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That window shows the Sunlight Direction vector,
which we will use in TurboCAD to model solar shading.
In TurboCAD, select View > Lights... to bring up the Light Properties window.
Click “New.” The Light Parameters window for a new light source appears.
Set the Light Type to DIRECTIONAL – ON, and change the color to White:
Remember to make sure that the ON button is pressed down. It can be easy to forget
to turn a light source On.
The direction numbers (0.648709, 0.731650 and -0.209438) are the Sunlight Direction numbers from
the Visual Sun Chart Angles for this Chart window (see above).
You can type those numbers into that TurboCAD window, or simply copy/paste each number.
Now let's set up a second light source to provide some light within the shadows,
so that the shadows do not totally black out parts of the drawing. In the Light Properties window,
click “New.” This time, instead of Directional, we will choose HEADLIGHT.
Remember to press the ON button, and change the color to White.
Now the Light Properties window should have two light sources listed.
Click OK to close this window and return to the main TurboCAD program window.
Next we will set the Camera Properties.
Select View > Camera > Properties...
In the Camera Properties window, select Quality in the left pane, then set Rendering Type to
LightWorks, and set Rendering Mode to Raytrace Full:
Make sure “Perspective View” is UNCHECKED.
Finally, let's tell TurboCAD to view the drawing from the Northwest, so that we can get a better view of
where shade from the tree will strike the building. Select:
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View > Camera > Isometric > NW
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Now we're ready to render. To render the scene, select:
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View > Camera > Quality Render
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The scene is rendered like this:
Next, let's put a ground level plane in the scene, to show shade
striking the ground near the building. We'll turn off rendering while
we work on the drawing, and render again later. To turn off rendering,
press the Escape key.
Now that we are in drawing mode instead of render mode, let's switch to Plan View.
Select:
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View > Camera > Plan > By World
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You should be looking straight down at the scene now.
Any drawing we do here will be done on the X,Y plane.
We'll draw a box as a rectangle in this view.
First we'll create a new layer for the new entity.
To create the new layer, select Options > Layers...
Then click “New.” Then scroll down to the
new layer, usually called “Layer 1,” click on its name,
and type the name GROUND for this layer. Then click on that new layer's color
and change it to White.
Now we're ready to draw the rectangle.
Select Insert > 3D Object > Box.
Then you are prompted to click on the first vertex. This will be the upper left corner.
Click to the left and above the scene objects. Then click the second vertex,
which will be the lower right corner, to the right and below the scene objects.
You should now have a rectangle surrounding the building and tree.
In one of the TurboCAD menus usually below the drawing, there should be
3 numbers specifying the the Length, Width and Height of this new box.
The Height is originally Zero. Set it to -1. It must be negative, for
the box to extend below ground level (instead of above ground). After setting the Height to -1,
press the Enter key.
Now we need to put the box in the GROUND layer. Click on the Arrow selection tool,
then click on one of the rectangle's borders to make the rectangle the current object,
then Right click on one of the rectangle's borders and select Properties. Under “General” change the
Layer from 0 to GROUND, under “Pen” set the color to White, and click OK.
Then click outside of the drawing area to unselect the rectangle. It will disappear because
it is set to the same color as the background, but it will reappear later.
The new ground plane is now defined. Let's change the view and render again.
Set the view to Isometric Northwest:
View > Camera > Isometric > NW
To render, select: View > Camera > Quality Render
The scene is rendered with the new ground plane:
Note:
In some programs you can use Ambient lighting instead of Headlight.
DXF Technical Notes
In the DXF files exported from Visual Sun Chart,
all building facets and tree facets are exported as 3DFACE entities.
Each Gable Wall consists of two 3DFACE entities, with the border between them
turned off. Likewise, the Gable Rake fascias each consist of two 3DFACE entities
with the borders between them turned off.
All 3DFACE entities except tree tops are 4-point facets. Tree tops are 3-point
facets, but we include a 4th point equal to the 3rd point for safety. The DXF standard
allows DXF files to not include the 4th point if it is equal to the 3rd point, but
we include it anyway (in tree tops), in case a CAD program requires 4-point 3DFACEs.
All outward faces of 3DFACEs, except Roof Bottoms, should have Counter-Clockwise (CCW) Vertex
Winding. If you find any other 3DFACE entities that do not have CCW winding, let us know.
To be safe, you can select to render both sides of 3DFACE entities, which is the
default in many CAD programs.
Programmers should be able to identify facets by the Layer Name
and Comments (DXF comments are included where a layer name is
not enough to identify the type of facet).
In documenting the type of facet (in Layer Names and Comments),
sometimes the words FRONT, BACK, LEFT and RIGHT are used.
This terminology represents the building before it is rotated.
Assume the building is not rotated when interpreting
these terms; the Front Wall faces South, the Back Wall faces North,
the Left Wall faces West, and the Right Wall faces East.
Each wall also has a Left and Right Side; the Left Side of the Front Wall faces West,
while the Left Side of the Back Wall faces East.
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