curioustorvald/Terrarum
1
0
Fork 0
mirror of https://github.com/curioustorvald/Terrarum.git synced 2026-06-10 18:44:05 +09:00
Code Issues Packages Projects Releases Wiki Activity

skybox atlas texture generation

Browse Source
This commit is contained in:
minjaesong
2023-08-01 16:50:37 +09:00
parent 0c00b3b7cc
commit 451808cd1c
13 changed files with 218 additions and 93 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
src/net/torvald/terrarum/modulebasegame/TitleScreen.kt
View File

@@ -241,7 +241,8 @@ class TitleScreen(batch: FlippingSpriteBatch) : IngameInstance(batch) {
uiContainer.add(uiRemoCon)
CommandDict // invoke
Skybox // invoke
Skybox.loadlut() // invoke
// Skybox.initiate() // invoke the lengthy calculation
// TODO add console here

102
src/net/torvald/terrarum/modulebasegame/clut/GenerateSkyboxTextureAtlas.kt Normal file
View File

@@ -0,0 +1,102 @@
package net.torvald.terrarum.modulebasegame.clut
import net.torvald.colourutil.CIEXYZ
import net.torvald.colourutil.toColor
import net.torvald.colourutil.toRGB
import net.torvald.parametricsky.ArHosekSkyModel
import net.torvald.terrarum.abs
import net.torvald.terrarum.modulebasegame.clut.Skybox.coerceInSmoothly
import net.torvald.terrarum.modulebasegame.clut.Skybox.mapCircle
import net.torvald.terrarum.modulebasegame.clut.Skybox.scaleToFit
import net.torvald.terrarum.modulebasegame.worldgenerator.HALF_PI
import net.torvald.terrarum.serialise.toLittle
import java.io.File
import kotlin.math.PI
import kotlin.math.pow
import kotlin.math.roundToInt
/**
* Created by minjaesong on 2023-08-01.
*/
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 = 2 * Skybox.elevCnt * 5
val TGA_HEADER_SIZE = 18
val bytes = ByteArray(TGA_HEADER_SIZE + texw * texh * 4 + 26)
// write header
byteArrayOf(
0, // ID field
0, // colour map (none)
2, // colour type (unmapped RGB)
0,0,0,0,0, // colour map spec (empty)
0,0, // x origin (0)
0,0, // y origin (0)
(texw and 255).toByte(),(texw.ushr(8) and 255).toByte(), // width
(texh and 255).toByte(),(texh.ushr(8) and 255).toByte(), // height
32, // bits-per-pixel (8bpp RGBA)
8 // image descriptor
).forEachIndexed { i,b -> bytes[i] = b }
// write footer
"\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000TRUEVISION-XFILE\u002E\u0000".forEachIndexed { i, c -> bytes[18 + texw * texh * 4 + i] =
c.code.toByte()
}
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)
// println("... Elevation: $elevationDeg")
val state = ArHosekSkyModel.arhosek_xyz_skymodelstate_alloc_init(turbidity, albedo, elevationRad.abs())
for (yp in 0 until Skybox.gradSize) {
val yi = yp - 3
val xf = -elevationDeg / 90.0
var yf = (yi / 58.0).coerceIn(0.0, 1.0).mapCircle().coerceInSmoothly(0.0, 0.95)
// experiments visualisation: https://www.desmos.com/calculator/5crifaekwa
// if (elevationDeg < 0) yf *= 1.0 - pow(xf, 0.333)
// if (elevationDeg < 0) yf *= -2.0 * asin(xf - 1.0) / PI
if (elevationDeg < 0) yf *= Skybox.superellipsoidDecay(1.0 / 3.0, xf)
val theta = yf * HALF_PI
// vertical angle, where 0 is zenith, ±90 is ground (which is odd)
// println("$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 imgOffX = 2 * (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..7) {
bytes[fileOffset + i] = colour[bytesLut[i]]
}
}
}
}
}
println("Atlas generation done!")
File("./assets/mods/basegame/weathers/main_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

100
src/net/torvald/terrarum/modulebasegame/clut/Skybox.kt
View File

@@ -2,6 +2,7 @@ package net.torvald.terrarum.modulebasegame.clut
import com.badlogic.gdx.graphics.Pixmap
import com.badlogic.gdx.graphics.Texture
import com.badlogic.gdx.graphics.g2d.TextureRegion
import com.badlogic.gdx.utils.Disposable
import com.jme3.math.FastMath
import net.torvald.colourutil.CIEXYZ
@@ -10,8 +11,10 @@ import net.torvald.colourutil.toRGB
import net.torvald.parametricsky.ArHosekSkyModel
import net.torvald.terrarum.App
import net.torvald.terrarum.App.printdbg
import net.torvald.terrarum.ModMgr
import net.torvald.terrarum.abs
import net.torvald.terrarum.modulebasegame.worldgenerator.HALF_PI
import net.torvald.terrarumsansbitmap.gdx.TextureRegionPack
import kotlin.math.*
/**
@@ -21,29 +24,39 @@ object Skybox : Disposable {
const val gradSize = 64
private val gradTexBinLowAlbedo: Array<Texture>
private val gradTexBinHighAlbedo: Array<Texture>
private lateinit var gradTexBinLowAlbedo: Array<TextureRegion>
private lateinit var gradTexBinHighAlbedo: Array<TextureRegion>
operator fun get(elevationDeg: Double, turbidity: Double, highAlbedo: Boolean = false): Texture {
// if (elevationDeg !in elevationsD) {
// throw IllegalArgumentException("Elevation not in ±75° (got $elevationDeg)")
// }
// if (turbidity !in turbiditiesD) {
// throw IllegalArgumentException("Turbidity not in 1..10 (got $turbidity)")
// }
private lateinit var tex: Texture
private lateinit var texRegions: TextureRegionPack
val elev = elevationDeg.coerceIn(elevationsD).toInt() - elevations.first
val turb = ((turbidity.coerceIn(turbiditiesD) - turbiditiesD.start) / (turbidities.step / 10.0)).toInt()
fun loadlut() {
tex = Texture(ModMgr.getGdxFile("basegame", "weathers/main_skybox.png"))
tex.setFilter(Texture.TextureFilter.Linear, Texture.TextureFilter.Linear)
texRegions = TextureRegionPack(tex, 2, gradSize - 2, 0, 2, 0, 1)
}
// printdbg(this, "$elevationDeg $turbidity ; $elev $turb")
// use internal LUT
/*operator fun get(elevationDeg: Double, turbidity: Double, albedo: Double): TextureRegion {
val elev = elevationDeg.coerceIn(-75.0, 75.0).times(2.0).roundToInt().plus(150)
val turb = turbidity.coerceIn(1.0, 10.0).minus(1.0).times(3.0).roundToInt()
val alb = albedo.coerceIn(0.1, 0.9).minus(0.1).times(5.0).roundToInt()
return gradTexBinLowAlbedo[elev * turbCnt + turb]
}*/
return (if (highAlbedo) gradTexBinHighAlbedo else gradTexBinLowAlbedo)[elev * turbCnt + turb]
// use external LUT
operator fun get(elevationDeg: Double, turbidity: Double, albedo: Double): TextureRegion {
val elev = elevationDeg.coerceIn(-75.0, 75.0).roundToInt().plus(75)
val turb = turbidity.coerceIn(1.0, 10.0).minus(1.0).times(3.0).roundToInt()
val alb = albedo.coerceIn(0.1, 0.9).minus(0.1).times(5.0).roundToInt()
//printdbg(this, "elev $elevationDeg->$elev; turb $turbidity->$turb; alb $albedo->$alb")
return texRegions.get(alb * elevCnt + elev, turb)
}
private fun Float.scaleFun() =
(1f - 1f / 2f.pow(this/6f)) * 0.97f
private fun CIEXYZ.scaleToFit(elevationDeg: Double): CIEXYZ {
internal fun CIEXYZ.scaleToFit(elevationDeg: Double): CIEXYZ {
return if (elevationDeg >= 0) {
CIEXYZ(
this.X.scaleFun(),
@@ -67,20 +80,21 @@ object Skybox : Disposable {
}
}
private val elevations = (-75..75) //zw 151
private val elevationsD = (elevations.first.toDouble() .. elevations.last.toDouble())
private val turbidityStep = 5
private val turbidities = (1_0..10_0 step turbidityStep) // (100 / turbidityStep) - 1
private val turbiditiesD = (turbidities.first / 10.0..turbidities.last / 10.0)
private val elevCnt = elevations.count()
private val turbCnt = turbidities.count()
private val albedoLow = 0.1
private val albedoHight = 0.8 // for theoretical "winter wonderland"?
private val gamma = HALF_PI
val elevations = (0..150) //
val elevationsD = elevations.map { -75.0 + 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..27) // 1, 1.333, 1.666, 2, 2,333, ... , 10.0
val turbiditiesD = turbidities.map { 1.0 + it / 3.0 }
val albedos = arrayOf(0.1, 0.3, 0.5, 0.7, 0.9)
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
private fun Double.mapCircle() = sin(HALF_PI * this)
internal fun Double.mapCircle() = sin(HALF_PI * this)
init {
internal fun initiate() {
printdbg(this, "Initialising skybox model")
gradTexBinLowAlbedo = getTexturmaps(albedoLow)
@@ -97,7 +111,7 @@ object Skybox : Disposable {
* @param q polynomial degree. 2+. Larger value means sharper transition around the point p
* @param x the 'x' value of the function, as in `y=f(x)`. 0.0..1.0
*/
private fun polynomialDecay(p: Double, q: Int, x: Double): Double {
internal fun polynomialDecay(p: Double, q: Int, x: Double): Double {
val sign = if (q % 2 == 1) -1 else 1
val a1 = -1.0 / p
val a2 = 1.0 / (1.0 - p)
@@ -108,7 +122,7 @@ object Skybox : Disposable {
sign * a2.pow(q - 1.0) * (x - 1.0).pow(q)
}
private fun polynomialDecay2(p: Double, q: Int, x: Double): Double {
internal fun polynomialDecay2(p: Double, q: Int, x: Double): Double {
val sign = if (q % 2 == 1) 1 else -1
val a1 = -1.0 / p
val a2 = 1.0 / (1.0 - p)
@@ -119,11 +133,11 @@ object Skybox : Disposable {
sign * a2.pow(q - 1.0) * (x - 1.0).pow(q) + 1.0
}
private fun superellipsoidDecay(p: Double, x: Double): Double {
internal fun superellipsoidDecay(p: Double, x: Double): Double {
return 1.0 - (1.0 - (1.0 - x).pow(1.0 / p)).pow(p)
}
private fun Double.coerceInSmoothly(low: Double, high: Double): Double {
internal fun Double.coerceInSmoothly(low: Double, high: Double): Double {
val x = this.coerceIn(low, high)
val x2 = ((x - low) * (high - low).pow(-1.0))
// return FastMath.interpolateLinear(polynomialDecay2(0.5, 2, x2), low, high)
@@ -133,25 +147,26 @@ object Skybox : Disposable {
/**
* To get the idea what the fuck is going on here, please refer to https://www.desmos.com/calculator/snqglcu2wl
*/
private fun smoothLinear(p: Double, x0: Double): Double {
internal fun smoothLinear(p: Double, x0: Double): Double {
val x = x0 - 0.5
val t = 0.5 * sqrt(1.0 - 2.0 * p)
val p1 = sqrt(1.0 - 2.0 * p)
val t = 0.5 * p1
val y0 = if (x < -t)
(1.0 / p) * (x + 0.5).pow(2) - 0.5
else if (x > t)
-(1.0 / p) * (x - 0.5).pow(2) + 0.5
else
x * 2.0 / (1.0 + sqrt(1.0 - 2.0 * p))
x * 2.0 / (1.0 + p1)
return y0 + 0.5
}
private fun getTexturmaps(albedo: Double): Array<Texture> {
private fun getTexturmaps(albedo: Double): Array<TextureRegion> {
return Array(elevCnt * turbCnt) {
val elevationDeg = (it / turbCnt).plus(elevations.first).toDouble()
val elevationDeg = elevationsD[it / turbCnt]
val elevationRad = Math.toRadians(elevationDeg)
val turbidity = 1.0 + (it % turbCnt) / (10.0 / turbidityStep)
val turbidity = turbiditiesD[it % turbCnt]
val state = ArHosekSkyModel.arhosek_xyz_skymodelstate_alloc_init(turbidity, albedo, elevationRad.abs())
val pixmap = Pixmap(1, gradSize, Pixmap.Format.RGBA8888)
@@ -161,15 +176,17 @@ object Skybox : Disposable {
for (yp in 0 until gradSize) {
val yi = yp - 3
val xf = -elevationDeg / 90.0
var yf = (yi / 58.0).coerceInSmoothly(0.0, 0.95)
var yf = (yi / 58.0).coerceIn(0.0, 1.0).mapCircle().coerceInSmoothly(0.0, 0.95)
// 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 *= superellipsoidDecay(1.0 / 3.0, xf)
val theta = (yf.mapCircle() * HALF_PI)
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, gamma, 0).toFloat(),
ArHosekSkyModel.arhosek_tristim_skymodel_radiance(state, theta, gamma, 1).toFloat(),
@@ -187,12 +204,13 @@ object Skybox : Disposable {
it.setFilter(Texture.TextureFilter.Linear, Texture.TextureFilter.Linear)
}
pixmap.dispose()
texture
TextureRegion(texture)
}
}
override fun dispose() {
gradTexBinLowAlbedo.forEach { it.dispose() }
gradTexBinHighAlbedo.forEach { it.dispose() }
if (::gradTexBinLowAlbedo.isInitialized) gradTexBinLowAlbedo.forEach { it.texture.dispose() }
if (::gradTexBinHighAlbedo.isInitialized) gradTexBinHighAlbedo.forEach { it.texture.dispose() }
if (::tex.isInitialized) tex.dispose()
}
}