** Google Translate **
Hello, I do not really know where to expose this but I’ve noticed in the time that I’ve used blender that does not make calculations in a logical way, I mean, I give an example:
My scene is simple, a sun a plane a texture and a material, from frame 1 to frame 20, absolutely nothing happens in my scene, however for each frame I have to wait for a long time (In the internal renderer, in cycles it would be infinite ), and I do not understand why the program does not read the previous frame and says, Has any change been made? - Do not then copy and paste the previous frame, and once a change is made in the scene, just fence rendering the area in the I’ve made changes, the other thing is copying and pasting, because I do not need to renderize again and again a “tree” -for example- that has already rendered before and which has no change throughout the entire scene, please spread, if this can reach some developer, who can execute this welcome be-
Workaround for scenarios where theres most of the frame static or not changing is to use prerendered frame. You can setup one scene to render one frame and export it to file and other scene to use that file in video sequencer. Not only that t gives you speed but also gives you control of what is optimized since in later scene you could have some stuff rendered if needed and on top of prerendered frame.
Checking if any changes have been made is rather complicated to implement. This is technically possible, but requires some fairly deep changes to Blender.
Only re-rendering part of the images based on the objects that changed on the other hand is impractical. An object changing in one part of the scene can affect the lighting or shadows in any other part, and reliably determining that can be almost as much work as doing the render itself.
avoiding rendering can be automated in Blender without any code. With render layers and the compositor , you can save also a ton of rendering time with baking your objects.
This is a standard solution for long render times used by many people. It has its pros and cons like anything else.