PDA

View Full Version : March Entry:Grinding the river handle



Redrobes
03-06-2009, 01:01 PM
New challenge huh ? Well its a bit technical this one. Also the process to put rivers in is a methodical one hence my title. Its about climate and topology, a little geology and basically doing the water runs downhill thing.

Heres my previous tut on the subject. Which was based on a lot of others peoples comments as well.
http://www.cartographersguild.com/showthread.php?t=3822

Obviously ill be using my GTS to chug out the rivers so ill need the topology. Then since the challenge does not call for just rivers but a sh*t load of rivers, I had better turn on the taps and let the rain flood out. No need for me to fix up all those pesky little pools it tends to generate this time then.

So for my first WIP, I had better actually get that image knocked into shape. After a clean up job, and an edge detect then it comes out nice and large like this. I'll print this, get out my pen, draw some contours on it and scan it back in again. I find that quicker than any computer process including a tablet.

### Latest WIP ###

jfrazierjr
03-06-2009, 01:54 PM
New challenge huh ? Well its a bit technical this one. Also the process to put rivers in is a methodical one hence my title. Its about climate and topology, a little geology and basically doing the water runs downhill thing.

Heres my previous tut on the subject. Which was based on a lot of others peoples comments as well.
http://www.cartographersguild.com/showthread.php?t=3822

Obviously ill be using my GTS to chug out the rivers so ill need the topology. Then since the challenge does not call for just rivers but a sh*t load of rivers, I had better turn on the taps and let the rain flood out. No need for me to fix up all those pesky little pools it tends to generate this time then.

So for my first WIP, I had better actually get that image knocked into shape. After a clean up job, and an edge detect then it comes out nice and large like this. I'll print this, get out my pen, draw some contours on it and scan it back in again. I find that quicker than any computer process including a tablet.

### Latest WIP ###

Don't forget, the sample rivers provided can't be changed more then a tiny amount, so not sure how your application will handle existing river beds.

Redrobes
03-06-2009, 02:05 PM
It should be alright. I will tell it where they are and try to get the terrain around them right. If I get that wrong then it will move them.

Well, here is my effort with a pen and a scanner. This has been touched up from the original scan. Ill have to fill this in with height bands and get a 3D map.

### Latest WIP ###

Redrobes
03-06-2009, 02:43 PM
Just dropped graduating colors into the spaces between contours and then blurred it a bit to get height map.

### Latest WIP ###

Steel General
03-06-2009, 03:37 PM
Go RedRobes Go! :D

misteradam
03-07-2009, 04:36 PM
thats an interesting way to do it. so this program can take the line art and assign height to the terrain?

Redrobes
03-07-2009, 04:43 PM
No, there are programs that can do that job tho. I got the bitmap with the contours in it and flood fill gray colors into it. Then that makes a greyscale height map which the program takes in. If you need a better example then look at my Dec07 challenge entry about the Inn on a hill. Theres example pics for it there.

I have been running it through a processing run today and its generated some water flow as follows. I have taken this as a reference and drawn the rivers over the top on a transfer, fix up challenge rule bits about the number of courses per square and will then assign those to the map.

Anyway, for now, here is the processed image.

### Latest WIP ###

Redrobes
03-07-2009, 06:05 PM
Got a bit more done...

### Latest WIP ###

Redrobes
03-07-2009, 06:36 PM
Heres my count. I seem to have too many courses by quite a long margin. My rough tally is about 40x1, 30x2, 14x3 and a handful of more than 3.

So I need to knock down a few 2's into 1's and get rid of 12x3+ courses to be exact.

Redrobes
03-07-2009, 07:22 PM
Ok I think this fits the full criteria so here is my final unless there are some comments to make me change my mind.

The program has cut into the mountains pretty bad but the param I need to switch on in order to fix that would change the edge of the land and deform it quite badly and I think it would probably cut off some of the fixed rivers too.

Its not done so well at the top and bottom of the map because it really needs to know what is beyond those boundaries to do a proper job. If there were sea just at the bottom then its most likely that the bottom rivers would all head down into the sea from there instead of taking a circuitous route around the mountain to join back up with the fixed river. Still I think its done a decent job and I am happy with that result.

Its very difficult to make topo height maps to match the existing lakes and rivers. I would always recommend making the height map first and seeing where that leads you in terms of rivers and lakes by grinding the river handle and plotting the courses.

### Latest WIP ###

jfrazierjr
03-07-2009, 08:48 PM
Its very difficult to make topo height maps to match the existing lakes and rivers. I would always recommend making the height map first and seeing where that leads you in terms of rivers and lakes by grinding the river handle and plotting the courses.

Which is EXACTLY why this is such a great challenge. Sometimes you(people in general) have to be forced to do something the hard way to realize that the other way is just SOOOO much easier.


btw, it might be instructional to others to post your quote above (and perhaps a link to your river tutorial) in the main thread....:)

Redrobes
03-22-2009, 12:00 PM
I thought I had better fix up that lake on the left with an outflow otherwise ill have to take the rap by the river police. I added some of the light map back in for some shaded relief too. Seems to be in vogue at mo ;)

### Latest WIP ###

Ascension
03-23-2009, 10:29 PM
This looks great Red...with some black or brown line work you could really give it that hand-drawn old-world flair. Cool.