Transform vertices for distance field glyphs on CPU.

This allows batching of DF draws with different view matrices.

For perspective matrices this means the transformed position vertex
attribute must have w values. Currently, non-perspective DF draws still
use 2 component positions, though this could be changed in the future.
Consequently, perspective draws can batch with other perspective draws
but not non-perspective draws.

Adds a GM to test batching and reusing the same blobs with both perspective
and non-perspective matrices.

Change-Id: I0e42c5449ebf3a5a54025dbcdec824d904d5bd9e
Reviewed-on: https://skia-review.googlesource.com/79900
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/gn/gm.gni b/gn/gm.gni
index 4d4833f6bb..62be999944 100644
--- a/gn/gm.gni
+++ b/gn/gm.gni
@@ -101,6 +101,7 @@ gm_sources = [
   "$_gm/dashing.cpp",
   "$_gm/degeneratesegments.cpp",
   "$_gm/dftext.cpp",
+  "$_gm/dftext_blob_persp.cpp",
   "$_gm/discard.cpp",
   "$_gm/displacement.cpp",
   "$_gm/distantclip.cpp",