Have a list of materials in the project. The user can assign materials to individual segments as well as the entire shape. The segments will be shown with a different color to indicate the material slot used. Subtractive shapes can be represented using dotted lines where additive shapes will have filled lines as usual. The materials assigned to the segments are used for the extruded sides of the mesh and materials assigned to the shapes themselves are used for the front and back faces of the mesh.

This will make it more user-friendly to change and extrude the same brush later in RealtimeCSG, as this way at least the materials are kept between updates. It also makes the regular meshes more useful. Requires #5.

Knife tool where you can draw a line to cut a shape into two shapes. In Blender that's keyboard shortcut K.

How do we handle modifiers? Apply them? Warn the user first "One or more shapes will be applied"? Only apply the modifiers that get cut? The user can simply undo the damage with CTRL+Z so perhaps asking is unnecessary.

Dragging and dropping image files on the grid to use them as backgrounds is much quicker than manually selecting them in the background settings window. We just don't want code duplication, there should only be one function that loads image files.

Background

In RealtimeCSG, brushes (convex meshes) are represented using the half-edge data structure (see here).

At the moment we convert all of the polygons of a generated convex mesh into planes and then feed those into a RealtimeCSG function that converts a set of planes into a brush. But converting planes (finding the intersection point of 3 planes, where sometimes there are infinite intersections) into a convex mesh is a difficult problem. That's why it often fails and has stability problems.

Your task

Build a function that can take a PolygonMesh (see here) and build a brush in the scene, by calling
BrushFactory.CreateBrush (see here). This requires generating the half-edge connectivity data.

Files

The C# function has been prepared and only needs contents. Here is a special version of the 2D Shape Editor that you can add as a package:

com.aeternumgames.shapeeditor.zip

Here is the Bounty.cs file, place this file in your RealtimeCSG installation (in your Assets directory):

RealtimeCSGBounty.zip

Try extruding using "RealtimeCSG -> Create Bevel" and you will get a notification in the console window that leads you to the function that needs to be written.

public static CSGBrush CreateBrushFromPolygonMesh(Transform parent, string brushName, PolygonMesh mesh)
{
	var controlMesh = new ControlMesh();
	var shape = new Shape();

	Debug.Log("Bounty code goes here! Thank you! <3");
	return BrushFactory.CreateBrush(parent, brushName, controlMesh, shape);
}

Tips

• A PolygonMesh is just a List of Polygon. They are convex n-gons (no triangulation) without duplicate normals.
• The payment of 50$ (or 50€ if preferred) will be made via PayPal after verifying your work.

Build a scrollable GuiList control that can display a list of GuiListItem with the ability to drag and drop order them around. Every GuiListItem should be able to hold regular controls. This list can then be used for a visual list of all shapes in the project and a list of materials etc. If the scrolling logic is stand-alone, like GuiScrollableContainer, it could then be used to scroll the contents of any window or control. This would be the preferred approach to implementing this as that could for example turn multiple inspector windows into one scrollable context-sensitive window.

A measuring tape that lets you place two points on the grid and then shows the distance between them.

A focus hotkey like F that automatically centers and zooms the entire selection into view.

Calculate the bounding box of the active selection and then ensure that's the active view (with panning and zooming).

All text appears blurry when on HIDPI screens (4K) with editor UI scaling ( > 1.25x ) applied.

Have a single-use keyboard tool that can bevel vertices, just like Blender.

Tooltips should disappear when the shape editor loses focus. It's been hard to find a way to reproduce the issue where tooltips show up outside of the shape editor window. Can it happen while the shape editor still has window focus?

Inspector windows in the bottom right corner can easily be lost when the user resizes the main window.

Idea: we could automatically close them when they are completely off-screen.

This function is supposed to be creating CSG brushes that require all polygons.

Have to remove the if (poly[k].hidden) continue; statements and do some tests.

Just like Blender, allow the user to type numbers while scaling, rotating or translating as a multiplier.

I already wrote the code for a simple keyboard recorder. The problem has been finding an elegant way to add this to tools without having to copy and paste the logic everywhere. Something almost as simple as a C# property for the tools that support this feature (or an input focus related thing).

#if UNITY_EDITOR

using System;
using UnityEditor;
using UnityEngine;

namespace AeternumGames.ShapeEditor
{
    /// <summary>Processes keyboard numbers for typing multipliers during active tools and widgets.</summary>
    [Serializable]
    public class NumericKeyboardRecorder
    {
        /// <summary>The accumulated string of characters.</summary>
        private string accumulator = "";

        private float lastValidFloat = 0.0f;

        /// <summary>Gets or sets (clears) whether the user has typed a value using the keyboard.</summary>
        public bool hasValue
        {
            get
            {
                if (accumulator.Length == 0) return false;

                return true;
            }
            set
            {
                if (!value)
                    Reset();
            }
        }

        /// <summary>The last valid value typed assuming <see cref="hasValue"/> is true.</summary>
        public float value => lastValidFloat;

        /// <summary>The text typed assuming <see cref="hasValue"/> is true.</summary>
        public string text => accumulator;

        /// <summary>Must be called on key down events.</summary>
        public bool OnKeyDown(KeyCode keyCode)
        {
            var character = (char)keyCode;

            // add floating point related characters to the accumulator.
            if (ValidateCharacter(character))
            {
                accumulator += character;
                UpdateValue();
                return true;
            }

            if (hasValue)
            {
                // backspace can be used to remove the last character.
                if (keyCode == KeyCode.Backspace)
                {
                    OnBackspace();
                    UpdateValue();
                    return true;
                }

                // minus can be used to negate the number.
                if (keyCode == KeyCode.Minus)
                {
                    OnMinus();
                    UpdateValue();
                    return true;
                }
            }

            return false;
        }

        // whitelist the input characters related to floating point numbers.
        private bool ValidateCharacter(char character)
        {
            switch (character)
            {
                case '0':
                case '1':
                case '2':
                case '3':
                case '4':
                case '5':
                case '6':
                case '7':
                case '8':
                case '9':
                case '.':
                    return true;
            }
            return false;
        }

        private void OnBackspace()
        {
            if (accumulator.Length == 0) return;
            accumulator = accumulator.Remove(accumulator.Length - 1, 1);
        }

        private void OnMinus()
        {
            if (accumulator.ContainsInvarianCulture("-"))
                accumulator = accumulator.Replace("-", "");
            else
                accumulator = "-" + accumulator;
        }

        private void UpdateValue()
        {
            if (ExpressionEvaluator.Evaluate(accumulator, out float number))
                lastValidFloat = number;
        }

        /// <summary>Resets the current input.</summary>
        public void Reset()
        {
            accumulator = "";
            lastValidFloat = 0.0f;
        }
    }
}

#endif

Allow the user to select an edge on two shapes and bridge the gap with a new shape between them.

With an existing edge selected, a vertex will be inserted on that edge and it will follow the mouse cursor. Click to place it and you will be dragging around the next vertex. Press enter to confirm (and discard the last vertex) or confirm with a precise click at the last vertex. The user can cancel the operation with the escape key.

Without any selection, you will see a vertex that follows the mouse cursor. Click to place it and you will be dragging around the next vertex. Press enter to confirm (and discard the last vertex) or confirm with a precise click at the last vertex. Obviously there will have to be at least 3 placed vertices, until that is the case ignore the enter key and let the user exit with the escape key.

Using Revolve Extrude with a Radius of 0 generates a degenerative quad in the center. This then causes errors in RealtimeCSG.

Using the RealtimeCSGTarget script throws the following info and error messages. This occurs when pressing the extrude or rebuild button. Sometimes this locks the editor UI and throws the GUI capture control warning we all love so dearly.

Perhaps there should be a pivot to flip against or some other fancy tool that makes it clear what's going to happen. Right now you have little control and the shape will appear to move around almost arbitrarily during the flip. Scaling by negative one -1 just like Blender with #8 could also improve this issue.

Boolean operations mistakenly consider these two shapes as a single shape with an infinitely thin point connecting them, causing the convex decomposition to fail. This will then cause a stack overflow and editor crash in the BayazitDecomposer. The splitting of this type of polygon at the singularity has yet to be fixed.

It's likely that PolyBoolJS (and thus PolyBoolCS) has this as an oversight in their algorithm. They scan lines vertically and end up merging them together. Maybe this is correct in their eyes. But we need a way to detect and split these singularities into multiple shapes. Whether you fix it here as a post-process or there in the core algorithm, it would be an incredible achievement and I will be super thankful!

Example Projects: S2D Projects Bad.zip

The payment of 50$ (or 50€ if preferred) will be made via PayPal after verifying your work.

When using symmetry it would be nice to be able to apply the mirrored shapes (insert them as regular shapes). Perhaps through the shape inspector window.

Pressing X or Y during a translate or scale operation to activate the constraints, will not modify the selection until you move the mouse. It should happen immediately upon activation. Preferably with as little code changed as possible.

Have a limit to the amount the user can zoom in and out, preferably the maximum amounts we can get away with in both directions, before the program fails to pan vertically and horizontally (among other issues).

Adding an option to invert the direction of an arch line segment whenever you want, possibly through a bool in the arch inspector.

Also at the moment when flipping a shape, the arch directions aren't flipped along with the rest, leaving them pointing out in the opposite direction.

For the measuring tool, it would be good if text could be rendered on an angle to follow the measuring line.

Brushes are built in 3D at their destination position (local space of the extrude target). The further you move away from zero the worse the floating point accuracy gets. This will eventually cause small faces to appear between brushes:

Building brushes near zero and then moving them to their destination could improve the stability.