Remove height functor for shadows and replace with plane equation params

Change-Id: I948eceb2c58dc50468993dba54c209f18e440e48
Reviewed-on: https://skia-review.googlesource.com/15873
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>

1 files changed, 54 insertions, 18 deletions

diff --git a/include/utils/SkShadowUtils.h b/include/utils/SkShadowUtils.h
index 01514a46ff..4a497bb397 100644
--- a/include/utils/SkShadowUtils.h
+++ b/include/utils/SkShadowUtils.h
@@ -43,29 +43,65 @@ public:
                            uint32_t flags = SkShadowFlags::kNone_ShadowFlag,
                            SkResourceCache* cache = nullptr);
 
-   /**
-    * Draw an offset spot shadow and outlining ambient shadow for the given path using a disc
-    * light. Takes a function to vary the z value based on the transformed x and y position.
-    * This shadow will not be cached, as the assumption is that this will be used for animation.
-    *
-    * @param canvas  The canvas on which to draw the shadows.
-    * @param path  The occluder used to generate the shadows.
-    * @param heightFunc  A function which returns the vertical offset of the occluder from the
-    *  canvas based on local x and y values (the current matrix is not applied).
-    * @param lightPos  The 3D position of the light relative to the canvas plane. This is
-    *  independent of the canvas's current matrix.
-    * @param lightRadius  The radius of the disc light.
-    * @param ambientAlpha  The maximum alpha of the ambient shadow.
-    * @param spotAlpha  The maxium alpha of the spot shadow.
-    * @param color  The shadow color.
-    * @param flags  Options controlling opaque occluder optimizations and shadow appearance. See
-    *               SkShadowFlags.
-    */
+    /**
+     * Draw an offset spot shadow and outlining ambient shadow for the given path using a disc
+     * light. Takes a function to vary the z value based on the local x and y position.
+     * This shadow will not be cached, as the assumption is that this will be used for animation.
+     *
+     * Deprecated version with height functor (to be removed when Android is updated).
+     *
+     * @param canvas  The canvas on which to draw the shadows.
+     * @param path  The occluder used to generate the shadows.
+     * @param heightFunc  A function which returns the vertical offset of the occluder from the
+     *  canvas based on local x and y values (the current matrix is not applied).
+     * @param lightPos  The 3D position of the light relative to the canvas plane. This is
+     *  independent of the canvas's current matrix.
+     * @param lightRadius  The radius of the disc light.
+     * @param ambientAlpha  The maximum alpha of the ambient shadow.
+     * @param spotAlpha  The maxium alpha of the spot shadow.
+     * @param color  The shadow color.
+     * @param flags  Options controlling opaque occluder optimizations and shadow appearance. See
+     *               SkShadowFlags.
+     */
     static void DrawUncachedShadow(SkCanvas* canvas, const SkPath& path,
                                    std::function<SkScalar(SkScalar, SkScalar)> heightFunc,
                                    const SkPoint3& lightPos, SkScalar lightRadius,
                                    SkScalar ambientAlpha, SkScalar spotAlpha, SkColor color,
+                                   uint32_t flags = SkShadowFlags::kNone_ShadowFlag) {
+        SkPoint3 zPlane;
+        zPlane.fZ = heightFunc(0, 0);
+        zPlane.fX = heightFunc(1, 0) - zPlane.fZ;
+        zPlane.fY = heightFunc(0, 1) - zPlane.fZ;
+
+        DrawUncachedShadow(canvas, path, zPlane, lightPos, lightRadius, ambientAlpha, spotAlpha,
+                           color, flags);
+    }
+
+    /**
+     * Draw an offset spot shadow and outlining ambient shadow for the given path using a disc
+     * light. Uses a plane function to vary the z value based on the local x and y position.
+     * This shadow will not be cached, as the assumption is that this will be used for animation.
+     *
+     * @param canvas  The canvas on which to draw the shadows.
+     * @param path  The occluder used to generate the shadows.
+     * @param zPlaneParams  Values for the plane function which returns the Z offset of the
+     *  occluder from the canvas based on local x and y values (the current matrix is not applied).
+     * @param lightPos  The 3D position of the light relative to the canvas plane. This is
+     *  independent of the canvas's current matrix.
+     * @param lightRadius  The radius of the disc light.
+     * @param ambientAlpha  The maximum alpha of the ambient shadow.
+     * @param spotAlpha  The maxium alpha of the spot shadow.
+     * @param color  The shadow color.
+     * @param flags  Options controlling opaque occluder optimizations and shadow appearance. See
+     *               SkShadowFlags.
+     */
+    static void DrawUncachedShadow(SkCanvas* canvas, const SkPath& path,
+                                   const SkPoint3& zPlaneParams,
+                                   const SkPoint3& lightPos, SkScalar lightRadius,
+                                   SkScalar ambientAlpha, SkScalar spotAlpha, SkColor color,
                                    uint32_t flags = SkShadowFlags::kNone_ShadowFlag);
+
+
 };
 
 #endif