Pseudo 3d with bitmap as displacement for y-axis

[Jerryscript]

I'm sure someone has already done something similar to this:

Using the basic focal length formula for simple 3d positioning of objects, I wanted a simple way to create a terrain. Creating a huge array of all the terrain points and elevations is tedious and time consuming. So, I thought, why not use a displacement map of sorts.

1-create a bitmap with a black background

2-draw an arial view of the terrain on the map, using an increase in the color value for each increase in elevation, so a mountain would be a collection of concentric circles with the color value increasing towards the peak of the mountain (topographical?)

3-when passing coordinates to the focal length formula, grab the pixel value of the bitmap at those coordinates and adjust the y value based upon the color returned, ie _y+=myBitmap.getPixel(x,z);

It seems to work great. Just wondering if anyone knows of any projects using such an idea, and if so, how does it perform under actual gaming conditions?

[Jerryscript]

Turns out the concept is called a Voxel engine. I threw together a quick example, and it seems to work well. This is in AS1, and it looks like if the concept were done in AS 2 or 3, the speed might be fast enough to be usable in a game. Attached is an example SWF and a txt file containing the AS1 used.

[Jerryscript]

There have been some excellent examples of this technique posted if anyone is interested:
http://board.flashkit.com/board/showthread.php?p=3956815#post3956815

[ArmoredSandwich]

thats pretty awesome what you got there, and the stuff on the forum XD

[Sirisian]

http://www.sirisian.templarian.com/flash/flashIsoWave/flashIsoWave.html

you mean like real-time? It's possible to render 3D terrain in flash fairly easily if you know what you're doing.

What you want to do is just make a heightmap. From what you said you might already know what they are. Make a bitmap and perlin noise it (black and white). Use the values between 0 and 255 for your height. If you know how to render triangle strips you should be fine.

[Jerryscript]

Sirisian, you basically restated what I posted, in slightly different terms :)

I'm curious to see some actual examples of this in use, not just tests scripts, but games or other apps using a Voxel engine. Know of any?

[Sirisian]

http://en.wikipedia.org/wiki/Heightmap

Nah, I don't normally use flash much. I was just giving you the real name for the process you were using.
http://www.google.com/search?hl=en&q=Flash+heightmap&btnG=Google+Search

brings up this height-map terrain:
http://mx.coldstorageonline.com/temp/flash8/perlin-landscape.html

I will point out that voxel terrain is very CPU intensive. It's only real advantage is it's ability to be used for destructible terrain allowing burrowing and such. Something a height-map can't do.

Here's a voxel one:
http://lab.parkstudio.ru/terra/

You know what amazes me is that none of them added in cloud cover. It's a really easy thing to add in for real-time effects. But again those voxel ones are so CPU intensive that even in C++ and such they can barely run in real-time normally, however the ones that do run in real-time are very cool.

Do you want the code for rendering a heightmap via triangles? aka the real way to render terrain. The example at the bottom of the page you posted shows quads being rendered.

[Jerryscript]

Thanks again Sirisian. I will definitely look over the code, though it's a side project I'm working on for my godson, so I only work on it when I'm with him.

FYI- it's a slightly different kind of webcam based game. Most webcam games use motion detection based on a blend mode or something similar, and that returns data for all motion detected. This one uses a pen-light source in a dark room to move the cursor using thresholds, and we wanted a terrain for the enemies, which is what got me interested in the Voxel concept. Thanks again for the info!

[Jerryscript]

I finally got a chance to work on what I was originally thinking of:

1- I create two bitmaps with perlinNoise, one for height mapping, one for color mapping

2- I render a perspective view by using the focal length formula and offsetting the y coordinate by the value of the height map, and setting the color with the color map

Note- steps one and two take up to 3 minutes to render depending on the size of the rendered cubes, to long for loading so....

3- I pass the pixel color values one row at a time to PHP/GD to convert the rendering to a PNG

4- I load the PNG and use the same perlinNoise height map to position objects via the focal length formula

Here are the sample files (the output to PHP/GD is disabled for viewing purposes), the Render example will take a long time and consume alot of resources!
Render (http://www.geocities.com/webwizardsways/flash/render.html)
Pre-Rendered (http://www.geocities.com/webwizardsways/flash/prerender.html)

Now I have to figure out a method for culling the objects. I'm thinking I can use the same perlinNoise function to create a set of masks, and set their layer such that objects going behind a hill will be masked appropriately. Any ideas for a better method?