The DeclaraCAD viewer has different rendering modes. These can be toggled from the context menu by right clicking and choosing from the rendering menu.
The default mode is shaded which draws face colors.
When shaded mode is active the options for raytracing, shadows, and reflections can be enabled to render a more realistic view. This requires more cpu/gpu processing and is thus disabled by default.
Wireframe mode shows free boundary and U/V iso lines.
HLR mode shows only visible lines which is useful for creating drawings.
Optionally you can toggle whether hidden lines are drawn.