I/O script changes for GSoC 2017 Vertex Paint

These are changes to the ply and fbx export functions, and the ply
import function, to deal with vertex color alphas as implemented in the
GSoC 2017 Vertex Paint project - see T52910 & D2855

4 files changed, 14 insertions, 9 deletions

diff --git a/io_mesh_ply/export_ply.py b/io_mesh_ply/export_ply.py
index d4db5710..8de5d674 100644
--- a/io_mesh_ply/export_ply.py
+++ b/io_mesh_ply/export_ply.py
@@ -154,7 +154,8 @@ def save_mesh(filepath,
     if use_colors:
         fw("property uchar red\n"
            "property uchar green\n"
-           "property uchar blue\n")
+           "property uchar blue\n"
+           "property uchar alpha\n")
 
     fw("element face %d\n" % len(mesh.tessfaces))
     fw("property list uchar uint vertex_indices\n")
@@ -167,7 +168,7 @@ def save_mesh(filepath,
         if use_uv_coords:
             fw(" %.6f %.6f" % v[2])  # uv
         if use_colors:
-            fw(" %u %u %u" % v[3])  # col
+            fw(" %u %u %u %u" % v[3])  # col
         fw("\n")
 
     for pf in ply_faces:
diff --git a/io_mesh_ply/import_ply.py b/io_mesh_ply/import_ply.py
index eb097ba9..86fc2e1b 100644
--- a/io_mesh_ply/import_ply.py
+++ b/io_mesh_ply/import_ply.py
@@ -242,7 +242,7 @@ def load_ply_mesh(filepath, ply_name):
             uvindices = (el.index(b's'), el.index(b't'))
             if -1 in uvindices:
                 uvindices = None
-            colindices = el.index(b'red'), el.index(b'green'), el.index(b'blue')
+            colindices = el.index(b'red'), el.index(b'green'), el.index(b'blue'), el.index(b'alpha')
             if -1 in colindices:
                 colindices = None
             else:  # if not a float assume uchar
@@ -267,6 +267,7 @@ def load_ply_mesh(filepath, ply_name):
             mesh_colors.append([(vertices[index][colindices[0]] * colmultiply[0],
                                  vertices[index][colindices[1]] * colmultiply[1],
                                  vertices[index][colindices[2]] * colmultiply[2],
+                                 vertices[index][colindices[3]] * colmultiply[3],
                                  ) for index in indices])
 
     if uvindices or colindices:
@@ -340,7 +341,10 @@ def load_ply_mesh(filepath, ply_name):
                         f_col = f.color1, f.color2, f.color3
 
                     for j, col in enumerate(f_col):
-                        col.r, col.g, col.b = ply_col[j]
+                        col[0] = ply_col[j][0]
+                        col[1] = ply_col[j][1]
+                        col[2] = ply_col[j][2]
+                        col[3] = ply_col[j][3]
 
     mesh.validate()
     mesh.update()
diff --git a/io_scene_fbx/export_fbx.py b/io_scene_fbx/export_fbx.py
index dc647f71..e62d512d 100644
--- a/io_scene_fbx/export_fbx.py
+++ b/io_scene_fbx/export_fbx.py
@@ -1508,13 +1508,13 @@ def save_single(operator, scene, filepath="",
         collayers = []
         if len(me.vertex_colors):
             collayers = me.vertex_colors
-            t_lc = [None] * len(me.loops) * 3
+            t_lc = [None] * len(me.loops) * 4
             col2idx = None
             _nchunk = 4  # Number of colors per line
             _nchunk_idx = 64  # Number of color indices per line
             for colindex, collayer in enumerate(collayers):
                 collayer.data.foreach_get("color", t_lc)
-                lc = tuple(zip(*[iter(t_lc)] * 3))
+                lc = tuple(zip(*[iter(t_lc)] * 4))
                 fw('\n\t\tLayerElementColor: %i {'
                    '\n\t\t\tVersion: 101'
                    '\n\t\t\tName: "%s"'
@@ -1523,7 +1523,7 @@ def save_single(operator, scene, filepath="",
                    '\n\t\t\tColors: ' % (colindex, collayer.name))
 
                 col2idx = tuple(set(lc))
-                fw(',\n\t\t\t        '.join(','.join('%.6f,%.6f,%.6f,1' % c for c in chunk)
+                fw(',\n\t\t\t        '.join(','.join('%.6f,%.6f,%.6f,%.06f' % c for c in chunk)
                                             for chunk in grouper_exact(col2idx, _nchunk)))
 
                 fw('\n\t\t\tColorIndex: ')
diff --git a/io_scene_fbx/export_fbx_bin.py b/io_scene_fbx/export_fbx_bin.py
index e9e1248e..a630f86b 100644
--- a/io_scene_fbx/export_fbx_bin.py
+++ b/io_scene_fbx/export_fbx_bin.py
@@ -1061,9 +1061,9 @@ def fbx_data_mesh_elements(root, me_obj, scene_data, done_meshes):
     vcolnumber = len(me.vertex_colors)
     if vcolnumber:
         def _coltuples_gen(raw_cols):
-            return zip(*(iter(raw_cols),) * 3 + (_infinite_gen(1.0),))  # We need a fake alpha...
+            return zip(*(iter(raw_cols),) * 4)
 
-        t_lc = array.array(data_types.ARRAY_FLOAT64, (0.0,)) * len(me.loops) * 3
+        t_lc = array.array(data_types.ARRAY_FLOAT64, (0.0,)) * len(me.loops) * 4
         for colindex, collayer in enumerate(me.vertex_colors):
             collayer.data.foreach_get("color", t_lc)
             lay_vcol = elem_data_single_int32(geom, b"LayerElementColor", colindex)