ABrush

Post date: Nov 05, 2016 11:16:53 AM

A framework for 3D Voxel modelling using 'brush strokes'.

The basic idea is that each brush is a procedure for placing or modifying blocks along a path.

The framework includes support for creating paths of various smoothness, adjusting the brush effect along the length of the path, and for working with a block palette.

To use:

1. A path is an array of (x,y,z) points. You define your path either programmatically using Python code or by placing blocks of increasing ID in the selection area. 

Programmatically: use path = [] and then repeated calls to path.append((x,y,z)) to add a number of key inflection points to the path, the you can call the brush(level,box,options,RAND,path,theBrush) method. level, box, options are the same variables passed to MCEdit's perform() method. RAND is derived in perform() and path is your array of key points that will be used to find the shape of the brush stroke. theBrush is a string which is the method name of your brush procedure.

2. A brush is a procedure that implements the following method signature:

def yourBRUSH(level,box,options,materials,overwrite,RAND,radius,path,arclength):

The name 'yourBRUSH' can be anything, but it must be used as the parameter when brush() is called, with the correct upper and lowercase and spelling.

These are the fields you can work with in your brush implementation:

level - this is an MCSchematic working area.

box - this is a BoundingBox defining the region of the working area

options - these are all the filter options from the user interface

materials - this is an array of (blockID,blockData) tuples, one for each material on the user interface BLOCKS tab.

overwrite - this is a boolean True or False. If True then any blocks in the target should be overwritten, otherwise if False then this brush should not replace blocks already in the workspace MCSchematic.

RAND - this is an instance of Random created with the user-specified seed. Use Random.randint(1,100) to generate a random integer, for example.

radius - this is the widest radius that the brush stroke should use. In the example line brush you can see that at either end of the brush stroke the line is 1 block only, and in the middle it is the size of this radius. If set less than 1 the framework will choose a radius based on the selection box height.

path - this is an ordered array of points that define where the brush will execute.

arclength - this is the step-size of each block along the path and can be used to determine how many degrees along the path the brush is at each point in the path. It can be used with trigonometric functions to smoothly scale the brush stroke size along the length of the path.