[skottie] Animation::animationTick() -> Animation::seek()

Replace poorly defined animationTick() with a normalized seek() method.

TBR=
Change-Id: Id2ea17bb426fe86fede0d6c8a3d93236902f10af
Reviewed-on: https://skia-review.googlesource.com/130508
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>

1 files changed, 21 insertions, 3 deletions

diff --git a/modules/skottie/include/Skottie.h b/modules/skottie/include/Skottie.h
index 0a89ca0438..906ea82b68 100644
--- a/modules/skottie/include/Skottie.h
+++ b/modules/skottie/include/Skottie.h
@@ -48,9 +48,27 @@ public:
 
     ~Animation() override;
 
-    void render(SkCanvas*, const SkRect* dst = nullptr) const;
-
-    void animationTick(SkMSec);
+    /**
+     * Draws the current animation frame.
+     *
+     * @param canvas   destination canvas
+     * @param dst      optional destination rect
+     */
+    void render(SkCanvas* canvas, const SkRect* dst = nullptr) const;
+
+    /**
+     * Updates the animation state for |t|.
+     *
+     * @param t   normalized [0..1] frame selector, where 0 == inPoint and 1 == outPoint.
+     */
+    void seek(SkScalar t);
+
+    /**
+     * Returns the animation duration in seconds.
+     */
+    SkScalar duration() const {
+        return (fOutPoint - fInPoint) / fFrameRate;
+    }
 
     const SkString& version() const { return fVersion;   }
     const SkSize&      size() const { return fSize;      }