improve empty code point rendering

Reported-By: turtius

src/integration-test/kotlin/de/bixilon/minosoft/gui/rendering/font/renderer/component/ChatComponentRendererTest.kt

@@ -65,7 +65,12 @@ class ChatComponentRendererTest {
 
     fun emptyChar() {
         val info = render(TextComponent("a")) // a has a length of 0px
-        info.assert(lineIndex = 0, lines = emptyList(), size = Vec2())
+        info.assert(lineIndex = 0, lines = listOf(LineRenderInfo(BaseComponent())), size = Vec2())
+    }
+
+    fun `empty char and then char`() {
+        val info = render(TextComponent("ab")) // a has a length of 0px
+        info.assert(lineIndex = 0, lines = listOf(LineRenderInfo(BaseComponent("b"), width = 0.5f)), size = Vec2(0.5f, 11f))
     }
 
     fun singleChar() {
@@ -475,5 +480,32 @@ class ChatComponentRendererTest {
         ))
     }
 
+    fun `render empty chars and newline`() {
+        val consumer = DummyComponentConsumer()
+        val text = TextComponent("aaaa\naaaa")
+
+        val info = render(text, fontManager = FontManager(consumer.Font()), consumer = consumer)
+        info.assert(lineIndex = 1, size = Vec2(0.0f, 11.0f), lines = listOf(
+            LineRenderInfo(BaseComponent(), 0.0f),
+            LineRenderInfo(BaseComponent(), 0.0f),
+        ))
+        consumer.assert(*arrayOf<DummyComponentConsumer.RendererdCodePoint>())
+    }
+
+    fun `render empty chars mixed and newline`() {
+        val text = TextComponent("abaaa\naaaba")
+        val consumer = DummyComponentConsumer()
+
+        val info = render(text, fontManager = FontManager(consumer.Font()), consumer = consumer)
+        info.assert(lineIndex = 1, size = Vec2(0.5f, 22.0f), lines = listOf(
+            LineRenderInfo(BaseComponent("b"), 0.5f),
+            LineRenderInfo(BaseComponent("b"), 0.5f),
+        ))
+        consumer.assert(
+            DummyComponentConsumer.RendererdCodePoint(Vec2(10, 10)),
+            DummyComponentConsumer.RendererdCodePoint(Vec2(10, 21)),
+        )
+    }
+
     // TODO: shadow, formatting (italic; strikethrough; underlined)
 }

src/main/java/de/bixilon/minosoft/gui/rendering/font/renderer/code/CodePointRenderer.kt

@@ -71,7 +71,7 @@ interface CodePointRenderer {
         if (consumer != null) {
             render(offset.offset, properties, color, properties.shadow, FormattingCodes.BOLD in formatting, FormattingCodes.ITALIC in formatting, properties.scale, consumer, options)
         } else {
-            info.update(offset, properties, width, spacing) // info should only be updated when we determinate text properties, we know all that already when actually rendering it        }
+            info.update(offset, properties, width, spacing, false) // info should only be updated when we determinate text properties, we know all that already when actually rendering it        }
         }
         offset.offset.x += width
 

src/main/java/de/bixilon/minosoft/gui/rendering/font/renderer/component/TextComponentRenderer.kt

@@ -80,8 +80,9 @@ object TextComponentRenderer : ChatComponentRenderer<TextComponent> {
 
 
     private fun LineRenderInfo.pushAndRender(offset: Vec2, text: TextComponent, line: StringBuilder, width: Float, color: RGBColor, properties: TextRenderProperties, consumer: GUIVertexConsumer?, options: GUIVertexOptions?) {
-        push(text, line)
+        if (consumer == null) {
-        if (consumer != null) {
+            push(text, line)
+        } else {
             renderFormatting(offset, text, width, color, properties, consumer, options)
         }
     }
@@ -102,6 +103,7 @@ object TextComponentRenderer : ChatComponentRenderer<TextComponent> {
         var skipWhitespaces = false
 
         val line = StringBuilder()
+        var update = false
         var filled = false
         val lineStart = Vec2(offset.offset)
 
@@ -119,6 +121,7 @@ object TextComponentRenderer : ChatComponentRenderer<TextComponent> {
                 }
                 lineStart(offset.offset)
                 skipWhitespaces = true
+                update = false
                 if (filled) break else continue
             }
             if (skipWhitespaces && Character.isWhitespace(codePoint)) {
@@ -127,12 +130,14 @@ object TextComponentRenderer : ChatComponentRenderer<TextComponent> {
 
             val renderer = getRenderer(codePoint, properties, textFont, fontManager)
             if (renderer != null && renderer.calculateWidth(properties.scale, properties.shadow) <= 0.0f) {
+                update = true
                 continue
             }
             skipWhitespaces = false
             if (renderer == null) {
                 continue
             }
+            update = false
 
             val lineIndex = info.lineIndex
 
@@ -159,6 +164,9 @@ object TextComponentRenderer : ChatComponentRenderer<TextComponent> {
             line.appendCodePoint(codePoint)
         }
 
+        if (update && consumer == null) {
+            info.update(offset, properties, 0.0f, 0.0f, true)
+        }
         if (line.isNotEmpty()) {
             info.lines[info.lineIndex].pushAndRender(lineStart, text, line, offset.offset.x - lineStart.x, color, properties, consumer, options)
         }

src/main/java/de/bixilon/minosoft/gui/rendering/font/renderer/element/TextRenderInfo.kt

@@ -26,7 +26,7 @@ class TextRenderInfo(
     var cutOff = false
 
 
-    fun update(offset: TextOffset, properties: TextRenderProperties, width: Float, spacing: Float): LineRenderInfo {
+    fun update(offset: TextOffset, properties: TextRenderProperties, width: Float, spacing: Float, empty: Boolean): LineRenderInfo {
         size.x = maxOf(offset.offset.x - offset.initial.x + width, size.x)
 
         val line: LineRenderInfo
@@ -34,7 +34,9 @@ class TextRenderInfo(
             // first char of all lines
             line = LineRenderInfo()
             lines += line
-            size.y += properties.lineHeight
+            if (!empty) {
+                size.y += properties.lineHeight
+            }
         } else {
             line = lines[lineIndex]
         }