What is this?
MiBPov is the Minetest Biome Point Visualizer, a tool for people who develop games and mods for Minetest. It allows them to visualize the heat and humidity points of biomes. It works in your web browser using JavaScript.
Features
- Add the heat and humidity points of biomes
- Visualize the biomes on a Voronoi diagram
- Show biomes for a given Y altitude only
- Modify the noise parameters of the heat and humidity Perlin noises used by the mapgen
Quick reminder how biomes work
When Minetest generates the world, each (X, Z) coordinate is assigned a heat and humidity value (“heat” is also sometimes called “temperature”). Also, Minetest calculates the Voronoi cell for each biome. If a world position’s heat and humidity fall into a given biome’s Voronoi cell, that biome will be put at that position. And this happens for every position. The problem is that as you, as the developer, don’t see these Voronoi cells, you only see the heat and humidity points. This is where this program will help you.
Please refer to the official Minetest Lua API documentation for a more in-depth explanation.
Interpreting the diagram
On top of the page, you see the Voronoi diagram. The horizontal axis represents heat and the vertical axis represents humidity. The visible diagram area represents all mathematically possible values. Note that the further you go from the center, the less likely they will become, with the area close to the border being extremely unlikely (<0.1%). By default, the value range of heat and humidity is from −37.5 to 137.5, with 50 as the midpoint. But most values will be somewhere between 0 and 100 by default.
Red dots represent the biome points, and they are labelled by default by their (heat, humidity) coordinates. Dark green border lines represent the boundaries of Voronoi cells and the large colored areas represent the biomes themselves.
By default, a grid is displayed. A grid line is shown for every 10 units (unless the value range of heat or humidity is very large).
Below the diagram, a couple of status information is shown: The current altitude (Y coordinate), the heat and humidity range of the current diagram and your cursor position (if it is on the diagram).
An example
Let’s say there are 2 biomes at the (heat, humidity) coordinates (10, 10) and (90, 90). This will divide the diagram in 2 sections. Each of these sections is a Voronoi cell, or the set of all (heat, humidity) value pairs of that biome. Let’s look what happens at position heat=0, humidity=0. If you read the diagram, you will see it belongs to the first biome. This means that whenever a world position has a heat of 0 and humidity of 0, that biome will be used. Now at heat=70, humidity=50, we can read it belongs to the second biome. And this is how you can understand this diagram.
Usage
This section explains how you can interact with the various parts of the program.
The interactive sections have a header with an arrow symbol at the beginning. Click on this arrow to collapse or extend a section.
Diagram
Hover with the mouse cursor over the diagram to see the heat and humidity coordinates at this position.
You can click on a dot to select it, click on it again and hold down the mouse button to drag it. You can add a new point by double-clicking on the diagram, provided a click wouldn’t select an already selected point.
When you hover the diagram, a small grabbing widget will apper in the bottom left corner. You can use this to resize the whole diagram. Hold down Shift while resizing to preserve the aspect ratio.
Biome configuration
Here you can see a list of all currently active biomes. Each biome has a name of your choice. The program always starts with a default biome at (50, 50). Select a biome in the list so you can edit it.
The “Add” button adds a new biome with a random heat and humidity. “Remove” removes the currently selected biome.
Once you selected a biome in the list, the fields in “Selected biome” will activate. Here, you can edit the selected biome’s heat and humidity point (corresponds to heat_point and humidity_point in the Lua API). You can also edit the minimum and maximum Y level this biome will be generated in (corresponds to y_min and y_max).
Each biome has a name and a color which can be changed, too. These are only used for display purposes and don’t affect the calculations.
Changing a value in any of these fields will immediately take effect.
Diagram view settings
These settings only affect the visual representation and not the data. The checkboxes can be used to hide several things in the diagram, like the grid. The altitude setting changes at which altitude (Y coordinate) the diagram “looks” at. The diagram will only show biomes that would generate in this altitude, applying the biome’s Min. Y and Max. Y settings.
Note: If you hide the points, you can no longer select them in the diagram. You can still select them in the biome list, however.
Noise parameters
This is fairly advanced and most games don’t use this. You can use this if you want to see what happens if you use non-default heat and/or humidity Perlin noise parameters. This corresponds to the Minetest settings mg_biome_np_heat and mg_biome_np_humidity. The explanation of Perlin noises is out of scope for this document. See the Minetest Lua API documentation.
Changing the noise parameters has an effect on the possible value range for heat and humidity which is why this has been included. This also means the recommendation that you try to keep biomes between a heat/humidity roughly between 0 and 100 goes out of the window; you have to figure out a good range yourselves.
If your game or mod does not modify these noise parameters, you can ignore this section and leave it at default. Click on “Reset noise parameters” to reset them to the default if you accidentally changed them.
Import
This allows you to import biomes from JSON text that has been exported before (see below). If you have a JSON text, just paste it in the text box and press “Import”. This will replace all biomes. A message below the text box will tell you if the import has succeeded or failed. If the import has failed, nothing will happen.
Export
This allows you to export the current biomes into a text. You can choose to export them either to Lua code or JSON. The export only includes the basic biome info but not stuff like biome color (which is only relevant for MiBPoV) or noise parameters.
The Lua export gives you a very basic Lua code that can be pasted into an actual Lua mod. The code is very basic and does not include the “landscape materials”, like what the surface is made of (dirt, stone, sand, etc.).
The JSON export is a text you can use to import later. You could save this in a text file so you can import it later.
The Amidst for Minetest export gives you a biome profile you can use for Amidst for Minetest.
The “Clear” button clears the previous export. This is just there to reduce clutter on the webpage.
Caveats / Limitations
It is perfectly legal to have the biome points to be out of the bounds of the diagram. These out-of-bounds points are represented as arrows in the diagram. However, you can’t select them with your mouse on the diagram unless it’s close to the edge. Use the biome list to edit points that are out of bounds.
Heat/humidity values above 1,000,000 or below −1,000,000 are not supported and will trigger an error message. This is a much smaller range than what Minetest supports. Also, no diagram can be drawn if the heat or humidity noise scale equals 0 or is very small, although this is legal in Minetest. This does not mean that your chosen settings won’t work in Minetest, just that MiBPoV can’t visualize them.
MiBPoV does not visualizes the biomes of the v6 mapgen. This mapgen is special because it uses a completely different biome system.
MiBPoV assumes that the absvalue flag of the heat/humidity noises is always false. So if your game/mod has sets it to true, the diagram may still show a value range that is actually impossible.
Credits / License
This tool is free software. See the License page for details.