Draw On effect...

I need some help please.

I know the basics of Blender so I’m looking for a basic workflow and I can take it from there.

I am working on a 4 second video shot. It resembles - or it’s supposed to resemble - a typical graph/chart displayed on the screen. What I want to do is draw a bell-curve onto the graph over the span of 4 seconds.

In addition to simply drawing a bell curve onto the graph - in this particular sequence I want to drop letters and numbers (which fall into the scene from top and out of view), the numbers fall onto the bell curve and tumble down the right side of the curve after the curve has been drawn.

Any tips or ideas how I would accomplished this?

I love my Blender :slight_smile:

For your curve:


As for the text, unless you know how to script, you’ll either need to ALT+C (in object mode) to convert the text to curves or meshes then, back in edit mode, select all verts of each particular mesh or curve and either “P” to separate them so that they are individual entities or, CTRL+H> to add hooks to them individually so theat they are individually animatable.

If you have the text follow a path object rather than a curve then you can add a path constraint which will allow you much more freedom and control, not to mention headaches until you figure out how the system works.

In the following .blend file there are object and constraint IPOs for the letter T and a Path Speed IPO for the path object (The default is 100 frames but you can change that). I used a rotation IPO to keep th T facing forward (but a consrtaint could have been used here also) and a Follow Path constraint to get it to fall in line with the path over time. Just hotkey ALY+A with your mouse over the 3D window to see it in action.


What if you use dynamics to tumble the letters? Create a mesh object (that doesn’t render) to follow the shape of your bell curve and drop your individual letter objects (with spherical bounds, perhaps) onto the mesh.

Thank you for the replies. I am just now starting on this project. In my head, I’m trying to think of the ways to accomplish this.

Here is what I have so far:

  1. Create a chart I want to use as a background (i.e. backbuf)
  2. Create my bell curve as it would be in total using a bezier curve and extrusion.
  3. Set up the lighting and the camera angle.
  4. Create the text I want to use in the “tumbling effect”. And as mentioned above, separate the letters into separate meshes.
  5. Using the Game Engine physics, bake the falling letters onto the bell curve simulation.
  6. All sounds good thus far. Except. How would I create the “draw on” effect for the curve?

I detailed the process for another user in the first link that I posted above. You’re basically scaling a highly subdivided mesh along it’s Z axis when parented as a curve deform object. The trick is in getting the mesh aligned with the curve which is not too easy unless you know what you’re doing. The link explains exactly how to do it.