commit 94fda947ebebad2d1533162e8b218957c8ec7c90
author Jim Van Verth <jvanverth@google.com> Thu Jul 15 16:24:17 2021 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Fri Jul 16 16:49:52 2021 +0000
tree 010f27b924157759f4500bc79ef23c51731a2f3f
parent 126002c27dfa294be4d9fb8e24f301537fab5bd6

Reland "Fix directional shadows."

This is a reland of 6789b824015373104bc3282c971e435a9f542f59

Original change's description:
> Fix directional shadows.
>
> The xy offset calculation for drawShadow was not quite correct. Rather
> than normalizing the light vector and using the xy values of that as the
> base offset value, we should scale the light vector by 1/z.
>
> See https://github.com/flutter/engine/pull/27124#issuecomment-880182653
> for more detail.
>
> Bug: skia:10781
> Change-Id: Ib69a313cb96a532f8d89644e3d69f666a184e897
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/428880
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Jim Van Verth <jvanverth@google.com>

Bug: skia:10781
Change-Id: Ib58d374aa03d0144512e5ded6ccd572c74783607
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/428978
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>

src/utils/SkShadowUtils.cpp

diff --git a/src/utils/SkShadowUtils.cpp b/src/utils/SkShadowUtils.cpp
index 5a32ec4..f433821 100644
--- a/src/utils/SkShadowUtils.cpp
+++ b/src/utils/SkShadowUtils.cpp
@@ -664,9 +664,7 @@
 
     SkPoint3 zPlaneParams = rec.fZPlaneParams;
     SkPoint3 devLightPos = rec.fLightPos;
-    if (directional) {
-        devLightPos.normalize();
-    } else {
+    if (!directional) {
         viewMatrix.mapPoints((SkPoint*)&devLightPos.fX, 1);
     }
     float lightRadius = rec.fLightRadius;