api: Improve lerp JD, inputs TextColor -> RGBLike

KyoriPowered · Jun 7, 2021 · 6805744 · 6805744
1 parent f519a33
commit 6805744
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Showing 2 changed files with 12 additions and 9 deletions.
diff --git a/api/src/main/java/net/kyori/adventure/text/format/TextColor.java b/api/src/main/java/net/kyori/adventure/text/format/TextColor.java
@@ -237,23 +237,26 @@ public interface TextColor extends Comparable<TextColor>, Examinable, RGBLike, S
   /**
    * Linearly interpolates between {@code a} and {@code b} by {@code t}.
    *
-   * @param t the interpolation value, between {@code 0.0} and {@code 1.0}
-   * @param a the lower bound
-   * @param b the upper bound
-   * @return the interpolated value
+   * <p>This returns a color blended between color {@code a}, at {@code t=0.0}, and color {@code b}, at {@code t=1.0}.</p>
+   *
+   * @param t the interpolation value, between {@code 0.0} and {@code 1.0} (both inclusive)
+   * @param a the lower bound ({@code t=0.0})
+   * @param b the upper bound ({@code t=1.0})
+   * @return the interpolated value, a color between the two input colors {@code a} and {@code b}
    * @since 4.8.0
    */
-  static @NonNull TextColor lerp(final float t, final @NonNull TextColor a, final @NonNull TextColor b) {
+  static @NotNull TextColor lerp(final float t, final @NotNull RGBLike a, final @NotNull RGBLike b) {
+    final float clampedT = Math.min(1.0f, Math.max(0.0f, t)); // clamp between 0 and 1
     final int ar = a.red();
     final int br = b.red();
     final int ag = a.green();
     final int bg = b.green();
     final int ab = a.blue();
     final int bb = b.blue();
     return color(
-      Math.round(ar + t * (br - ar)),
-      Math.round(ag + t * (bg - ag)),
-      Math.round(ab + t * (bb - ab))
+      Math.round(ar + clampedT * (br - ar)),
+      Math.round(ag + clampedT * (bg - ag)),
+      Math.round(ab + clampedT * (bb - ab))
     );
   }
 

diff --git a/api/src/test/java/net/kyori/adventure/text/format/TextColorTest.java b/api/src/test/java/net/kyori/adventure/text/format/TextColorTest.java
@@ -103,7 +103,7 @@ void testLerp() {
   }
 
   @Test
-  public void testEquality() {
+  void testEquality() {
     new EqualsTester()
       .addEqualityGroup(
         TextColor.color(0xff0000),