b)
+    return (a[1] - b[1])^2 + (a[2] - b[2])^2 + (a[3] - b[3])^2
+end
+
+local function vecIntegerToRGB(integer)
+    local r, g, b = color.integerToRGB(integer)
+    return {
+        r / 0xFF,
+        g / 0xFF,
+        b / 0xFF
+    }
+end
+
+local function vecRGBToInteger(vec)
+    return color.RGBToInteger(
+        math.floor(vec[1] * 0xFF), 
+        math.floor(vec[2] * 0xFF), 
+        math.floor(vec[3] * 0xFF)
+    )
+end
+
+local function clamp(value, min, max)
+    if value < min then return min end
+    if value > max then return max end
+    return value
+end
+
+--------------------------------------------------------------------------------
+
+local lightSpinRadius, sphereRadiusSqr, lightColorVec, sphereColorVec, colorProduct, viewPos, startTime
+
+local function precalculateValues()
+    lightSpinRadius = config.sphereRadius + 5
+    sphereRadiusSqr = config.sphereRadius^2
+    lightColorVec = vecIntegerToRGB(config.lightColor)
+    sphereColorVec = vecIntegerToRGB(config.sphereColor)
+    colorProduct = vecHadamardProduct(lightColorVec, sphereColorVec)
+    viewPos = {0, 0, 500}
+    startTime = computer.uptime()
+end
+
+precalculateValues()
+
+--------------------------------------------------------------------------------
+
+wallpaper.draw = function(wallpaper)
+    local t = config.speed * (computer.uptime() - startTime) / 10
+    
+    local lightPos = {lightSpinRadius * math.cos(t), lightSpinRadius * 0.5 * math.cos(t), lightSpinRadius * math.sin(t)}
+    local cx, cy = math.floor(wallpaper.width / 2), wallpaper.height
+
+    screen.drawRectangle(wallpaper.x, wallpaper.y, wallpaper.width, wallpaper.height, config.backgroundColor, 0, " ")
+
+    for x = -config.sphereRadius, config.sphereRadius do
+        for y = -config.sphereRadius, config.sphereRadius do
+            if x^2 + y^2 <= sphereRadiusSqr then
+                local fragPos = {x, y, (config.sphereRadius^2 - x^2 - y^2)^0.5}
+
+                local L  = vecNormalize(vecSubtract(lightPos, fragPos))
+                local N  = vecNormalize(fragPos)
+                local V  = vecNormalize(vecSubtract(viewPos, fragPos))
+                local LN = vecDotProduct(L, N)
+                local Lr = vecNormalize(vecSubtract(vecScalarProduct(N, 2 * LN), L))
+
+                local distance = vecSqrDistance(lightPos, fragPos)
+
+                local diffuse = clamp((LN / distance) * config.diffuseIntensity, 0, 1)
+                local specular = clamp(vecDotProduct(Lr, V), 0, 1)^config.specularPower * config.specularIntensity
+
+                local fragColor = vecScalarProduct(colorProduct, diffuse)
+                fragColor = vecAdd(fragColor, vecScalarProduct(colorProduct, config.ambientIntensity))
+                fragColor = vecAdd(fragColor, vecScalarProduct(lightColorVec, specular))
+
+                screen.semiPixelSet(cx + x, cy + y, vecRGBToInteger(fragColor))
+            end
+        end
+    end
+
+    if lightPos[1]^2 + lightPos[2]^2 > sphereRadiusSqr or lightPos[3] > (config.sphereRadius^2 - lightPos[1]^2 - lightPos[2]^2)^0.5 then
+        screen.semiPixelSet(cx + math.floor(lightPos[1]), cy + math.floor(lightPos[2]), config.lightColor)
+    end
+end
+
+wallpaper.configure = function(layout)
+    local function addColorSelector(configValue, title)
+        layout:addChild(GUI.colorSelector(1, 1, 36, 3, config[configValue], title)).onColorSelected = function(_, object)
+            config[configValue] = object.color
+            saveConfig()
+            precalculateValues()
+        end
+    end
+
+    local function addSlider(configValue, title, minValue, maxValue, roundValues)
+        local slider = layout:addChild(
+            GUI.slider(
+                1, 1, 
+                36,
+                0x66DB80, 
+                0xE1E1E1, 
+                0xFFFFFF, 
+                0xA5A5A5, 
+                minValue, maxValue, 
+                config[configValue], 
+                false,
+                title
+            )
+        )
+        
+        slider.roundValues = roundValues
+        slider.onValueChanged = function()
+            if roundValues then
+                config[configValue] = math.floor(slider.value)
+            else
+                config[configValue] = slider.value
+            end
+
+            saveConfig()
+            precalculateValues()
+        end
+    end
+
+    addColorSelector("backgroundColor", "Background color")
+    addColorSelector("sphereColor",     "Sphere color"    )
+    addColorSelector("lightColor",      "Light color"     )
+
+    addSlider("sphereRadius",      "Sphere radius: ",      5, 50, true )
+    addSlider("diffuseIntensity",  "Diffuse intensity: ",  0, 50, false)
+    addSlider("ambientIntensity",  "Ambient intensity: ",  0, 1,  false)
+    addSlider("specularIntensity", "Specular intensity: ", 0, 5,  false)
+    addSlider("specularPower",     "Specular power: ",     1, 50, true )
+    addSlider("speed",             "Speed: ",              1, 10, false)
+end
+
+--------------------------------------------------------------------------------