Index: chrome/android/java/src/org/chromium/chrome/browser/util/MathUtils.java |
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/util/MathUtils.java b/chrome/android/java/src/org/chromium/chrome/browser/util/MathUtils.java |
index 01c116d576afe7d7cc16d3aae030c7bdc70f3804..81501d3830d2e930d968095f85d3b0113bb31da9 100644 |
--- a/chrome/android/java/src/org/chromium/chrome/browser/util/MathUtils.java |
+++ b/chrome/android/java/src/org/chromium/chrome/browser/util/MathUtils.java |
@@ -73,4 +73,71 @@ public class MathUtils { |
int mod = a % b; |
return mod >= 0 ? mod : mod + b; |
} |
+ |
+ /** |
+ * Moves {@code value} forward to {@code target} based on {@code speed}. |
+ * @param value The current value. |
+ * @param target The target value. |
+ * @param speed How far to move {@code value} to {@code target}. 0 doesn't move it at all. 1 |
+ * moves it to {@code target}. |
+ * @return The new interpolated value. |
+ */ |
+ public static float interpolate(float value, float target, float speed) { |
+ return (value + (target - value) * speed); |
+ } |
+ |
+ /** |
+ * Smooth a value between 0 and 1. |
+ * @param t The value to smooth. |
+ * @return The smoothed value between 0 and 1. |
+ */ |
+ public static float smoothstep(float t) { |
+ return t * t * (3.0f - 2.0f * t); |
+ } |
+ |
+ /** |
+ * Scales the provided dimension such that it is just large enough to fit |
+ * the target width and height. |
+ * |
+ * @param dimensions The dimensions to scale |
+ * @param targetWidth The target width |
+ * @param targetHeight The target height |
+ * @return The scale factor applied to dimensions |
+ */ |
+ public static float scaleToFitTargetSize( |
+ int [] dimensions, int targetWidth, int targetHeight) { |
+ if (dimensions.length < 2 || dimensions[0] <= 0 || dimensions[1] <= 0) { |
+ throw new IllegalArgumentException( |
+ "Expected dimensions to have length >= 2 && dimensions[0] > 0 && " |
+ + "dimensions[1] > 0"); |
+ } |
+ float scale = Math.max( |
+ (float) targetWidth / dimensions[0], |
+ (float) targetHeight / dimensions[1]); |
+ dimensions[0] *= scale; |
+ dimensions[1] *= scale; |
+ return scale; |
+ } |
+ |
+ /** |
+ * Flips {@code value} iff {@code flipSign} is {@code true}. |
+ * @param value The value to flip. |
+ * @param flipSign Whether or not to flip the value. |
+ * @return {@code value} iff {@code flipSign} is {@code false}, otherwise negative |
+ * {@code value}. |
+ */ |
+ public static int flipSignIf(int value, boolean flipSign) { |
+ return flipSign ? -value : value; |
+ } |
+ |
+ /** |
+ * Flips {@code value} iff {@code flipSign} is {@code true}. |
+ * @param value The value to flip. |
+ * @param flipSign Whether or not to flip the value. |
+ * @return {@code value} iff {@code flipSign} is {@code false}, otherwise negative |
+ * {@code value}. |
+ */ |
+ public static float flipSignIf(float value, boolean flipSign) { |
+ return flipSign ? -value : value; |
+ } |
} |