From 5da4e186644bfeb5d129de47bb77e8a6f05f6ddc Mon Sep 17 00:00:00 2001
From: Seth Hillbrand <hillbrand@ucdavis.edu>
Date: Thu, 7 Feb 2019 21:26:27 -0800
Subject: [PATCH] bitmaps: Handle mask colors

Some transparent bitmaps use masking colors to show the binary
opaque/transparent.

Fixes: lp:1814893
* https://bugs.launchpad.net/kicad/+bug/1814893
---
 common/gal/cairo/cairo_gal.cpp   | 7 ++++++-
 common/gal/opengl/opengl_gal.cpp | 5 ++++-
 eeschema/sch_bitmap.cpp          | 2 +-
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/common/gal/cairo/cairo_gal.cpp b/common/gal/cairo/cairo_gal.cpp
index d198c9c53c..1f5871c6e6 100644
--- a/common/gal/cairo/cairo_gal.cpp
+++ b/common/gal/cairo/cairo_gal.cpp
@@ -300,6 +300,9 @@ void CAIRO_GAL_BASE::DrawBitmap( const BITMAP_BASE& aBitmap )
     unsigned char* pix_buffer = cairo_image_surface_get_data( image );
     // The pixel buffer of the initial bitmap:
     auto bm_pix_buffer = (( BITMAP_BASE&)aBitmap).GetImageData();
+    uint32_t mask_color = ( bm_pix_buffer->GetMaskRed() << 16 )+
+            ( bm_pix_buffer->GetMaskGreen() << 8 ) +
+            ( bm_pix_buffer->GetMaskBlue() );
 
     // Copy the source bitmap to the cairo bitmap buffer.
     // In cairo bitmap buffer, a ARGB32 bitmap is an ARGB pixel packed into a uint_32
@@ -315,8 +318,10 @@ void CAIRO_GAL_BASE::DrawBitmap( const BITMAP_BASE& aBitmap )
 
             if( bm_pix_buffer->HasAlpha() )
                 pixel += bm_pix_buffer->GetAlpha( col, row ) << 24;
+            else if( bm_pix_buffer->HasMask() && pixel == mask_color )
+                pixel += ( wxALPHA_TRANSPARENT << 24 );
             else
-                pixel += ( 0xff << 24 );
+                pixel += ( wxALPHA_OPAQUE << 24 );
 
             // Write the pixel to the cairo image buffer:
             uint32_t* pix_ptr = (uint32_t*) pix_buffer;
diff --git a/common/gal/opengl/opengl_gal.cpp b/common/gal/opengl/opengl_gal.cpp
index e8b41b8023..e3703bd6d0 100644
--- a/common/gal/opengl/opengl_gal.cpp
+++ b/common/gal/opengl/opengl_gal.cpp
@@ -158,8 +158,11 @@ GLuint GL_BITMAP_CACHE::cacheBitmap( const BITMAP_BASE* aBitmap )
 
             if( imgData->HasAlpha() )
                 p[3] = imgData->GetAlpha( x, y );
+            else if( imgData->HasMask() && p[0] == imgData->GetMaskRed() &&
+                     p[1] == imgData->GetMaskGreen() && p[2] == imgData->GetMaskBlue() )
+                p[3] = wxALPHA_TRANSPARENT;
             else
-                p[3] = 255;
+                p[3] = wxALPHA_OPAQUE;
         }
     }
 
diff --git a/eeschema/sch_bitmap.cpp b/eeschema/sch_bitmap.cpp
index e8af80ec6d..6bdc9fe122 100644
--- a/eeschema/sch_bitmap.cpp
+++ b/eeschema/sch_bitmap.cpp
@@ -234,5 +234,5 @@ BITMAP_DEF SCH_BITMAP::GetMenuImage() const
 void SCH_BITMAP::ViewGetLayers( int aLayers[], int& aCount ) const
 {
     aCount = 1;
-    aLayers[0] = LAYER_WORKSHEET;
+    aLayers[0] = LAYER_DRAW_BITMAPS;
 }