Recent Posts

1

Bridge Command General Support / Re: TerrainHeightMapSize

« Last post by forum_admin on Today at 08:57:58 AM »

Hi, with a normal greyscale image, 0 represents -1*SeaMaxDepth, and 255 represents TerrainMaxHeight, with linear interpolation in between. This actually means that the 'half way' between max height and max depth is between 127 and 128 greyscale values.

I made a simple calculator at https://www.bridgecommand.co.uk/data/_uploaded/file/Height%20conversions_255.xlsx which might be useful.

The relatively small number of steps available in a greyscale image is why there is also the 'RGB' encoding (height in metres is set by (red * 256 + green + blue / 256) - 32768), or raw 32 bit floating point format available, which both allow a much finer elevation step.

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Bridge Command General Support / Re: TerrainHeightMapSize

« Last post by rellufdarb on Today at 12:18:16 AM »

Hello Admin,

OK, makes sense.

I am just starting with Bridge Command. So far I have been trying to use (simple) greyscale .png files for height. I am having difficulty getting realistic shorelines--getting the slope right is hard and I usually end up with cliffs because I have the greyscale gradient too steep. To manually edit a large map has consumed many hours late at night already.

One question, for an 8 bit 256 level greyscale, is zero (water level) represented by 127 or half way between Max Height and deepest depth in the terrain.ini file?

3

Models / Re: Outboard Motors

« Last post by rellufdarb on Today at 12:13:26 AM »

There is obviously a lot of clever programming behind Bridge Command and I do have an electronics and programming background so I understand, but yes, I would think a "tweek" of azimuth drives would be one way to go. Just allow reverse thrust same as shaft drives but limit the rotation angles like rudders. The drives would have to be placed at the stern, but I see you already have parameters for the drive location.
In our case we have two outboard (on a rescue vessel) cross connected and steered from the one helm. I imagine both azimuth drives could be connected to the same joystick input so they turn together, just with separate throttle input for each.

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Models / Re: Outboard Motors

« Last post by forum_admin on April 22, 2024, 10:25:17 PM »

Thanks for asking. I'll have a look into this, I think it would be relatively simple to change the way the azimuth drive is modelled to allow reverse propulsion direction as an option.

I think you could get the right turning effect from tuning the rudder parameters, but I'm not sure the lateral motion would be realistic.

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Bridge Command General Support / Re: TerrainHeightMapSize

« Last post by forum_admin on April 22, 2024, 10:22:28 PM »

Hi, TerrainHeightMapSize is no longer required, so will now be ignored.

In earlier versions, it was previously required to specify the size of a square image defining the heightmap, but because this can be found directly from the image dimensions, it is not required any more.

If you are using a binary heightmap (a list of 32 bit floating point values), TerrainHeightMapRows and TerrainHeightMapColumns are now used instead, as non-square heightmaps are allowed.

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Bridge Command General Support / TerrainHeightMapSize

« Last post by rellufdarb on April 22, 2024, 01:59:18 PM »

In the Terrain.ini files I see this-----TerrainHeightMapSize----but it is not listed in the relevant documentation. At least I cant find it.
Where is this defined please?

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Models / Re: Outboard Motors

« Last post by rellufdarb on April 22, 2024, 03:29:50 AM »

Hmmm, just thinking and working my way through the file specs. I suppose if I use normal twin shaft propulsion and  if I deliberately increase the rudder effectiveness in Astern, that would have a similar effect as an outboard-IE it would "pull" the stern sideways? The big difference is that in real life, a rudder usually only has much effect if the vessel is making way whereas an outboard will turn the vessel "on the spot" as soon as revs increase and well before the vessel starts to move sternways through the water. Similar with ahead engaged too I suppose!

Thoughts anyone?

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Models / Outboard Motors

« Last post by rellufdarb on April 21, 2024, 01:44:32 PM »

How would I model twin outboards? I thought perhaps I could use Azimuth drives but they do not go astern and have to be rotated 180--not realistic for normal outboard operation.

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Bridge Command General Support / Re: Charts

« Last post by Guido on January 18, 2024, 12:06:54 PM »

I think you have to check if you get the GPS information. Otherwise it is going to 0,0 that is not the location of your map.

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Bug reports / Re: Various missing files

« Last post by reetp on January 07, 2024, 01:31:33 PM »

OK I'll give it a go!!