Signal-Android/core-util/src/main/java/org/signal/core/util/FontUtil.kt

40 wiersze
1.2 KiB
Kotlin

package org.signal.core.util
import android.graphics.Bitmap
import android.graphics.Canvas
import android.graphics.Color
import android.graphics.Paint
import android.graphics.PorterDuff
import kotlin.math.abs
object FontUtil {
private const val SAMPLE_EMOJI = "\uD83C\uDF0D" // 🌍
/**
* Certain platforms cannot render emoji above a certain font size.
*
* This will attempt to render an emoji at the specified font size and tell you if it's possible.
* It does this by rendering an emoji into a 1x1 bitmap and seeing if the resulting pixel is non-transparent.
*
* https://stackoverflow.com/a/50988748
*/
@JvmStatic
fun canRenderEmojiAtFontSize(size: Float): Boolean {
val bitmap: Bitmap = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888)
val canvas = Canvas(bitmap)
val paint = Paint()
paint.textSize = size
paint.textAlign = Paint.Align.CENTER
val ascent: Float = abs(paint.ascent())
val descent: Float = abs(paint.descent())
val halfHeight = (ascent + descent) / 2.0f
canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR)
canvas.drawText(SAMPLE_EMOJI, 0.5f, 0.5f + halfHeight - descent, paint)
return bitmap.getPixel(0, 0) != 0
}
}