Optimize rendering of 2D barcodes: create Rect only on black regions.

This is a ~2x improvement in rendering time, taking my example
down from ~390ms per barcode to ~190ms.

Bug: 872907
Change-Id: Iecddc30edf92ad943765d4382b332e00d493c320
Reviewed-on: https://pdfium-review.googlesource.com/40533
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/fxbarcode/BC_TwoDimWriter.cpp b/fxbarcode/BC_TwoDimWriter.cpp
index 6852fee35c..09f39c2443 100644
--- a/fxbarcode/BC_TwoDimWriter.cpp
+++ b/fxbarcode/BC_TwoDimWriter.cpp
@@ -42,11 +42,11 @@ void CBC_TwoDimWriter::RenderDeviceResult(CFX_RenderDevice* device,
   }
   for (int32_t x = 0; x < m_output->GetWidth(); x++) {
     for (int32_t y = 0; y < m_output->GetHeight(); y++) {
-      CFX_PathData rect;
-      rect.AppendRect((float)leftPos + x, (float)topPos + y,
-                      (float)(leftPos + x + 1), (float)(topPos + y + 1));
       if (m_output->Get(x, y)) {
         CFX_GraphStateData data;
+        CFX_PathData rect;
+        rect.AppendRect((float)leftPos + x, (float)topPos + y,
+                        (float)(leftPos + x + 1), (float)(topPos + y + 1));
         device->DrawPath(&rect, &matri, &data, m_barColor, 0, FXFILL_WINDING);
       }
     }