Creating poison water

This is a tutorial for creating the poison water seen in Portal.

Construction

To add a water volume to your level, follow these steps:

1. Create a brush the size of the water volume using the Block Tool.
2. Open the Texture Browser by clicking the Browse button on the Texture Bar.
3. Double-click the tools\toolsnodraw material in the Texture Browser.
4. With your water brush selected, click the Apply Current Texture button to assign the tool textures|tools\toolsnodraw material to the whole brush.
5. Select the Texture Application tool, which opens the Face Edit mode.
6. Left-Click the top face of the water brush in the 3D view to select it.
7. Click Browse to bring up the Texture Browser again.
8. Select nature/hazard_liquid.
9. Click the Apply button on the Face Edit panel.

Now you will need to add the gas particle effect that floats above the surface of the water.

1. Select the Entity Tool.
2. In the Entities selection box, make sure the category is set to Entities and choose the object info_particle_system.
3. In the 3D view, click on the center of the top of your water brush to place the info_particle_system entity there.
4. Go into the properties window for the particle system by selecting it and pressing alt-enter.
5. Set the Particle System Name perameter to "water_mist_256"

ToDo:Trigger hurt