4D Paint | Painting | Paint Brush
There are a number of other things you need to be aware of to ensure a fast update speed for your painting brush while in OpenGL. We will outline these next…
The paint brushes only work on Polygon Objects. So any procedural objects that you have in your scene will need to be made editable before you can paint on them.
Also the brush will only work on one selected object at time.
To speed up painting it is advisable to set the Texture Preview Size for a material to No Scaling. Although painting will work if this is not set, it may result in a much slower painting experience.
If you ever find your paint brush going slowly this is the first thing you should check.
If it is not set then C4D will continuously sample the texture you are painting on. It samples it so that it can display a lower resolution version in OpenGL. This process slows down the painting system. Setting it to No Scaling will use the full resolution texture directly on the object in OpenGL and no sampling will occur.
We also want the full resolution texture being displayed on the model so that we can see the details of the texture. So have a sampled down version is not actually useful for painting workflows.
Double click on your material and switch to the Editor Tab. Then make sure the "Texture Preview Size" is set to "No Scaling".
OpenGL likes images that are powers of 2. In some cases if they are not then it will upsize the image to ensure that it is. This causes additional computations that will just slow the brush down.
By making sure your textures are 256x256, 512x512, 1024x1024, 2048x2048 etc… will help ensure that the brush will get all the speed it can.
If you find the brush is going slowing try increasing the stamp spacing. Sometimes you don’t need to draw so many dabs onto the object to get the result you need. By increasing the stamp spacing it means it will do less drawing per stroke, which results in a faster brush performance.
Having a smaller brush size will help as well.
Together you can adjust your brush so that it will perform at its optimum speed while not causing any reduction in quality of the final textures.
If you are going to paint on multiple channels at the same time then you need to ensure that the textures are all the same size on every channel you are painting.