How to intersect a texture with another mesh?

Question

I am trying to animate a logo. The logo is given as a 2D image. Now, I want to create the effect as if the ink is flowing along with the lines of the letter(s). Think as if you pour water in an empty riverbed and it starts to flow along the boundaries. I do not want to have a 3D effect here like real water flow in a valley but just as if an invisible pen is just drawing on a flat surface. (Any additional effects I will have to work out separately.)

I found this question. This uses an intersect modifier to restrict one mesh to a certain subspace.

In my case, I have an image as a starting point. I will either have to model a mesh manually according to the image template or I have to use a texture. Is it possible to do a similar approach affecting only the texture of the "canvas"? I thought about two planes with a minimal distance where the upper one will be cut (by modifiers) such that it allows to blend over the lower plane. I fear problems here with unwanted shadows and similar artifacts.

Or is there an easier solution I am completely missing here?

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Edit 1 As I was asked for an example, I have the problem that I do not have a ready-to-be-shown example here ;-). Although I found something similar to the effect I am searching for in this youtube video. You see as lines "appear from the invisible pen" of the author.

This example is just to see the effect of the drawing. I need it on a plane in 3D to do other fancy things later with the camera and additional objects. Secondly, of course, I do not want to draw the logo by hand but use the pre-existing image file if possible.

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Edit 2 I tried to make a blender file to show the effect at a single letter. It is not done very well just clicked together to see this roughly. I used the approach from the other question I mentioned to do boolean intersection.

Here I used a mesh but this is not 100% necessary. I just want the letter to be drawn over time. The camera will be animated which I did not do in the minimal example.

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Edit 3

As I was asked fo examples what I am planning/willing, I was pretty sure, I've seen a similar effect in an opening credit of a smaller cinema studio. Lookinf through maybe a hundred such credit scenes on youtube, I found 3 similar ones (but not the one I had in my mind):

• Regency (The light seems to be shining through a black plane)
• Good Universe (Drawing in thin air with sparklers)
• Screen Australia (The broad pencil drawing, not the letter)

The effect is always the same: The letters are appearing over time. I think the Regency video is closest to what I want to do but in reversed colors: I wnat to have a white (paper) plane and draw with dark (blue) ink.

Answer 1

In order to replicate the effect , as shown by the question you have given above , in 2d with textures you will have to use a different approach, which is by using the blender's node editor, the texture (here, logo) you want to apply the effect on should be added as an image texture in the node editor and then you will have to add a mix node and mix it with a transparent shader. Now, you can create a gradient and use a color ramp to tighten it up, also connect a Voronoi texture in between the texture node and mapping node in order to create a river like effect and use the x or y co-ordinates of the mapping node to make it go all the way from black to white ( if you want to inverse it just make it go from white to black and add an invert node after the color ramp ) and use it as a factor for the mix node. Finnaly you are going to achieve the effect you are looking for.