Add lat/long versus relative support about mapcompose HOT 7 CLOSED

For conversion between lat/lon and x/y(0,1) you could use something like this:

fun Double.latToY01(): Double {
    val sinus = sin(clipLat(this) * PI / MAX_LONGITUDE)
    return 0.5 - ln((1 + sinus) / (1 - sinus)) / (4 * PI)
}

fun Double.lonToX01(): Double {
    return (clipLon(this) - MIN_LONGITUDE) / (MAX_LONGITUDE - MIN_LONGITUDE)
}

fun Double.y01ToLat(): Double {
    return 90 - 360 * atan(exp((this - 0.5) * 2 * PI)) / PI
}

fun Double.x01ToLon(): Double {
    return MIN_LONGITUDE + (MAX_LONGITUDE - MIN_LONGITUDE) * this
}

Ref code. I do agree though it would be great to have this inside the library with the checks for exceeding the MIN/MAX values.

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This library isn't tied to any measurement system. A map could be taken from a scanned paper or may represent the whole world. In the latter case, lat/lon make sense. However lat/lon may be irrelevant in other use cases.
Also, the relative to lat/lon formulas depend on the projection used to make the map.

Please provide more details about your usage of the library.

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@Nohus I am guessing that you just figured out how to put your projection on the Number of Block - Width x Number of Blocks -Height and figured out how to stack your imagery there. I will investigate putting WGS-84 on the map. The renderer of this map does seem really good to try and figure that out.

When I do that I can try and figure out each boxes bound points of lat and long and determine image coverage. Sorry I am talking this out loud so that it might paint a better picture. Then I can associate zoom to the respective 1:Altitude ratio of the imagery.

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Typically you know the extent in latitude and longitude of what you're rendering. Let's say Ya and Yb are respectively the projected coordinate in Y dimension of the top and the bottom. When y is a relative coordinate, it's projected coordinate in Y dimension is is Ya + y*(Yb-Ya). Then, the corresponding latitude is obtained using the relevant formula (which depends on the projection).

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I am not sure I understand completely but I will try my best to see what I can do. I understand the relative calculation, but I am trying to think of how to get the "blue marble map" to project correctly

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I think I will have to split bitmaps over a projection.

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