How to generate grass in SketchUp: Basic tutorial for V-Ray proxy, Skatter, Kerkythea Instancing Brush, 3D Tree Maker, and Make Fur

Lawn is one of the basic elements in garden designs which compose of grass and ground cover plants. In landscape and architectural visualization that specialized computer generated graphics (CGI), the most common way of rendering a lawn or ground cover area is trough optimizing the grass texture by applying bump map and maximize the setting, so that the ground will not appear completely flat. On the other hand, some visualizer would prefer to render the lawn in more realistic and detailed manner by adding three-dimensional (3-D) grass and scattering it on the ground surface. However, rendering a full 3-D grass object may increase the render time as well as the file size of the project. Thus, introducing such proxy grass, instancing, and other rendering features from different plugins help reduce the render time. There are various ways to generate grass and render it inside SketchUp. In this article, we will explore the various methods on how to generate 3D grass in SketchUp using different plugins, showing the basic step-by-step tutorials. Also, for your reference, I will provide a comparative analysis regarding the different plugins for SketchUp that specialize in making 3D grass. Here, I will indicate the set-up time and render time for each plugins in order to evaluate which plugin(s) shows a better performance.

For this test render experiment, I will be using the following plugins for SketchUp, emphasizing the 3-D grass feature: (1) V-Ray 3.4- proxy grass, (2) Skatter plugin, (3) Kerkythea- Instacing, (4) 3D Tree Maker plugin, (5) Make Fur plugin.


 1. Vray 3.4 (Proxy Grass)

STEP 1: Open the SketchUp, Using the ‘Rectangle’ tool, draw a ground plane model with 1x1 meter size then apply a vegetation texture on the surface.

STEP 2: Open the SketchUp file with 3-D grass model> select the entire grass model> right click> select ‘Make Group’.

STEP 3: Select the grouped 3-D grass model> using V-Ray toolbar, click ‘Export Proxy’> type your preferred file name> click ‘Save’.

STEP 4: Going back to ground plane model, click ‘Import Proxy’ under V-Ray toolbar option> select the last saved vrmesh file> then click ‘Open’.

STEP 5: Place the proxy grass on the ground plane.

STEP 6: Run a test render, notice that when you import your model into V-Ray proxy, all the assigned materials from the original model was gone. Take note that V-Ray proxies do not store the materials from the model, only the geometry and the material ID or assigned materials are stored.

STEP 7: In order to load the grass materials from V-Ray proxy, go to ‘V-Ray Asset Editor’> under ‘Materials’, select the V-Ray grass materials.

STEP 8: Under ‘Diffuse’, load the material from ‘Bitmap’ option> then select your preferred grass material from your folder> then click ‘Open’.

STEP 9: Copy the proxy grass. Fill the ground with proxy grass. When done, hit the V-Ray render button.

2. Skatter

STEP 1: Open the SketchUp, Using the ‘Rectangle’ tool, draw a ground plane model with 1x1 meter size then apply a vegetation texture on the surface. Plane surface should be oriented in front face. Set the ground plane into ‘Group’ or ‘Component’. NOTE: Skatter plugin can only work with groups and components. Thus, make sure that the surfaces and areas have to be grouped.

STEP 2: Using the Skatter plugin, click ‘Launch Skatter’> go to ‘Main’> under ‘Hosts’, click ‘Pick a grouped surface’> then select the grouped ground plane model. When done, a red mark will appear on the surface of the plane model in order to indicate the area where the ‘Skattered objects’ will emerge during the rendering process.

STEP 3: Using the Skatter plugin, open the ‘Skatter Library’> then choose any available grass materials from the menu. Here, we choose ‘Cut grass 01 (large)’.

STEP 4: Choose your preferred settings for the ‘Skattered objects’: (1) Default: Proxies and Render only, (2) Proxies, (3) Full geometry and render only, (4) Full geometry

STEP 5: Click the ground plane surface> wait for the ‘Skattered objects’ to generate.

RESULT SO FAR: ‘Skattered objects’ in different settings.

STEP 6: In order to re-surface the ‘Skattered objects’ from the plane, just click ‘Regenerate’ from the Skatter ‘Main’ menu. NOTE: There is no need to click ‘Regenerate’ if the ‘Skattered objects’ is loaded in ‘Full geometry’.

STEP 7: Click the render button using any available render plugins inside SketchUp. NOTE: During the rendering process, the ‘Skatter for SketchUp’ Version 1.4 in proxy settings can only works in the following render plugins: Vray, Thea, Maxwell, and Enscape. However, if you load the ‘Skatter objects’ in ‘Full geometry’, the objects can be rendered in any available rendering plugins for SketchUp.

 RENDER RESULT

3. Kerkythea (Instancing Brush)

STEP 1: Open the SketchUp, Using the ‘Rectangle’ tool, draw a ground plane model with 1x1 meter size then apply a vegetation texture on the surface.

STEP 2: Open the SketchUp file with 3-D grass model > select the entire grass model> right click> select ‘Make Group’. Copy (ctrl+c) the selected grass model.

STEP 3: Going back to ground plane model, paste the grass model on the plane surface.

STEP 4: Using Kerkythea toolbar, click ‘Export model to Kerkythea’> under ‘Export options’, click ‘Ok’

STEP 5: Choose a file location where you want to save your kerkythea file, type your preferred file name> then click ‘Save’. NOTE: Your model will be saved as .xml file.

STEP 6: Open the Kerkythea program> under ‘File’, click ‘Open’. Under ‘Open Scene’, select your last saved .xml file then click ‘Ok’.

STEP 7: Under ‘Models’, select all the grass materials> right click> click ‘Group’> then enter your preferred name. Here, I will be naming it as “Grass”. NOTE: We need to organize all the materials present in a particular model in order to easily select and unselect the materials when needed, especially when performing such kerkythea ’instancing brush’.

STEP 8: Under ‘Tools’, click ‘Instancing brush’. Here, a dialogue box for ‘Instancing brush’ will appear.

STEP 9: Under ‘Models’, right click on the “Grass” labeled material, then click ‘Select’. NOTE: The selected materials will be labeled with ‘Star’. Next, under ‘Instancing brush’ dialogue box, click ‘Instance’.

STEP 10: Go to ‘Models’, right click on the “Grass” labeled material, then click ‘Unselect’. Notice the labeled star will disappear.

STEP 11: Under ‘Models’, right click on the “Groundcover” material from the model, then click ‘Select’. NOTE: The selected materials will be labeled with ‘Star’. Next, under ‘Instancing brush’ dialogue box, click ‘Canvas’.

STEP 12: Change some parameters inside ‘Instancing brush’ dialogue box. Here, change the distance from 1.0 (default) to .01 canvas. This will enable us to populate the grass evenly in a small ground plane model.

STEP 13: In order to generate the grass, you can choose any operation from the ‘Instancing brush’ dialogue box such as ‘Populate’ or ‘Brush’. When you choose the ‘Populate’ option, the object will automatically multiply in random fashion, populating the surface of the selected canvas with grass object. On the other hand, when you choose the ‘Brush’ tool, you will need to manually apply the tool in the surface in order to populate the area with the grass object. In order to delete the excess object from the plane, you can use the ‘Eraser’ tool. As for now, we will be using the ‘Populate’ operation.

STEP 14: Click the ‘Render Start’ button. When done, click the ‘Rendered image’ icon, then save the file as JPEG or PNG.

 RENDER RESULT

4. 3D Tree Maker

STEP 1: Open the SketchUp, Using the ‘Rectangle’ tool, draw a ground plane model with 1x1 meter size. Apply a vegetation texture on the surface then select the ground surface. This will serves as a base for our grass model from ‘3D Tree Maker’ plugin.

STEP 2: Using ‘3D Tree Maker’ toolbar, click ‘Make grass’. A dialogue box will pop-up on your screen.

STEP 3: Under ‘3D Tree Maker- Make Grass’ dialogue box, choose your preferred plants or tree type. Here, we will be using the ‘grass00: Default Generic Grass’. Then select the surface of the ground plane model. When done, click ‘Place Instances’. This however will generate proxy grass on the ground plane. In order to produce denser grass, just click ‘Place Instances’ more than twice. NOTE: If you want to instantly generate a 3D grass in high-poly without going through a proxy settings, just uncheck the box from ‘Make proxies’ then click ‘Place Instances’.

RESULT SO FAR

STEP 4: In order to generate the 3-D grass from a proxy model, go to ‘3D Tree Maker’ toolbar, then click the ‘Redraw’ option. When done, click the render button using any available render plugins inside your SketchUp. Here, we will be using V-Ray for SketchUp.

RENDER RESULT

5. Make Fur

STEP 1: Open the SketchUp, Using the ‘Rectangle’ tool, draw a ground plane model with 1x1 meter size. Apply appropriate texture from the ‘Material dialogue box’. NOTE: When using ‘Make Fur’ plugin, all the materials applied in the ground plane model will automatically assigned to the grass model generated by the plugin. In order to generate the grass using ‘Make fur’ in proper orientation, make sure that the ground plane is set into front face (white face). To do that, select the plane model> right click> click ‘Reverse Faces’.

STEP 2: Select the ground plane model> open ‘Make Fur’ (Dialogue box or input box).

STEP 3: Under ‘Fur Settings’, change the value of ‘Rootwidth’ to 0.010 meter (10mm).

STEP 4: In order to generate the grass, select the surface of the ground plane model, then click ‘Make Fur’ or ‘Ok’. NOTE: In order to produce such denser grass, just click ‘Make Fur’, more than twice.

RESULT SO FAR

STEP 5: Click the render button using any available render plugins inside your SketchUp. Here, we will be using V-Ray for SketchUp.STEP 5: Click the render button using any available render plugins inside your SketchUp. Here, we will be using V-Ray for SketchUp.

RENDER RESULT

SUMMARY OF DIFFERENT RENDERED GRASS, GENERATED USING DIFFERENT PLUGINS FOR SKETCHUP

SAMPLE RENDER

Workflow: SketchUp+Skatter+Vray+PS+Picasa

Workflow: SketchUp+Skatter+Vray

Thank you for reading.