Dynamic ProgressComponent text color (#1123)

* progress text color

* applied requested changes

* only apply tint if the bar is taking the whole text space

* applied suggested changes

2 files changed, 51 insertions, 3 deletions

diff --git a/src/main/java/de/hysky/skyblocker/skyblock/tabhud/widget/component/ProgressComponent.java b/src/main/java/de/hysky/skyblocker/skyblock/tabhud/widget/component/ProgressComponent.java
index ae6d64c4..3f5f3443 100644
--- a/src/main/java/de/hysky/skyblocker/skyblock/tabhud/widget/component/ProgressComponent.java
+++ b/src/main/java/de/hysky/skyblocker/skyblock/tabhud/widget/component/ProgressComponent.java
@@ -1,6 +1,7 @@
 package de.hysky.skyblocker.skyblock.tabhud.widget.component;
 
 import de.hysky.skyblocker.skyblock.tabhud.util.Ico;
+import de.hysky.skyblocker.utils.ColorUtils;
 import net.minecraft.client.gui.DrawContext;
 import net.minecraft.item.ItemStack;
 import net.minecraft.text.Text;
@@ -23,6 +24,7 @@ public class ProgressComponent extends Component {
 	private final Text desc, bar;
 	private final float pcnt;
 	private final int color;
+	private final boolean colorIsBright;
 	private final int barW;
 
 	public ProgressComponent(ItemStack ico, Text d, Text b, float pcnt, int color) {
@@ -43,6 +45,7 @@ public class ProgressComponent extends Component {
 		this.barW = BAR_WIDTH;
 		this.width = ICO_DIM + PAD_L + Math.max(this.barW, txtRend.getWidth(this.desc));
 		this.height = txtRend.fontHeight + PAD_S + 2 + txtRend.fontHeight + 2;
+		this.colorIsBright = ColorUtils.isBright(this.color);
 	}
 
 	public ProgressComponent(ItemStack ico, Text text, float pcnt, int color) {
@@ -62,8 +65,12 @@ public class ProgressComponent extends Component {
 		int barY = y + txtRend.fontHeight + PAD_S;
 		int endOffsX = ((int) (this.barW * (this.pcnt / 100f)));
 		context.fill(barX + endOffsX, barY, barX + this.barW, barY + BAR_HEIGHT, COL_BG_BAR);
-		context.fill(barX, barY, barX + endOffsX, barY + BAR_HEIGHT,
-				this.color);
-		context.drawTextWithShadow(txtRend, bar, barX + 3, barY + 2, 0xffffffff);
+		context.fill(barX, barY, barX + endOffsX, barY + BAR_HEIGHT, this.color);
+
+		int textWidth = txtRend.getWidth(bar);
+		// Only turn text dark when it is wider than the filled bar and the filled bar is bright.
+		// The + 4 is because the text is indented 3 pixels and 1 extra pixel to the right as buffer.
+		boolean textDark = endOffsX >= textWidth + 4 && this.colorIsBright;
+		context.drawText(txtRend, bar, barX + 3, barY + 2, textDark ? 0xff000000 : 0xffffffff, !textDark);
 	}
 }
diff --git a/src/main/java/de/hysky/skyblocker/utils/ColorUtils.java b/src/main/java/de/hysky/skyblocker/utils/ColorUtils.java
index 1babe5e5..a9ea6a9f 100644
--- a/src/main/java/de/hysky/skyblocker/utils/ColorUtils.java
+++ b/src/main/java/de/hysky/skyblocker/utils/ColorUtils.java
@@ -54,4 +54,45 @@ public class ColorUtils {
 
 		return (r3 << 16) | (g3 << 8 ) | b3;
 	}
+
+	/**
+	 * Checks if the specified color is bright or dark.
+	 */
+	public static boolean isBright(int color) {
+		float[] components = getFloatComponents(color);
+
+		float red = components[0];
+		float green = components[1];
+		float blue = components[2];
+
+		double luminance = luminance(red, green, blue);
+		double whiteContrast = contrastRatio(luminance, 1.0);
+		double blackContrast = contrastRatio(luminance, 0.0);
+		return whiteContrast < blackContrast;
+	}
+
+	/**
+	 * Returns the luminance value of the color.
+	 *
+	 * @link <a href="https://stackoverflow.com/questions/596216/formula-to-determine-perceived-brightness-of-rgb-color/56678483#56678483">Stackoverflow explanation</a>
+	 */
+	private static double luminance(float red, float green, float blue) {
+		double r = (red <= 0.04045F) ? red / 12.92F : Math.pow((red + 0.055F) / 1.055F, 2.4F);
+		double g = (green <= 0.04045F) ? green / 12.92F : Math.pow((green + 0.055F) / 1.055F, 2.4F);
+		double b = (blue <= 0.04045F) ? blue / 12.92F : Math.pow((blue + 0.055F) / 1.055F, 2.4F);
+
+		return Math.fma(0.2126, r, Math.fma(0.7152, g, 0.0722 * b));
+	}
+
+	/**
+	 * Checks the contrast ratio between two luminance values.
+	 */
+	private static double contrastRatio(double background, double content) {
+		double brightest = Math.max(background, content);
+		double darkest = Math.min(background, content);
+
+		return (brightest + 0.05) / (darkest + 0.05);
+	}
+
+
 }