There are plenty of online tutorials, that can teach one to use Photoshop or adobe Illustrator. I don't know how to draw, but want to develop that skill, threfore I am looking for a good video tutorial or a book that can teach me.
An important aspect is that it has to teach me how to know what to draw, from the physics point of view. I call it that way, but it may be the wrong name for the painting undertanding approach. Let me provide an example:
Consider two images: one without
and one with the gradient overlay
So the gradient overlay from white to black in this case adds an effect of light dropping down on an object.
The next time I will be drawing something, I will know, that if I need to express a light on the object, I use gradient overlay.
I am looking for a resource that teaches me how to draw in this reality-related way.
Hope my question is understandable. If not really - let me know please, so I can break it down into a more logical pieces. Thank you.