ADVERTISEMENT
LASN Technology Oct, 200410-01-04 | News



Quick Keys: Rendering an AutoCAD drawing in Photoshop

By Ashley Calabria, University of Georgia, Athens
Graphic Arts instructor

img
 




AutoCAD allows you to customize your layer palette. This sample will have the following list of layers: trees with shadows, blue trees, under story trees with shadows, under story trees, shrubs with shadows, shrubs, paving, water, turf, ground cover, house, patio and gazebo.


Part 2 – Rendering in Photoshop

Quick key articles are here to serve professionals in the field of landscape architecture, explaining in simple terms, basic computer skills. This is part 2 of a three-part article which takes the reader through the steps of: Part 1?EUR??,,????'??+ How to bring an AutoCAD drawing into Photoshop, Part 2 – Rendering the drawing and Part 3 – bringing the drawing back into AutoCAD layout for plotting.

There are some new things to keep in mind for this section of the article. Rendered objects on layers in Photoshop appear in the same hierarchy as they appear in the layers palette. For instance, a tree rendered on a layer but appearing beneath a shrub layer in the palette will look like the shrub is floating above tree. All you have to do is click and drag the tree layer in the palette to be above the shrub layer for it to be seen over it.

Another important step to remember is to NOT render on the base layer. It makes alterations more difficult. Layer management is very important. It would be wise to think of the items you plan on rendering and creating layers for them prior to starting.Layers named with shadows will have a drop shadow applied to those layers. The automatic effect of drop shadow is applied to everything in that layer.






After being selected from the plant palette, this large tree (green circle) is about to be placed on this layer or any other layer from the layer palette on the right.


One final thing to remember is that Photoshop will read the black lines of the drawing as a selectable area. If you want a line to show through a rendered object, the line needs to be unselected, so it won?EUR??,,????'???t be rendered over. The layer?EUR??,,????'???s opacity can also be lowered to see through the rendering to show lines or objects underneath it.

Let?EUR??,,????'???s get started!

Setting up the Layers

Go to the arrow (palette menu) in the layers palette and select ?EUR??,,????'??New Layer.?EUR??,,????'?? Rename it according to the layers needed for the project, then select OK. The layer will be added to the list in the layer palette. Do this process until all the layers have been made. Don?EUR??,,????'???t worry about their order for now, they can always be rearranged later. Other layers may also be added later if you aren?EUR??,,????'???t sure what layers to create.

Selection Options and Rendering

There are several ways to select areas that will be rendered. This article will review the most widely used methods for selection; elliptical marquee, magnetic lasso and the magic wand.

Elliptical Marquee

The elliptical marquee is excellent for selecting circular objects like simple tree shapes. It will be used to select the large tree in the bottom left corner of the drawing. First, zoom into the area of the object using the zoom tool and click on the area to work on. The magnifying glass will have a plus sign in it. If you zoom too close hold down the ?EUR??,,????'??Alt?EUR??,,????'?? key to zoom back out. The magnifying glass will have a minus sign in it.

Make sure you are on the base layer. Select the elliptical marquee by selecting on the upper left icon of the tool bar and selecting elliptical marquee tool.

Click starting from one side of a circle and drag an ellipse across a tree symbol. Holding down the shift key while dragging will turn the ellipse into a circle. Holding down the space bar at the same time allows the circle to move so it is more aligned with the shape of the object. Stay inside the black line of the circle. If the selection isn?EUR??,,????'???t what you want, go to Select and then Deselect and try again. You can also click back in the history palette.

Change to the layer that the selected object will be rendered on by selecting that layer in the layer palette. In this sample, the large tree rendering will go in the layer named ?EUR??,,????'??Trees with Shadows.?EUR??,,????'??

Using the Paint Bucket and brush to render

Select the paint bucket tool. This will fill the entire selection area with a solid color.

To select a color, click on the foreground color tool.

Scroll up the color bar and then select in the color box a light green. It is a good idea to start light and then go darker with the brush.

Once the color is selected, choose ?EUR??,,????'??OK.?EUR??,,????'?? Select inside the elliptical marquee. The color fills in the space.

Now use the air brush to highlight the sunny side and darken the shadow side of the tree.

Select the airbrush tool.

Up by the paint brush options, select a large textured brush like the ?EUR??,,????'??Spatter 58?EUR??,,????'?? pixels brush which is labeled 59.

Change the foreground color to a lighter color. This sample will use a light yellow to highlight the sunny side of the tree.

Now go back and select a darker foreground color to shade the shadow side of the tree. Select as many colors as you want to blend the two sides together.

Change the opacity of this layer so that items below it can be seen as well.

Once the rendering is finished, add a shadow to the layer by going to ?EUR??,,????'??Window?EUR??,,????'?? and ?EUR??,,????'??Show Layer Styles,?EUR??,,????'?? then select drop shadow from the selection menu.

Select different shadows to see their effects and find one that works for the drawing.

Once the tree and shadow are done, go to ?EUR??,,????'??Select?EUR??,,????'?? then ?EUR??,,????'??Deselect.?EUR??,,????'??



–––––––––

A Listing of different AutoCAD tutorials
on the internet ???????(C) 2000-2004, AlphaJade Pty Ltd.

Basic AutoCAD – Ploylines: A complete tutorial on the most common drawing tool in AutoCAD – the mighty polyline!
www.autocadcentral.com/Tutorials/Lesson 5/lesson5.htm

Autocad Central – Autocad Tutorials: Autocad Tutorials from Beginner to expert – Lines & Layers to 3D CAD Drawing
www.autocadcentral.com

Basic AutoCAD – Blocks: How to create, edit and redefine blocks in AutoCAD to make your drawings load quicker, and a lot easier to amend and edit.
www.autocadcentral.com/Tutorials/Lesson 12/lesson12.htm

Basic AutoCAD – Object Snap: A tutorial on the object snap settings in AutoCAD which help accurately draw from specific points.
www.autocadcentral.com/Tutorials/Lesson 11/lesson11.htm

Basic AutoCAD – Paperspace & Layout View: An in-depth tutorial explaining how to work with paperspace and layout views in AutoCAD, as well as print from these views to scale.
www.autocadcentral.com/Tutorials/Lesson 10/lesson10.htm

Basic AutoCAD – Hatching: Learn how to create and define hatch patterns to areas of your drawing. Includes downloadable AutoCAD files and interactive examples.
www.autocadcentral.com/Tutorials/Lesson 9/lesson9.htm

Basic AutoCAD – Using Text: How to create and edit notes and labels in your AutoCAD drawings.
www.autocadcentral.com/Tutorials/Lesson 8/lesson8.htm

Basic AutoCAD – An Introduction to Layers: Learn how to tidy up your drawings and arrange complex viewports using layers within AutoCAD.
www.autocadcentral.com/Tutorials/Lesson 7/lesson7.htm

Basic Autocad – Modify Commands: An in-depth tutorial on all of the powerful modify commands available in AutoCAD with interactive tutorials and example download files.
www.autocadcentral.com/Tutorials/Lesson 6/lesson6.htm

Basic AutoCAD – Drawing Limits: Uncover the usefulness of utilising drawing limits in AutoCAD.
www.autocadcentral.com/Tutorials/Lesson 4/lesson4.htm

Basic AutoCAD – Zoom and Pan: An introduction into finding your way around the AutoCAD drafting area using the zoom and pan tools.
www.autocadcentral.com/Tutorials/Lesson 3/lesson3.htm

Basic AutoCAD – Basic Commands: A refreshingly simple comprehensive tutorial on the basic drawing commands available in AutoCAD.
www.autocadcentral.com/Tutorials/Lesson 2/lesson2.htm

Creating Custom Bitmap Materials: This tutorial describes how to create custom bitmap based materials in AutoCAD and how to create the bitmap tile from scratch in Photoshop. www.cadtutor.netacadacad2kibitmatbitmat.html

AutoCAD to Photoshop: This tutorial explains in detail how to move your AutoCAD drawings into Adobe Photoshop.
www.cadtutor.net/acad/acad2ki/atop/atop.html

Drawing Aids: Drawing with AutoCAD is really just like drawing on a drawing board. Most newcommers to Computer Aided Design assume that they will need to learn how to draw all over again. This tutorial covers Ortho, Grid, Snap and Polar Tracking.
www.cadtutor.net/acad/acad2ki/aids/aids.html

Object Snap: The Object Snaps (Osnaps for short) are drawing aids which are used in conjunction with other commands to help you draw accurately.
www.cadtutor.net/acad/acad2ki/osnap/osnap.html


img