fix: hq2x results graphical issue on some systems

assets/mods/basegame/locales/en/calendar.json

@@ -0,0 +1,31 @@
+{
+  "GAME_ITEM_CALENDAR": "Calendar",
+  "MENU_CALENDAR_CALENDAR": "Calendar",
+  "MENU_CALENDAR_EVENTS": "Events",
+  "MENU_CALENDAR_ADD_NEW_EVENT": "Add New Event…",
+  "CONTEXT_CALENDAR_SEASON_SPRING": "Spring",
+  "CONTEXT_CALENDAR_SEASON_SUMMER": "Summer",
+  "CONTEXT_CALENDAR_SEASON_AUTUMN": "Autumn",
+  "CONTEXT_CALENDAR_SEASON_WINTER": "Winter",
+  "CONTEXT_CALENDAR_SEASON_SPRI": "Spri",
+  "CONTEXT_CALENDAR_SEASON_SUMM": "Summ",
+  "CONTEXT_CALENDAR_SEASON_AUTM": "Autm",
+  "CONTEXT_CALENDAR_SEASON_WINT": "Wint",
+
+  "CONTEXT_CALENDAR_DAY_MONDAG_DNT": "Mondag",
+  "CONTEXT_CALENDAR_DAY_TYSDAG_DNT": "Tysdag",
+  "CONTEXT_CALENDAR_DAY_MIDTVEKE_DNT": "Midtveke",
+  "CONTEXT_CALENDAR_DAY_TORSDAG_DNT": "Torsdag",
+  "CONTEXT_CALENDAR_DAY_FREDAG_DNT": "Fredag",
+  "CONTEXT_CALENDAR_DAY_LAURDAG_DNT": "Laurdag",
+  "CONTEXT_CALENDAR_DAY_SUNDAG_DNT": "Sundag",
+  "CONTEXT_CALENDAR_DAY_VERDDAG_DNT": "Verddag",
+  "CONTEXT_CALENDAR_DAY_MON_DNT": "Mon",
+  "CONTEXT_CALENDAR_DAY_TYS_DNT": "Tys",
+  "CONTEXT_CALENDAR_DAY_MID_DNT": "Mid",
+  "CONTEXT_CALENDAR_DAY_TOR_DNT": "Tor",
+  "CONTEXT_CALENDAR_DAY_FRE_DNT": "Fre",
+  "CONTEXT_CALENDAR_DAY_LAU_DNT": "Lau",
+  "CONTEXT_CALENDAR_DAY_SUN_DNT": "Sun",
+  "CONTEXT_CALENDAR_DAY_VER_DNT": "Ver"
+}

assets/mods/basegame/locales/koKR/calendar.json

@@ -0,0 +1,14 @@
+{
+  "GAME_ITEM_CALENDAR": "달력",
+  "MENU_CALENDAR_CALENDAR": "달력",
+  "MENU_CALENDAR_EVENTS": "일정",
+  "MENU_CALENDAR_ADD_NEW_EVENT": "새 일정 추가…",
+  "CONTEXT_CALENDAR_SEASON_SPRING": "봄",
+  "CONTEXT_CALENDAR_SEASON_SUMMER": "여름",
+  "CONTEXT_CALENDAR_SEASON_AUTUMN": "가을",
+  "CONTEXT_CALENDAR_SEASON_WINTER": "겨울",
+  "CONTEXT_CALENDAR_SEASON_SPRI": "봄",
+  "CONTEXT_CALENDAR_SEASON_SUMM": "여름",
+  "CONTEXT_CALENDAR_SEASON_AUTM": "가을",
+  "CONTEXT_CALENDAR_SEASON_WINT": "겨울"
+}

src/net/torvald/colourutil/CIEXYZUtil.kt

@@ -192,6 +192,16 @@ fun CIEXYZ.toColorRaw(): Color {
     return Color(rgb.r, rgb.g, rgb.b, rgb.alpha)
 }
 
+fun CIEXYZ.toYXY(): CIEYXY {
+    val dot = this.X + this.Y + this.Z
+    return CIEYXY(
+        this.Y,
+        this.X / dot,
+        this.Y / dot,
+        this.alpha
+    )
+}
+
 fun CIEYXY.toXYZ(): CIEXYZ {
     return CIEXYZ(x * yy / y, yy, (1f - x - y) * yy / y)
 }

src/net/torvald/parametricsky/Application.kt

@@ -12,16 +12,14 @@ import com.badlogic.gdx.graphics.g2d.SpriteBatch
 import net.torvald.unicode.EMDASH
 import net.torvald.colourutil.*
 import net.torvald.parametricsky.datasets.DatasetCIEXYZ
-import net.torvald.parametricsky.datasets.DatasetRGB
-import net.torvald.parametricsky.datasets.DatasetSpectral
 import net.torvald.terrarum.abs
+import net.torvald.terrarum.clut.Skybox
+import net.torvald.terrarum.clut.Skybox.coerceInSmoothly
+import net.torvald.terrarum.clut.Skybox.mapCircle
 import net.torvald.terrarum.inUse
 import net.torvald.terrarum.modulebasegame.worldgenerator.HALF_PI
-import net.torvald.terrarum.modulebasegame.worldgenerator.TWO_PI
 import java.awt.BorderLayout
 import java.awt.Dimension
-import java.awt.FlowLayout
-import java.awt.GridLayout
 import java.lang.Math.pow
 import javax.swing.*
 import kotlin.math.*
@@ -94,7 +92,16 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
         if (turbidity <= 0) throw IllegalStateException()
 
         // we need to use different model-state to accommodate different albedo for each spectral band but oh well...
-        genTexLoop(model)
+        genTexLoop(model, elevation)
+//        println("$elevation\t${ymaxDisp.text}\t${ymaxDisp2.text}")
+
+
+        /*for (elev in -75..75) {
+            val elevation = Math.toRadians(elev.toDouble())
+            val model = ArHosekSkyModel.arhosek_xyz_skymodelstate_alloc_init(turbidity, albedo, elevation.abs())
+            genTexLoop(model, elevation)
+            println("$elev\t${ymaxDisp.text}\t${ymaxDisp2.text}")
+        }*/
 
 
         val tex = Texture(oneScreen)
@@ -127,7 +134,7 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
     }
 
     val outTexWidth = 1
-    val outTexHeight = 256
+    val outTexHeight = 128
 
     private fun Float.scaleFun() =
             (1f - 1f / 2f.pow(this/6f)) * 0.97f
@@ -142,14 +149,20 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
             )
         }
         else {
-            val elevation1 = -Math.toDegrees(elevation)
-            val elevation2 = -Math.toDegrees(elevation) / 28.5
-            val scale = (1f - (1f - 1f / 1.8.pow(elevation1)) * 0.97f).toFloat()
-            val scale2 = (1.0 - (elevation2.pow(E) / E.pow(elevation2))*0.8).toFloat()
+            // maths model: https://www.desmos.com/calculator/cwi7iyzygg
+
+            val x = -Math.toDegrees(elevation).toFloat()
+//            val elevation2 = -Math.toDegrees(elevation) / 28.5
+            val p = 3.5f
+            val q = 7.5f
+            val s = -0.2f
+            val f = (1f - (1f - 1f / 1.8f.pow(x)) * 0.97f).toFloat()
+//            val g = (1.0 - (elevation2.pow(E) / E.pow(elevation2))*0.8).toFloat()
+            val h = ((x / q).pow(p) + 1f).pow(s)
             CIEXYZ(
-                this.X.scaleFun() * scale * scale2,
-                this.Y.scaleFun() * scale * scale2,
-                this.Z.scaleFun() * scale * scale2,
+                this.X.scaleFun() * f * h,
+                this.Y.scaleFun() * f * h,
+                this.Z.scaleFun() * f * h,
                 this.alpha
             )
         }
@@ -161,7 +174,7 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
      * Generated texture is as if you took the panorama picture of sky: up 70deg to horizon, east-south-west;
      * with sun not moving (sun is at exact south, sun's height is adjustable)
      */
-    private fun genTexLoop(state: ArHosekSkyModelState) {
+    private fun genTexLoop(state: ArHosekSkyModelState, elevation: Double) {
 
         fun normaliseY(y: Double): Float {
             var v = y.coerceAtLeast(0.0)
@@ -175,6 +188,7 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
         val ys2 = ArrayList<Float>()
 
         val halfHeight = oneScreen.height * 0.5
+        val elevationDeg = Math.toDegrees(elevation)
 
         for (x in 0 until oneScreen.width) {
             for (y in 0 until oneScreen.height) {
@@ -186,17 +200,19 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
                 val theta = sqrt(xf*xf + yf*yf) * HALF_PI*/
 
                 // AM-PM mapping (use with WIDTH=1)
-                var yf = (y * 2.0 / oneScreen.height) % 1.0
-                if (elevation < 0) yf *= 1.0 - pow(-elevation / HALF_PI, 0.333)
+                val yp = y % (oneScreen.height / 2)
+                val yi = yp - 3
+                val xf = -elevationDeg / 90.0
+                var yf = (yi / 58.0).coerceIn(0.0, 1.0).mapCircle().coerceInSmoothly(0.0, 0.95)
+                if (elevationDeg < 0) yf *= Skybox.superellipsoidDecay(1.0 / 3.0, xf)
+                val theta = yf * HALF_PI
                 val gamma = if (y < halfHeight) HALF_PI else 3 * HALF_PI
-                val theta = yf.mapCircle() * HALF_PI
-
 
 
                 val xyz = CIEXYZ(
                         ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, gamma, 0).toFloat(),
                         ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, gamma, 1).toFloat(),
-                        ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, gamma, 2).toFloat()
+                        ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, gamma, 2).toFloat(),
                 )
                 val xyz2 = xyz.scaleToFit(elevation)
                 ys.add(xyz.Y)
@@ -204,12 +220,12 @@ class Application(val WIDTH: Int, val HEIGHT: Int) : Game() {
                 val rgb = xyz2.toRGB().toColor()
                 rgb.a = 1f
 
-                val rgb2 = Color(
+                /*val rgb2 = Color(
                     ((rgb.r * 255f).roundToInt() xor 0xAA) / 255f,
                     ((rgb.g * 255f).roundToInt() xor 0xAA) / 255f,
                     ((rgb.b * 255f).roundToInt() xor 0xAA) / 255f,
                     rgb.a
-                )
+                )*/
 
                 oneScreen.setColor(rgb)
                 oneScreen.drawPixel(x, y)

src/net/torvald/terrarum/TerrarumAppConfiguration.kt

@@ -62,9 +62,10 @@ basegame
      * e.g. 0x02010034 will be translated as 2.1.52
      *
      */
-    const val VERSION_RAW: Long = 0x0000_000003_000002
+    const val VERSION_RAW: Long = 0x0000_000003_000003
     // Commit counts up to the Release 0.3.0: 2259
     // Commit counts up to the Release 0.3.1: 2278
+    // Commit counts up to the Release 0.3.2: 2732
 
     //////////////////////////////////////////////////////////
     //             CONFIGURATION FOR TILE MAKER             //

src/net/torvald/terrarum/TerrarumPostProcessor.kt

@@ -9,6 +9,7 @@ import com.badlogic.gdx.math.Matrix4
 import com.badlogic.gdx.utils.Disposable
 import com.jme3.math.FastMath
 import net.torvald.random.HQRNG
+import net.torvald.terrarum.App.IS_DEVELOPMENT_BUILD
 import net.torvald.terrarum.gamecontroller.KeyToggler
 import net.torvald.terrarum.ui.BasicDebugInfoWindow
 import net.torvald.terrarum.ui.Toolkit
@@ -150,9 +151,10 @@ object TerrarumPostProcessor : Disposable {
                 }
 
                 // draw dev build notifiers
-                if (App.IS_DEVELOPMENT_BUILD && Terrarum.ingame != null) {
+                // omitting this screws up HQ2X render for some reason
+                if (Terrarum.ingame != null) {
                     batch.inUse {
-                        batch.color = safeAreaCol
+                        batch.color = if (IS_DEVELOPMENT_BUILD) safeAreaCol else colourNull
                         App.fontGame.draw(it, thisIsDebugStr, 5f, App.scr.height - 24f)
                     }
                 }
@@ -192,6 +194,7 @@ object TerrarumPostProcessor : Disposable {
         return outFBO
     }
     private val rng = HQRNG()
+    private val colourNull = Color(0)
 
     private fun Double.format(digits: Int) = "%.${digits}f".format(this)
     private fun Float.format(digits: Int) = "%.${digits}f".format(this)

src/net/torvald/terrarum/clut/GenerateSkyboxTextureAtlas.kt

@@ -19,7 +19,7 @@ fun main() {
     // y: increasing turbidity (1.0 .. 10.0, in steps of 0.333)
     // x: elevations (-75 .. 75 in steps of 1, then albedo of [0.1, 0.3, 0.5, 0.7, 0.9])
     val texh = Skybox.gradSize * Skybox.turbCnt
-    val texw = Skybox.elevCnt * Skybox.albedoCnt
+    val texw = Skybox.elevCnt * Skybox.albedoCnt * 2
     val TGA_HEADER_SIZE = 18
 
     val bytes = ByteArray(TGA_HEADER_SIZE + texw * texh * 4 + 26)
@@ -44,47 +44,50 @@ fun main() {
     println("Generating texture atlas ($texw x $texh)...")
 
     // write pixels
-    for (albedo0 in 0 until Skybox.albedoCnt) {
-        val albedo = Skybox.albedos[albedo0]
-        println("Albedo=$albedo")
-        for (turb0 in 0 until Skybox.turbCnt) {
-            val turbidity = Skybox.turbiditiesD[turb0]
-            println("....... Turbidity=$turbidity")
-            for (elev0 in 0 until Skybox.elevCnt) {
-                val elevationDeg = Skybox.elevationsD[elev0]
-                val elevationRad = Math.toRadians(elevationDeg)
+    for (gammaPair in 0..1) {
+        for (albedo0 in 0 until Skybox.albedoCnt) {
+            val albedo = Skybox.albedos[albedo0]
+            println("Albedo=$albedo")
+            for (turb0 in 0 until Skybox.turbCnt) {
+                val turbidity = Skybox.turbiditiesD[turb0]
+                println("....... Turbidity=$turbidity")
+                for (elev0 in 0 until Skybox.elevCnt) {
+                    val elevationDeg = Skybox.elevationsD[elev0]
+                    val elevationRad = Math.toRadians(elevationDeg)
 //                println("... Elevation: $elevationDeg")
 
-                val state = ArHosekSkyModel.arhosek_xyz_skymodelstate_alloc_init(turbidity, albedo, elevationRad.abs())
+                    val state =
+                        ArHosekSkyModel.arhosek_xyz_skymodelstate_alloc_init(turbidity, albedo, elevationRad.abs())
 
-                for (yp in 0 until Skybox.gradSize) {
-                    val yi = yp - 3
-                    val xf = -elevationDeg / 90.0
-                    var yf = (yi / 58.0).coerceIn(0.0, 1.0).mapCircle().coerceInSmoothly(0.0, 0.95)
+                    for (yp in 0 until Skybox.gradSize) {
+                        val yi = yp - 10
+                        val xf = -elevationDeg / 90.0
+                        var yf = (yi / 58.0).coerceIn(0.0, 1.0).mapCircle().coerceInSmoothly(0.0, 0.95)
 
-                    // experiments visualisation: https://www.desmos.com/calculator/5crifaekwa
+                        // experiments visualisation: https://www.desmos.com/calculator/5crifaekwa
 //                    if (elevationDeg < 0) yf *= 1.0 - pow(xf, 0.333)
 //                    if (elevationDeg < 0) yf *= -2.0 * asin(xf - 1.0) / PI
-                    if (elevationDeg < 0) yf *= Skybox.superellipsoidDecay(1.0 / 3.0, xf)
-                    val theta = yf * HALF_PI
-                    // vertical angle, where 0 is zenith, ±90 is ground (which is odd)
+                        if (elevationDeg < 0) yf *= Skybox.superellipsoidDecay(1.0 / 3.0, xf)
+                        val theta = yf * HALF_PI
+                        // vertical angle, where 0 is zenith, ±90 is ground (which is odd)
 
 //                    println("$yp\t$theta")
 
-                    val xyz = CIEXYZ(
-                        ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, HALF_PI, 0).toFloat(),
-                        ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, HALF_PI, 1).toFloat(),
-                        ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, HALF_PI, 2).toFloat()
-                    )
-                    val xyz2 = xyz.scaleToFit(elevationDeg)
-                    val rgb = xyz2.toRGB().toColor()
-                    val colour = rgb.toIntBits().toLittle()
+                        val xyz = CIEXYZ(
+                            ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, (gammaPair * 2f + 1f) * HALF_PI, 0).toFloat(),
+                            ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, (gammaPair * 2f + 1f) * HALF_PI, 1).toFloat(),
+                            ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, (gammaPair * 2f + 1f) * HALF_PI, 2).toFloat()
+                        )
+                        val xyz2 = xyz.scaleToFit(elevationDeg)
+                        val rgb = xyz2.toRGB().toColor()
+                        val colour = rgb.toIntBits().toLittle()
 
-                    val imgOffX = (albedo0 * Skybox.elevCnt + elev0)
-                    val imgOffY = texh - 1 - (Skybox.gradSize * turb0 + yp)
-                    val fileOffset = TGA_HEADER_SIZE + 4 * (imgOffY * texw + imgOffX)
-                    for (i in 0..3) {
-                        bytes[fileOffset + i] = colour[bytesLut[i]]
+                        val imgOffX = albedo0 * Skybox.elevCnt + elev0 + Skybox.elevCnt * Skybox.albedoCnt * gammaPair
+                        val imgOffY = texh - 1 - (Skybox.gradSize * turb0 + yp)
+                        val fileOffset = TGA_HEADER_SIZE + 4 * (imgOffY * texw + imgOffX)
+                        for (i in 0..3) {
+                            bytes[fileOffset + i] = colour[bytesLut[i]]
+                        }
                     }
                 }
             }
@@ -93,7 +96,7 @@ fun main() {
 
     println("Atlas generation done!")
 
-    File("./assets/mods/basegame/weathers/main_skybox.tga").writeBytes(bytes)
+    File("./assets/clut/skybox.tga").writeBytes(bytes)
 }
 
 private val bytesLut = arrayOf(2,1,0,3,2,1,0,3) // For some reason BGRA order is what makes it work

src/net/torvald/terrarum/clut/Skybox.kt

@@ -13,6 +13,8 @@ import net.torvald.parametricsky.ArHosekSkyModel
 import net.torvald.terrarum.App
 import net.torvald.terrarum.App.printdbg
 import net.torvald.terrarum.abs
+import net.torvald.terrarum.floorToInt
+import net.torvald.terrarum.toInt
 import net.torvald.terrarumsansbitmap.gdx.TextureRegionPack
 import kotlin.math.*
 
@@ -25,7 +27,7 @@ object Skybox : Disposable {
     private const val PI = 3.141592653589793
     private const val TWO_PI = 6.283185307179586
 
-    const val gradSize = 64
+    const val gradSize = 78
 
     private lateinit var gradTexBinLowAlbedo: Array<TextureRegion>
     private lateinit var gradTexBinHighAlbedo: Array<TextureRegion>
@@ -37,6 +39,7 @@ object Skybox : Disposable {
     fun loadlut() {
         tex = Texture(Gdx.files.internal("assets/clut/skybox.png"))
         tex.setFilter(Texture.TextureFilter.Linear, Texture.TextureFilter.Linear)
+        tex.setWrap(Texture.TextureWrap.Repeat, Texture.TextureWrap.Repeat)
         texRegions = TextureRegionPack(tex, 2, gradSize - 2, 0, 2, 0, 1)
         texStripRegions = TextureRegionPack(tex, elevCnt, gradSize - 2, 0, 2, 0, 1)
     }
@@ -50,28 +53,67 @@ object Skybox : Disposable {
     }*/
 
     // use external LUT
-    operator fun get(elevationDeg: Double, turbidity: Double, albedo: Double): TextureRegion {
-        val elev = elevationDeg.coerceIn(-elevMax, elevMax).roundToInt().plus(elevMax).roundToInt()
-        val turb = turbidity.coerceIn(1.0, 10.0).minus(1.0).times(turbDivisor).roundToInt()
-        val alb = albedo.coerceIn(0.1, 0.9).minus(0.1).times(turbDivisor).roundToInt()
-        //printdbg(this, "elev $elevationDeg->$elev; turb $turbidity->$turb; alb $albedo->$alb")
-        return texRegions.get(alb * elevCnt + elev, turb)
+    operator fun get(elevationDeg: Double, turbidity: Double, albedo: Double, isAfternoon: Boolean): TextureRegion {
+       TODO()
     }
 
-    fun getUV(elevationDeg: Double, turbidity: Double, albedo: Double): Pair<Texture, FloatArray> {
-        val turb = turbidity.coerceIn(1.0, 10.0).minus(1.0).times(turbDivisor).roundToInt()
-        val alb = albedo.coerceIn(0.1, 0.9).minus(0.1).times(turbDivisor).roundToInt()
-        val region = texStripRegions.get(alb, turb)
+    data class SkyboxRenderInfo(
+        val texture: Texture,
+        val uvs: FloatArray,
+        val turbidityPoint: Float,
+        val albedoPoint: Float,
+    )
 
-        val elev = elevationDeg.coerceIn(-elevMax, elevMax).plus(elevMax).div(elevations.last.toDouble()).div(albedoCnt).times((elevCnt - 1.0) / elevCnt)
+    fun getUV(elevationDeg: Double, turbidity: Double, albedo: Double): SkyboxRenderInfo {
+        val turb = turbidity.coerceIn(turbiditiesD.first(), turbiditiesD.last()).minus(1.0).times(turbDivisor)
+        val turbLo = turb.floorToInt()
+        val turbHi = min(turbCnt - 1, turbLo + 1)
+        val alb = albedo.coerceIn(albedos.first(), albedos.last()).times(5.0)
+        val albLo = alb.floorToInt()
+        val albHi = min(albedoCnt - 1, albLo + 1)
+        val elev = elevationDeg.coerceIn(-elevMax, elevMax).plus(elevMax).div(elevations.last.toDouble()).div(albedoCnt * 2).times((elevCnt - 1.0) / elevCnt)
 
-        val u = region.u + (0.5f / tex.width) + elev.toFloat() // because of the nature of bilinear interpolation, half pixels from the edges must be discarded
+        // A: morn, turbLow, albLow
+        // B: noon, turbLow, albLow
+        // C: morn, turbHigh, albLow
+        // D: noon, turbHigh, albLow
+        // E: morn, turbLow, albHigh
+        // F: noon, turbLow, albHigh
+        // G: morn, turbHigh, albHigh
+        // H: noon, turbHigh, albHigh
 
-        return tex to floatArrayOf(
-            u,
-            region.v,
-            u,
-            region.v2
+        val regionA = texStripRegions.get(albLo + albedoCnt * 0, turbLo)
+        val regionB = texStripRegions.get(albLo + albedoCnt * 1, turbLo)
+        val regionC = texStripRegions.get(albLo + albedoCnt * 0, turbHi)
+        val regionD = texStripRegions.get(albLo + albedoCnt * 1, turbHi)
+        val regionE = texStripRegions.get(albHi + albedoCnt * 0, turbLo)
+        val regionF = texStripRegions.get(albHi + albedoCnt * 1, turbLo)
+        val regionG = texStripRegions.get(albHi + albedoCnt * 0, turbHi)
+        val regionH = texStripRegions.get(albHi + albedoCnt * 1, turbHi)
+        // (0.5f / tex.width): because of the nature of bilinear interpolation, half pixels from the edges must be discarded
+        val uA = regionA.u + (0.5f / tex.width) + elev.toFloat()
+        val uB = regionB.u + (0.5f / tex.width) + elev.toFloat()
+        val uC = regionC.u + (0.5f / tex.width) + elev.toFloat()
+        val uD = regionD.u + (0.5f / tex.width) + elev.toFloat()
+        val uE = regionE.u + (0.5f / tex.width) + elev.toFloat()
+        val uF = regionF.u + (0.5f / tex.width) + elev.toFloat()
+        val uG = regionG.u + (0.5f / tex.width) + elev.toFloat()
+        val uH = regionH.u + (0.5f / tex.width) + elev.toFloat()
+
+        return SkyboxRenderInfo(
+            tex,
+            floatArrayOf(
+                uA, regionA.v, uA, regionA.v2,
+                uB, regionB.v, uB, regionB.v2,
+                uC, regionC.v, uC, regionC.v2,
+                uD, regionD.v, uD, regionD.v2,
+                uE, regionE.v, uE, regionE.v2,
+                uF, regionF.v, uF, regionF.v2,
+                uG, regionG.v, uG, regionG.v2,
+                uH, regionH.v, uH, regionH.v2,
+            ),
+            (turb - turbLo).toFloat(),
+            (alb - albLo).toFloat(),
         )
     }
 
@@ -88,15 +130,20 @@ object Skybox : Disposable {
             )
         }
         else {
-            val deg1 = (-elevationDeg / elevMax).pow(0.93).times(-elevMax)
-            val elevation1 = -deg1
-            val elevation2 = -deg1 / 28.5
-            val scale = (1f - (1f - 1f / 1.8.pow(elevation1)) * 0.97f).toFloat()
-            val scale2 = (1.0 - (elevation2.pow(E) / E.pow(elevation2))*0.8).toFloat()
+            // maths model: https://www.desmos.com/calculator/cwi7iyzygg
+
+            val x = -elevationDeg.toFloat()
+//            val elevation2 = elevationDeg.toFloat() / 28.5f
+            val p = 3.5f
+            val q = 7.5f
+            val s = -0.2f
+            val f = (1f - (1f - 1f / 1.8f.pow(x)) * 0.97f).toFloat()
+//            val g = (1.0 - (elevation2.pow(E) / E.pow(elevation2))*0.8).toFloat()
+            val h = ((x / q).pow(p) + 1f).pow(s)
             CIEXYZ(
-                this.X.scaleFun() * scale * scale2,
-                this.Y.scaleFun() * scale * scale2,
-                this.Z.scaleFun() * scale * scale2,
+                this.X.scaleFun() * f * h,
+                this.Y.scaleFun() * f * h,
+                this.Z.scaleFun() * f * h,
                 this.alpha
             )
         }
@@ -105,15 +152,13 @@ object Skybox : Disposable {
     val elevations = (0..150)
     val elevMax = elevations.last / 2.0
     val elevationsD = elevations.map { -elevMax + it } // -75, -74, -73, ..., 74, 75 // (specifically using whole number of angles because angle units any finer than 1.0 would make "hack" sunsut happen too fast)
-    val turbidities = (0..45) // 1, 1.2, 1.4, 1.6, ..., 10.0
+    val turbidities = (0..25) // 1, 1.2, 1.4, 1.6, ..., 6.0
     val turbDivisor = 5.0
     val turbiditiesD = turbidities.map { 1.0 + it / turbDivisor }
-    val albedos = arrayOf(0.1, 0.3, 0.5, 0.7, 0.9)
+    val albedos = arrayOf(0.0, 0.2, 0.4, 0.6, 0.8, 1.0)
     val elevCnt = elevations.count()
     val turbCnt = turbidities.count()
     val albedoCnt = albedos.size
-    val albedoLow = 0.1
-    val albedoHight = 0.8 // for theoretical "winter wonderland"?
     val gamma = HALF_PI
 
     internal fun Double.mapCircle() = sin(HALF_PI * this)
@@ -121,8 +166,7 @@ object Skybox : Disposable {
     internal fun initiate() {
         printdbg(this, "Initialising skybox model")
 
-        gradTexBinLowAlbedo = getTexturmaps(albedoLow)
-        gradTexBinHighAlbedo = getTexturmaps(albedoHight)
+        TODO()
 
         App.disposables.add(this)
 
@@ -198,7 +242,7 @@ object Skybox : Disposable {
 //            printdbg(this, "elev $elevationDeg turb $turbidity")
 
             for (yp in 0 until gradSize) {
-                val yi = yp - 3
+                val yi = yp - 10
                 val xf = -elevationDeg / 90.0
                 var yf = (yi / 58.0).coerceIn(0.0, 1.0).mapCircle().coerceInSmoothly(0.0, 0.95)
 

src/net/torvald/terrarum/weather/WeatherMixer.kt

@@ -154,7 +154,7 @@ internal object WeatherMixer : RNGConsumer {
 
     }
 
-    var turbidity = 4.0; private set
+    var turbidity = 1.0; private set
     private var gH = 1.4f * App.scr.height
 //    private var gH = 0.8f * App.scr.height
 
@@ -168,9 +168,11 @@ internal object WeatherMixer : RNGConsumer {
         drawSkybox(camera, batch, world)
     }
 
+    private val parallaxDomainSize = 400f
+    private val turbidityDomainSize = 533.3333f
+
     private fun drawSkybox(camera: Camera, batch: FlippingSpriteBatch, world: GameWorld) {
         val parallaxZeroPos = (world.height / 3f)
-        val parallaxDomainSize = 300f
 
         // we will not care for nextSkybox for now
         val timeNow = (forceTimeAt ?: world.worldTime.TIME_T.toInt()) % WorldTime.DAY_LENGTH
@@ -199,17 +201,20 @@ internal object WeatherMixer : RNGConsumer {
          -+ <- 0.0  =
          */
         val parallax = ((parallaxZeroPos - WorldCamera.gdxCamY.div(TILE_SIZEF)) / parallaxDomainSize).times(-1f).coerceIn(-1f, 1f)
+        val turbidityCoeff = ((parallaxZeroPos - WorldCamera.gdxCamY.div(TILE_SIZEF)) / turbidityDomainSize).times(-1f).coerceIn(-1f, 1f)
         parallaxPos = parallax
 //        println(parallax) // parallax value works as intended.
 
         gdxBlendNormalStraightAlpha()
 
+        turbidity = (3.5 + turbidityCoeff * 2.5).coerceIn(1.0, 6.0)
         val thisTurbidity = forceTurbidity ?: turbidity
 
-        // TODO trilinear with (deg, turb, alb)
         val gradY = -(gH - App.scr.height) * ((parallax + 1f) / 2f)
-        val (tex, uvs) = Skybox.getUV(solarElev, thisTurbidity, 0.3)
 
+        val (tex, uvs, turbX, albX) = Skybox.getUV(solarElev, thisTurbidity, 0.3)
+
+        val mornNoonBlend = (1f/4000f * (timeNow - 43200) + 0.5f).coerceIn(0f, 1f) // 0.0 at T41200; 0.5 at T43200; 1.0 at T45200;
 
         starmapTex.texture.bind(1)
         Gdx.gl.glActiveTexture(GL20.GL_TEXTURE0) // so that batch that comes next will bind any tex to it
@@ -220,20 +225,26 @@ internal object WeatherMixer : RNGConsumer {
         batch.inUse {
             batch.shader = shaderBlendMax
             shaderBlendMax.setUniformi("tex1", 1)
-            shaderBlendMax.setUniformf("drawOffset", 0f, gradY)
-            shaderBlendMax.setUniformf("drawOffsetSize", App.scr.wf, gH)
-            shaderBlendMax.setUniform2fv("skyboxUV1", uvs, 0, 2)
-            shaderBlendMax.setUniform2fv("skyboxUV2", uvs, 2, 2)
+            shaderBlendMax.setUniformf("drawOffsetSize", 0f, gradY, App.scr.wf, gH)
+            shaderBlendMax.setUniform4fv("uvA", uvs, 0, 4)
+            shaderBlendMax.setUniform4fv("uvB", uvs, 4, 4)
+            shaderBlendMax.setUniform4fv("uvC", uvs, 8, 4)
+            shaderBlendMax.setUniform4fv("uvD", uvs, 12, 4)
+            shaderBlendMax.setUniform4fv("uvE", uvs, 16, 4)
+            shaderBlendMax.setUniform4fv("uvF", uvs, 20, 4)
+            shaderBlendMax.setUniform4fv("uvG", uvs, 24, 4)
+            shaderBlendMax.setUniform4fv("uvH", uvs, 28, 4)
+            shaderBlendMax.setUniformf("texBlend", mornNoonBlend, turbX, albX, 0f)
             shaderBlendMax.setUniformf("astrumScroll", astrumOffX + astrumX, astrumOffY + astrumY)
             shaderBlendMax.setUniformf("randomNumber",
 //                (world.worldTime.TIME_T.plus(31L) xor 1453L + 31L).and(1023).toFloat(),
 //                (world.worldTime.TIME_T.plus(37L) xor  862L + 31L).and(1023).toFloat(),
 //                (world.worldTime.TIME_T.plus(23L) xor 1639L + 29L).and(1023).toFloat(),
 //                (world.worldTime.TIME_T.plus(29L) xor 2971L + 41L).and(1023).toFloat(),
-                world.worldTime.TIME_T.div(+12.1f).plus(31L),
-                world.worldTime.TIME_T.div(-11.8f).plus(37L),
-                world.worldTime.TIME_T.div(+11.9f).plus(23L),
-                world.worldTime.TIME_T.div(-12.3f).plus(29L),
+                world.worldTime.TIME_T.div(+14.1f).plus(31L),
+                world.worldTime.TIME_T.div(-13.8f).plus(37L),
+                world.worldTime.TIME_T.div(+13.9f).plus(23L),
+                world.worldTime.TIME_T.div(-14.3f).plus(29L),
             )
 
             batch.color = Color.WHITE

src/shaders/blendSkyboxStars.frag

@@ -13,10 +13,16 @@ out vec4 fragColor;
 
 const vec2 boolean = vec2(0.0, 1.0);
 
-uniform vec2 drawOffset; // value of the 'gradY'
-uniform vec2 drawOffsetSize; // value of the 'gradH'
-uniform vec2 skyboxUV1; // (u, v) for the skybox drawing
-uniform vec2 skyboxUV2; // (u2, v2) for the skybox drawing
+uniform vec4 drawOffsetSize; // (gradX, gradY, gradW, gradH)
+uniform vec4 uvA; // (u, v, u2, v2) for morn, turbLow, albLow
+uniform vec4 uvB; // (u, v, u2, v2) for noon, turbLow, albLow
+uniform vec4 uvC; // (u, v, u2, v2) for morn, turbHigh, albLow
+uniform vec4 uvD; // (u, v, u2, v2) for noon, turbHigh, albLow
+uniform vec4 uvE; // (u, v, u2, v2) for morn, turbLow, albHigh
+uniform vec4 uvF; // (u, v, u2, v2) for noon, turbLow, albHigh
+uniform vec4 uvG; // (u, v, u2, v2) for morn, turbHigh, albHigh
+uniform vec4 uvH; // (u, v, u2, v2) for noon, turbHigh, albHigh
+uniform vec4 texBlend; // (morn/noon, turbidity, albedo, unused)
 uniform vec2 tex1Size = vec2(4096.0);
 uniform vec2 astrumScroll = vec2(0.0);
 uniform vec4 randomNumber = vec4(1.0, -2.0, 3.0, -4.0);
@@ -112,15 +118,36 @@ vec4 random(vec2 p) {
 
 // draw call to this function must use UV coord of (0,0,1,1)!
 void main(void) {
-    vec2 skyboxTexCoord = mix(skyboxUV1, skyboxUV2, v_texCoords);
-    vec2 astrumTexCoord = (v_texCoords * drawOffsetSize + drawOffset + astrumScroll) / tex1Size;
+    vec4 colorTexA = texture(u_texture, mix(uvA.xy, uvA.zw, v_texCoords));
+    vec4 colorTexB = texture(u_texture, mix(uvB.xy, uvB.zw, v_texCoords));
+    vec4 colorTexC = texture(u_texture, mix(uvC.xy, uvC.zw, v_texCoords));
+    vec4 colorTexD = texture(u_texture, mix(uvD.xy, uvD.zw, v_texCoords));
+    vec4 colorTexE = texture(u_texture, mix(uvE.xy, uvE.zw, v_texCoords));
+    vec4 colorTexF = texture(u_texture, mix(uvF.xy, uvF.zw, v_texCoords));
+    vec4 colorTexG = texture(u_texture, mix(uvG.xy, uvG.zw, v_texCoords));
+    vec4 colorTexH = texture(u_texture, mix(uvH.xy, uvH.zw, v_texCoords));
 
+
+    vec2 astrumTexCoord = (v_texCoords * drawOffsetSize.zw + drawOffsetSize.xy + astrumScroll) / tex1Size;
     vec4 randomness = snoise4((gl_FragCoord.xy - astrumScroll) * 0.16) * 2.0; // multiply by 2 so that the "density" of the stars would be same as the non-random version
 
 
-    vec4 colorTex0 = texture(u_texture, skyboxTexCoord);
     vec4 colorTex1 = texture(tex1, astrumTexCoord) * randomness;
 
+    // notations used: https://en.wikipedia.org/wiki/File:Enclosing_points.svg and https://en.wikipedia.org/wiki/File:3D_interpolation2.svg
+    vec4 colorTex0 = mix(
+        mix(
+            mix(colorTexA, colorTexE, texBlend.z), // c00 = c000..c100
+            mix(colorTexC, colorTexG, texBlend.z), // c10 = c010..c110
+            texBlend.y
+        ), // c0 = c00..c10
+        mix(
+            mix(colorTexB, colorTexF, texBlend.z), // c01 = c001..c101
+            mix(colorTexD, colorTexH, texBlend.z), // c11 = c011..c111
+            texBlend.y
+        ), // c1 = c01..c11
+        texBlend.x
+    ); // c = c0..c1
 
 
     fragColor = (max(colorTex0, colorTex1) * boolean.yyyx) + boolean.xxxy;