fix vertexcolor mesh without shading

Author: SimonDanisch

assets/shader/standard.frag

@@ -56,7 +56,6 @@ void write2framebuffer(vec4 color, uvec2 id);
 void main(){
     vec4 color = get_color(color, o_uv);
     {{light_calc}}
-
     write2framebuffer(
         color,
         o_id

src/visualize/mesh.jl

@@ -15,7 +15,8 @@ function _default{M <: GLNormalMesh}(mesh::TOrSignal{M}, s::Style, data::Dict)
     @gen_defaults! data begin
         shading = true
     end
-    if !shading
+    view = if !shading
+        # we need to remove the normals, because they're unused
         mesh = const_lift(x-> convert(GLPlainMesh, x), mesh)
     end
     @gen_defaults! data begin
@@ -30,10 +31,20 @@ function _default{M <: GLNormalMesh}(mesh::TOrSignal{M}, s::Style, data::Dict)
     end
 end
 function _default{M <: GLNormalVertexcolorMesh}(mesh::TOrSignal{M}, s::Style, data::Dict)
+    @gen_defaults! data begin
+        shading = true
+    end
+    if !shading
+        # TODO remove this hack in a more graceful way!
+        mesh = const_lift(mesh) do x
+            dict = attributes(mesh)
+            delete!(dict, :normals)
+            GeometryTypes.homogenousmesh(dict)
+        end
+    end
     @gen_defaults! data begin
         main = mesh
         boundingbox = const_lift(GLBoundingBox, mesh)
-        shading = true
         color = nothing
         shader = GLVisualizeShader(
             "fragment_output.frag", "util.vert", "vertexcolor.vert", "standard.frag",