Skip to main content

My First Component

In this tutorial, you will learn more in depth how to modify the geometry of a component so that it follows its configurable size. It also covers the basics of presets, refactoring & debugging. As a product example, we will use a configurable flat metal bracket with some holes.

For this we will follow 5 simple steps:

  1. Create app
  2. Modify model
  3. Presets
  4. Refactoring
  5. Debugging

Don't forget to check the common mistakes if you get stuck. Good luck!

1. Create App​

As done in My First App:

  • create a new app and name it for example Bracket App.
  • create a new component called e.g. Bracket.

Skip the connection between the app and the component, since this tutorial focuses on the component and its geometry.

Understanding how the component is structured is the key to create your app in the best way possible. When you go into a component (by clicking the thumbnail or its name Bracket), you can see the code (right) that generates the preview (left):

  • On the right side of the code (right), you find:

    • PRESETS COMP to generate different looks of your component with a specified set of properties.
    • PRESETS 2D to generate different looks of your functions that generate 2D geometry.
    • PRESETS 3D to generate different looks of your functions that generate 3D geometry.
    • TEST to create tests that can involve multiple behaviors of the component and its functions (we skip this for now).
    • API: intended for advanced features (we skip this as well for now).
    • PARAMETERS to generate configurators with parameters that can modify the model.
    • GEOM3D to define the 3D geometry of the component.
    • GEOM2D to define the 2D geometry of the component.
    • CONSTANTS to store all your constants.

  • On the top-left side of the preview (left), you find (starting from above):

    • the tabs Component, 3D and 2D to switch between which type of preset you want to visualize.
    • a dropdown with all the presets available of the type of preset selected above, that come from PRESETS COMP, PRESETS 2D and PRESETS 3D respectively (we will come to this part later).
    • a dropdown with all the configurators available, that come from PARAMETERS.

2. Modify Model​

We will modify the model in 5 different steps:

A. Flat sheet​

To change the height of the cube, we need to update its default property value.

  • In COMPONENT, notice that in the constructor we have the properties width, depth & height.
  • Change the default value of height from 100 to 2:
constructor() {
  super()

  this.properties = {
    width: 100,
    depth: 100,
    height: 2,
  }
}
  • Save & Update to apply changes.

Don't worry about the case height = 0, we will fix it later.

B. Holes​

Let's add some holes that dynamically dis/appear depending on the size of the sheet. For now, let's add one in the middle.

  • In COMPONENT, notice that generateGeometry() is creating an extrusion as model.addExtrude()

  • Use the existing model to add the extrude cut afterwards with the proper arguments:

    • holeSketch as the sketch to define the shape of the cut.
    • plane as the plane from where the cut is done (on the ground by default, same for extrusion).
    • height for the length of the cut.
    generateGeometry() {
      // properties

      const model = new SKYCAD.ParametricModel()
      const baseSketch = SKYCAD.generateRectangleSketch(0, 0, width, depth)
      const plane = new SKYCAD.Plane()
      model.addExtrude(baseSketch, plane, height)

      const holeSketch = SKYCAD.generateCircleSketch(width / 2, depth / 2, 7) // position = (width / 2, depth / 2); diameter = 7
      model.addExtrudeCut(holeSketch, plane, height)

      // color & material

      const geometryGroup = new SKYCAD.GeometryGroup()
      geometryGroup.addGeometry(model, { materials })

      // layout with dimension

      return geometryGroup
    }

  • Save & Update to save the changes and update the model with the hole.

Perfect! We will repeat this process for more holes in the rest of the corners, but we will add some rules so the holes don't collide with each other for example. As an example you can have the following:

generateGeometry() {
  // properties

  // Extrusion
  const model = new SKYCAD.ParametricModel()
  const baseSketch = SKYCAD.generateRectangleSketch(0, 0, width, depth)
  const plane = new SKYCAD.Plane()
  model.addExtrude(baseSketch, plane, height)

  // Holes
  const MARGIN = 15

  if (width <= 50 && depth <= 50) {
    const holeSketch1 = SKYCAD.generateCircleSketch(width / 2, depth / 2, 7)
    model.addExtrudeCut(holeSketch1, plane, height)
  } else if (width > 50 && depth <= 50) {
    const holeSketch1 = SKYCAD.generateCircleSketch(MARGIN, depth / 2, 7)
    const holeSketch2 = SKYCAD.generateCircleSketch(width - MARGIN, depth / 2, 7)
    model.addExtrudeCut(holeSketch1, plane, height)
    model.addExtrudeCut(holeSketch2, plane, height)
  } else if (width <= 50 && depth > 50) {
    const holeSketch1 = SKYCAD.generateCircleSketch(width / 2, MARGIN, 7)
    const holeSketch2 = SKYCAD.generateCircleSketch(width / 2, depth - MARGIN, 7)
    model.addExtrudeCut(holeSketch1, plane, height)
    model.addExtrudeCut(holeSketch2, plane, height)
  } else {
    const holeSketch1 = SKYCAD.generateCircleSketch(MARGIN, MARGIN, 7)
    const holeSketch2 = SKYCAD.generateCircleSketch(width - MARGIN, MARGIN, 7)
    const holeSketch3 = SKYCAD.generateCircleSketch(MARGIN, depth - MARGIN, 7)
    const holeSketch4 = SKYCAD.generateCircleSketch(width - MARGIN, depth - MARGIN, 7)
    model.addExtrudeCut(holeSketch1, plane, height)
    model.addExtrudeCut(holeSketch2, plane, height)
    model.addExtrudeCut(holeSketch3, plane, height)
    model.addExtrudeCut(holeSketch4, plane, height)
  }

  // color & materials

  const geometryGroup = new SKYCAD.GeometryGroup()
  geometryGroup.addGeometry(model, { materials })

  // layout with dimension

  return geometryGroup
}
  • Save & Update to see the dynamic holes in each corner.

Try different values for the parameters width and depth and see how the holes behave when having values lower and higher than 50 in this case.

C. Fillet​

As a third step, we can also round the corners. For that we can simply add fillets for each node of baseSketch.

generateGeometry() {
  // properties

  // Extrusion
    const CORNER_RADIUS = 10
    const baseSketch = SKYCAD.generateRectangleSketch(0, 0, width, depth)
    baseSketch.getNodes().forEach((node, nodeId) => {
      baseSketch.addFillet(CORNER_RADIUS, nodeId)
    })

    const model = new SKYCAD.ParametricModel()
    const plane = new SKYCAD.Plane()
    model.addExtrude(baseSketch, plane, height)

  // holes

  // color & materials

  const geometryGroup = new SKYCAD.GeometryGroup()
  geometryGroup.addGeometry(model, { materials })

  // layout with dimension

  return geometryGroup
}
  • Save & Update to see the rounded corners.

D. Color​

Changing the color of the component is very easy and has to be changed when adding the model to a geometry group, which contains information about the position, rotation and materials.

  • In COMPONENT, go to generateGeometry().
  • See that the model is added to the geometry group with materials, which contains the color.
  • Similarly as done in My First App, set it to gray as: 
    const color = new SKYCAD.RgbColor(200, 200, 200)
  • Save & Update to see the new color.

E. Update Configurator​

And last but not least, we will refine the parameters to adjust their values according to the product, i.e. bracket here.

  • Go to PARAMETERS and see that the function generateConfigurator() creates the configurator you see in the preview.

If you look closely, the default generateTestConfigurator() generates a configurator based on the properties of the component if all these are numeric. However all these default parameters have a predefined range of values. Therefore, we want to have a parameter for each property that it's easier to customize. For this:

  • replace the default generateConfigurator() with the following configurator, including:

    • 3 parameters, one for each property.
    • default values of parameters that come from the component properties.
    • configurator.addCompletionCallback() to update the properties from the parameter values.
    export function generateConfigurator(component: COMPONENT.Component): SKYPARAM.Configurator {
      const { width, depth, height } = component.getProperties()

      const widthParameter = SKYPARAM.generateSlider('width', 'Width (x)', {
        defaultValue: width,
        maxValue: 300,
        minValue: 20,
        stepSize: 0.1,
        unit: 'mm',
      })

      const depthParameter = SKYPARAM.generateInputParameter('depth', 'Depth (y)', {
        defaultValue: depth,
        maxValue: 300,
        minValue: 20,
        stepSize: 10,
        unit: 'mm',
      })

      const heightParameter = SKYPARAM.generateDropdown(
        'height',
        'Height (z)',
        [new SKYPARAM.DropdownItem('0.7', 0.7), new SKYPARAM.DropdownItem('2', 2), new SKYPARAM.DropdownItem('5', 5)],
        { unit: 'mm' },
      )
      heightParameter.setValue(height)

      const configurator = new SKYPARAM.Configurator([widthParameter, depthParameter, heightParameter])

      configurator.addCompletionCallback((valid, values) => {
        if (valid) {
          component.setProperties(values)
        }
      })

      return configurator
    }

Alternatively, you can use parameter keys if you don't want to mix properties with parameters:

Show configurator with different parameter keys:
const PARAMETER_KEY = {
  WIDTH: 'WIDTH',
  DEPTH: 'DEPTH',
  HEIGHT: 'HEIGHT',
}

export function generateConfigurator(component: COMPONENT.Component): SKYPARAM.Configurator {
  const { width, depth, height } = component.getProperties()

  const widthParameter = SKYPARAM.generateSlider(PARAMETER_KEY.WIDTH, 'Width (x)', {
    defaultValue: width,
    maxValue: 300,
    minValue: 10,
    stepSize: 0.1,
    unit: 'mm',
  })

  const depthParameter = SKYPARAM.generateInputParameter(PARAMETER_KEY.DEPTH, 'Depth (y)', {
    defaultValue: depth,
    maxValue: 300,
    minValue: 10,
    stepSize: 10,
    unit: 'mm',
  })

  const heightParameter = SKYPARAM.generateDropdown(
    PARAMETER_KEY.HEIGHT,
    'Height (z)',
    [new SKYPARAM.DropdownItem('0.7', 0.7), new SKYPARAM.DropdownItem('2', 2), new SKYPARAM.DropdownItem('5', 5)],
    { unit: 'mm' },
  )
  heightParameter.setValue(height)

  const configurator = new SKYPARAM.Configurator([widthParameter, depthParameter, heightParameter])

  configurator.addCompletionCallback((valid, values) => {
    if (valid) {
      component.setProperties({
        width: values[PARAMETER_KEY.WIDTH],
        depth: values[PARAMETER_KEY.DEPTH],
        height: values[PARAMETER_KEY.HEIGHT],
      })
    }
  })

  return configurator
}
  • Save & Update to apply changes to the configurator.

3. Presets​

Once you have the configurator set up, you might wonder: would I need to play with the parameters to see all the edge cases? In DynaMaker is possible to create pre-defined versions (i.e. with different property values) of your component as pure visualization tests, we call them Presets. These allow us to try different values of the parameters (Width (x), Depth (y) & Height (z)) within the component without going to the UI or any other component. The advantage of this is that you can immediately see how the parameters affect your new features, e.g. the distribution of holes in this case. And most importantly, these presets are saved! Let's put these words into action:

  • Still in the component Bracket, go to PRESETS COMP.
  • Under preset add the edge cases you want to see. For example, try these to see the distribution of holes at width = 50 with the code we wrote before in section B. Holes. See that the function preset.addCase() takes the set of properties you want to change as input. The second optional input would be the optional arguments related to the preset item itself, like the label.
export const preset = new PRESET.ComponentPreset(COMPONENT.Component, {
  setCameraOnUpdate: false,
})

preset.addCase({ width: 50, depth: 150, height: 0.7 }, { label: '50 x 150 x 0.7' })
preset.addCase({ width: 51, depth: 150, height: 0.7 }, { label: '51 x 150 x 0.7' })
  • Switch between components presets in the dropdown at the top-left corner of the _Preview_.
  • Keep adding more presets until you covered all the edge cases, e.g. in this case:

4. Refactoring​

Cleaning the code or refactoring is quite important to make clear what you do in your components. Remember that you might not be the only one working on the project, so whatever you write has to be clear for anyone jumping into your project at any stage.

Imagine that someone wrote a function that does a lot of complex calculations. It works perfectly until 1 month later when a new feature is requested. Then the calculations must be changed and some things are wrong or simply not useful anymore. And add the extra difficulty when the developer that has to fix it is you and not the person that wrote it initially.

So as a first recommendation, keep things where they should be. In this case, you have might have noticed that generateGeometry() starts to feel messy, and it's because it does too many things. As a general rule, if you break a function into subfunctions with a specific logic, then it might be easier to read.

In this case we create both the models and sketches in COMPONENT (within generateGeometry()), but we could move the models to GEOM3D and the sketches and layouts to GEOM2D, so like:

// GEOM2D
export function generateBaseSketch(width: number, depth: number) {
  const CORNER_RADIUS = 10
  const baseSketch = SKYCAD.generateRectangleSketch(0, 0, width, depth)
  baseSketch.getNodes().forEach((node, nodeId) => {
    baseSketch.addFillet(CORNER_RADIUS, nodeId)
  })
  return baseSketch
}

export function generateHoleSketch(posX: number, posY: number) {
  const HOLE_DIAMETER = 7
  const holeSketch = SKYCAD.generateCircleSketch(posX, posY, HOLE_DIAMETER)
  return holeSketch
}

export function generateDimensionLayout(width: number) {
  const layout = new SKYCAD.Layout()

  const start = new SKYMATH.Vector2D(width, 0)
  const end = new SKYMATH.Vector2D(0, 0)
  layout.addDimension(start, end, { offset: 20, decimals: 1 })

  return layout
}
// GEOM3D
export function generateModel(width: number, depth: number, height: number) {
  const model = new SKYCAD.ParametricModel()
  const plane = new SKYCAD.Plane()
  const baseSketch = GEOM2D.generateBaseSketch(width, depth)
  model.addExtrude(baseSketch, plane, height)

  const MARGIN = 15

  if (width <= 50 && depth <= 50) {
    const holeSketch1 = SKYCAD.generateCircleSketch(width / 2, depth / 2, 7)
    model.addExtrudeCut(holeSketch1, plane, height)
  } else if (width > 50 && depth <= 50) {
    // and so on with the rest of the holes
  }

  return model
}

Remember to export the function in GEOM2D (and GEOM3D) if you want to use it anywhere else, or you won't be able to use it in e.g. GEOM3D. Also, the code completion should help you notice that.

Then once cleaned up the geometry-generators functions, we can clean generateGeometry(), e.g. like:

// COMPONENT
generateGeometry() {
  const { width, depth, height } = this.getProperties()

  const geometryGroup = new SKYCAD.GeometryGroup()
  const model = GEOM3D.generateModel(width, depth, height)
  geometryGroup.addGeometry(model, {
    materials: [new SKYCAD.Material({ color: new SKYCAD.RgbColor(200, 200, 200) })]
  })

  const layout = GEOM2D.generateDimensionLayout(width)
  geometryGroup.addGeometry(layout)

  return geometryGroup
}

See that the functions are not only much easier to read, but also ready for future reusability!

And as a second recommendation, keep things with a proper name, so when you read it you know what it does. In this case in GEOM3D, having 50 everywhere is bad because you might wonder later what does this 50 mean? For that, you should keep these numbers in variables or const. And also, as soon as you use something twice, try to move it to a common place, like CONSTANTS. For example:

// CONSTANTS
export const HOLE_DIAMETER = 7
export const SIZE_LIMIT_FOR_HOLES = 50

Having these, we can update some values that we wrote in previous functions:

// GEOM2D
export function generateHoleSketch(posX: number, posY: number) {
  const holeSketch = SKYCAD.generateCircleSketch(posX, posY, CONSTANTS.HOLE_DIAMETER)
  return holeSketch
}
// GEOM3D
// [...]
if (width <= CONSTANTS.SIZE_LIMIT_FOR_HOLES && depth <= CONSTANTS.SIZE_LIMIT_FOR_HOLES) {
const holeSketch = GEOM2D.generateHoleSketch(width / 2, depth / 2)
model.addExtrudeCut(holeSketch, topPlane, -height)
} else if (width > CONSTANTS.SIZE_LIMIT_FOR_HOLES && depth <= CONSTANTS.SIZE_LIMIT_FOR_HOLES) {
// [...]

5. Debugging​

When something is wrong in your component and you don't know exactly where the problem comes from, it's time for stepping into the code and check what's happening at specific points, also known as debugging.

Let's show a typical problem that can be fixed in 1 line of code. Taking the component we have made as an example, we have recreated the app and introduced an intentioned bug. Knowing that the UI has been modified to make it easier, are you able to find the width and depth that causes a bug with one of the holes in this app?

Show solution:

Exactly, when width < 50 and depth < 50 the hole gets misplaced.

Since it's related to geometry, what you would do is:

  • Go to your component (i.e. Bracket).
  • Create a new preset with the values you found the bug with (e.g. width = 20 and depth = 30).
  • Save & Update and make sure to use that preset.

Now you would see the problem clearly with those values. Let's start debugging:

  • Still in your component, go to GEOM3D.
  • Open the browser console (F12)
  • Type debugger right before you want to start debugging.
  • Save & Update to apply the change, Notice that it stops exactly at the line you typed debugger.
  • By pressing F10 you can go on with the debugging line by line.

In this case, we find that we have swapped depth & width in line 16, so the correct code should have been:

const holeSketch = GEOM2D.generateHoleSketch(width / 2, depth / 2)

// instead of
// const holeSketch = GEOM2D.generateHoleSketch(depth / 2, width / 2)

If you are getting other sort of errors (e.g. component crashes), you can read more about debugging here.

Congratulations! You have finished the second tutorial. Having the component in an app would look like this:


Do you want to have a copy of this app in your team? Let us know at support@dynamaker.com! Remember that everyone has their own way of developing and there are multiple valid ways to do things as long as anyone can understand the code!

Now that you know how to create components, let's create an assembly with multiple components in the next tutorial My First Assembly.