Skip to content

Dont apply underline until text stream is complete #52

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
bjdodson-openai merged 1 commit into from
Jan 28, 2026
Merged

Dont apply underline until text stream is complete #52

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
58 changes: 42 additions & 16 deletions richtext-ui/src/commonMain/kotlin/com/halilibo/richtext/ui/string/Text.kt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -130,6 +130,20 @@ public fun RichTextScope.Text(
)
}
}
val animatedResult = if (renderOptions.animate && inlineContents.isEmpty()) {
rememberAnimatedTextResult(
annotated = decoratedTextResult.annotatedString,
contentColor = contentColor,
renderOptions = renderOptions,
isLeafText = isLeafText,
sharedAnimationState = sharedAnimationState,
)
} else {
null
}
val animatedText = animatedResult?.text ?: decoratedTextResult.annotatedString
val underlineAlphaForOffset = animatedResult?.alphaForOffset

val underlineModifier = if (underlineSpecs.isNotEmpty()) {
Modifier.drawWithContent {
drawContent()
Expand All @@ -141,25 +155,14 @@ public fun RichTextScope.Text(
end = spec.range.end,
underlineStyle = spec.range.underlineStyle,
color = spec.color,
alphaForOffset = underlineAlphaForOffset,
)
}
}
} else {
Modifier
}

val animatedText = if (renderOptions.animate && inlineContents.isEmpty()) {
rememberAnimatedText(
annotated = decoratedTextResult.annotatedString,
contentColor = contentColor,
renderOptions = renderOptions,
isLeafText = isLeafText,
sharedAnimationState = sharedAnimationState,
)
} else {
decoratedTextResult.annotatedString
}

if (inlineContents.isEmpty()) {
Text(
text = animatedText,
Expand Down Expand Up @@ -212,6 +215,7 @@ private fun androidx.compose.ui.graphics.drawscope.DrawScope.drawUnderline(
end: Int,
underlineStyle: UnderlineStyle,
color: Color,
alphaForOffset: ((Int) -> Float)?,
) {
val textLength = layoutResult.layoutInput.text.text.length
val clampedStart = start.coerceIn(0, textLength)
Expand Down Expand Up @@ -265,8 +269,10 @@ private fun androidx.compose.ui.graphics.drawscope.DrawScope.drawUnderline(
val xStart = startBox.left.roundToInt().toFloat()
val xEnd = endBox.right.roundToInt().toFloat()

val alpha = alphaForOffset?.invoke(segmentEnd - 1)?.coerceIn(0f, 1f) ?: 1f
if (alpha <= 0f) continue
drawLine(
color = color,
color = color.copy(alpha = color.alpha * alpha),
start = Offset(xStart, y),
end = Offset(xEnd, y),
strokeWidth = strokeWidthPx,
Expand Down Expand Up @@ -303,14 +309,19 @@ public class MarkdownAnimationState {
(lastAnimationStartMs - System.currentTimeMillis()).coerceAtLeast(0).toInt()
}

private data class AnimatedTextResult(
val text: AnnotatedString,
val alphaForOffset: (Int) -> Float,
)

@Composable
private fun rememberAnimatedText(
private fun rememberAnimatedTextResult(
annotated: AnnotatedString,
renderOptions: RichTextRenderOptions,
contentColor: Color,
sharedAnimationState: MarkdownAnimationState,
isLeafText: Boolean,
): AnnotatedString {
): AnimatedTextResult {
val coroutineScope = rememberCoroutineScope()
val animations = remember { mutableStateMapOf<Int, TextAnimation>() }
val textToRender = remember { mutableStateOf(AnnotatedString("")) }
Expand Down Expand Up @@ -372,7 +383,7 @@ private fun rememberAnimatedText(

// contentColor rarely changes, and it's not already a State. When contentColor changes, a new
// AnnotatedString must be created using the updated contentColor value.
return remember(contentColor) {
val text = remember(contentColor) {
// textToRender and the set of animations are tracked as States, and trigger the derivedStateOf
// to return a new value in order to create a new AnnotatedString with the latest text and
// animated Brushes.
Expand All @@ -389,6 +400,21 @@ private fun rememberAnimatedText(
)
}
}.value

return AnimatedTextResult(
text = text,
alphaForOffset = { offset ->
var bestStart = -1
var bestAlpha = 1f
animations.values.forEach { animation ->
if (animation.startIndex <= offset && animation.startIndex > bestStart) {
bestStart = animation.startIndex
bestAlpha = animation.alpha
}
}
bestAlpha
}
)
}

private class TextAnimation(val startIndex: Int) {
Expand Down