As a newbie, can anyone please tell me how to erase/delete a painted surface without deleting the physical face below ? Also want to know how I can set the faces( front and back) to be the same white colour all the time without having to reverse faces when necessary? Many thanks Ant
Repaint the face with the default material. You can access it by clicking on the “dive flag” button in the upper right corner of the Materials window.
Get in the habit of correcting face orientation. Not doing so can cause you confusion and delay later. I have my back face color set to a color I wouldn’t normally use in my models so it’s easy to see. If you practice clean modeling techniques including keeping face orientation correct as you go, your models will be much easier to work with.
Hello. A painted face is the same as a textured face. To remove texture you can select all your geometry (triple click on it) and click the little ‘Set Material to Default’ button like in the GIF below:
About the second question, SketchUp faces MUST have 2 sides (a question to experts, by the way, why is this so necessary?). Hence it’s best to have 2 default colours for faces, one lighter than the other, to distinguish them. The lighter coloured face is the one that should always face out. You should apply materials/paint to the lighter (front) face only. If you have faces that show their back side (no pun intended, haha), right click and choose ‘Reverse Faces’
If you have many disoriented faces, one way to fix them all is to right click on a correct, front face and choose ‘Orient Faces’.
HINT: Try to avoid texturing groups. Rather put textures on the actual meshes to avoid future confusions.
A somewhat facetious answer: what would a face with only one side be like (sound of one hand clapping). I suppose you could draw it using edges with only one end?
Thank you Dave. That was very helpful. Those were my first questions and if this is how efficient and friendly the forum is that is wonderful! Ant
Think about it this way:
- A face exists in only 2 dimensions - i.e. on a plane
- But in SketchUp, we’re looking at it in 3 dimensions. We can position the camera so that it looks like a line (camera in same plane as the face), but most often, our camera isn’t in the plane of the face.
- When the camera isn’t in the same plane, we are either looking at one “side” of the face or the other “side” of the face.
- It’s nice to be able to tell the difference!
Also, some people start modeling real world spaces (like houses) using walls, floors, ceilings, etc as faces with no depth. Now put up your favorite paisley wallpaper in the bathroom. Do you really WANT it to also visible from the street?
While this doesn’t address the internals of why faces must have a front and back, it does show some ways that having a front and back are useful!
Thank you for your tip and reply. Very helpful indeed. Ant
Thank you @sjdorst and @slbaumgartner. I was going to ask wouldn’t it be alright if we had 2 front faces instead of 1 front and 1 back but I think I see your point now. If we regard a face as a sheet of paper, I wouldn’t want to see my drawing show up from behind.
My SketchUp model shows a wall
With a Face that isn’t there at all!
It’s there when viewed the other way
I wish it wouldn’t hide that way!
Have appreciated reading both the questions and answers. I frequently want a surface to have a different colour on each side so that bit is useful to me.
The idea that a surface is going to remember which is front and which is back also explains why I have had problems handling them so the demo on reversing/orient is worth learning.
I have also just noticed I created one surface which was transparent in one direction and opaque colour in the other … weird. Comments welcome with that one.
You can “paint” each side of a surface with different materials. You can paint one side with a transparent color or material and it will be transparent from that side only.
It is also because we are not always working with sketchup only, it belongs to a world of several tools available for CAD that follow some rules. In many renderers, it can have a huge impact if face orientation is wrong.
Think also of all those plugins if we want to focus on sketchup only. I’m no expert in programming, but I believe many of them use formulas that involve face normal. and not giving a front or back to them would really make things harder. (try to ‘joint push pull’ (fredo’s plugin) many faces with different orientations)
Even the native push/pull tool needs it ! ( the two verbs explain it alright, it is push or pull, 0 or 1, positive or negative just like in the box at the bottom right hand corner with numerical values)
Edit : Oh dear, I should check more carefuly when the first post was… but still, if it may be useful !