sweeping node graph changes for new rendering pipeline

The new rendering pipeline strives to simplify the nodes themselves as much
as possible and move much of the logic to an external rendering engine. This
change removes all of the responsibilities that no longer belong to the
nodes themselves and will soon be folded into the renderer.

app/node/generator/solid/solid.cpp

@@ -56,24 +56,18 @@ NodeOutput *SolidGenerator::texture_output()
   return texture_output_;
 }
 
-QVariant SolidGenerator::Value(NodeOutput *output, const rational &in, const rational &out)
+QString SolidGenerator::Code(NodeOutput *output)
 {
-  Q_UNUSED(output)
-  Q_UNUSED(in)
-  Q_UNUSED(out)
-
-  /*
-  // FIXME: Test code
-  if (texture_ == nullptr) {
-    QImage img(1920, 1080, QImage::Format_RGBA8888_Premultiplied);
-    img.fill(Qt::red);
-
-    texture_ = new QOpenGLTexture(img);
+  if (output == texture_output()) {
+    // FIXME: Not color managed
+    return "#version 110\n"
+           "\n"
+           "uniform vec4 color_in;\n"
+           "\n"
+           "void main(void) {\n"
+           "  gl_FragColor = color_in;\n"
+           "}\n";
   }
 
-  texture_output_->set_value(texture_->textureId());
-  // End test code
-  */
-
-  return 0;
+  return Node::Code(output);
 }