find free space (rectangle) in bitmap (LibGDX Pixmap)

package ru.serdjuk.retro.game.palette.v3

import com.badlogic.gdx.graphics.Color
import com.badlogic.gdx.graphics.Pixmap
import com.badlogic.gdx.graphics.Texture
import com.badlogic.gdx.graphics.g2d.TextureRegion
import com.badlogic.gdx.math.MathUtils
import com.badlogic.gdx.math.Rectangle
import com.badlogic.gdx.math.Vector2

class Bitmap(width: Int, height: Int, format: Pixmap.Format) : Pixmap(width, height, format) {

    private val errorMessage = "No more space in pixmap."
    val atlas = HashMap<String, TextureRegion>()

    fun insertRectangle(color: Color, fill: Boolean, area: Pair<Int, Int>) {
        val position = getFreePosition(area.first, area.second, color.toIntBits())
        if (position != null) {
            if (fill) fillRectangle(position.x.toInt(), position.y.toInt(), area.first, area.second)
            drawRectangle(position.x.toInt(), position.y.toInt(), area.first, area.second)
        } else error(errorMessage)
    }

    fun insertRectangleNamed(name: String, color: Color, fill: Boolean, area: Pair<Int, Int>, texture: Texture) {
        val position = getFreePosition(area.first, area.second, color.toIntBits())
        if (position != null) {
            if (fill) fillRectangle(position.x.toInt(), position.y.toInt(), area.first, area.second)
            drawRectangle(position.x.toInt(), position.y.toInt(), area.first, area.second)
            atlas[name] = TextureRegion(texture, position.x.toInt(), position.y.toInt(), area.first, area.second)
        } else error(errorMessage)
    }


    fun insertAreas(color: Color, fill: Boolean, vararg areas: Pair<Int, Int>) {
        areas.forEachIndexed { index, area ->
            insertRectangle(color, fill, area)
        }
    }

    /*
    insertColoredAres (width,height,Color)
     */
    fun insertColorAres(fill: Boolean, vararg coloredAreas: Triple<Int, Int, Color>) {
        coloredAreas.forEach {
            insertRectangle(it.third, fill, Pair(it.first, it.second))
        }
    }

    fun insert(pixmap: Pixmap) {
        val position = getFreePosition(pixmap.width, pixmap.height)
        if (position != null) {
            drawPixmap(pixmap, position.x.toInt(), position.y.toInt())
        } else error(errorMessage)
    }

    /*
    pixmap  new pixmap well need added
    name - name for atlas
    texture - this. pixmap texture
     */
    fun insertNamed(pixmap: Pixmap, name: String, texture: Texture) {
        val position = getFreePosition(pixmap.width, pixmap.height)
        if (position != null) {
            drawPixmap(pixmap, position.x.toInt(), position.y.toInt())
            atlas[name] = TextureRegion(texture, position.x.toInt(), position.y.toInt(), pixmap.width, pixmap.height)
        } else error(errorMessage)
    }


    fun getFreePosition(soughtWidth: Int, soughtHeight: Int, clearPixelColor: Int = 0): Vector2? {
        val position = Vector2()
        while (true) {
            var fit = true
            var h = 0
            getClearPixel(position, clearPixelColor, soughtWidth)
            val x = position.x
            val y = position.y
            while (h++ != soughtHeight) {
                if (position.y > (height - soughtHeight)) return null

                repeat(soughtWidth) w@{
                    if (getPixel((position.x + it).toInt(), position.y.toInt()) != clearPixelColor) {
                        fit = false
                        position.x += it + 1
                        return@w
                    }
                }
                if (!fit) {
                    position.y = y
                    break
                } else {
                    position.y++
                }
            }
            if (fit) {
                position.set(x, y)
                break
            }
        }
        return position
    }


    private fun getClearPixel(position: Vector2, clearPixel: Int, soughtWidth: Int): Vector2 {
        while (getPixel(position.x.toInt(), position.y.toInt()) != clearPixel) {
            if (++position.x >= (width - soughtWidth)) {
                position.x = 0f
                position.y++
            }
        }
        return position
    }


}