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Telling a Story:
Introduction to Bézier Curves
Lines and Curves tell a story
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Photos can be converted to
vector graphics or ‘line-art’,
and each change can alter
the story being told.
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
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Telling a Story:
Introduction to Bézier Curves
Lines and Curves tell a story

For example, what do the red colored curves in the three
images below represent? What story are they telling?
Image 1
Image 2
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
Image 3
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Telling a Story:
Introduction to Bézier Curves
The story of Pierre Bézier
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Pierre Bézier developed the concept
in the late 1960s for manufacturing
automobiles for Renault.
This concept of drawing curves is
similar to using a French curve. A
French curve can be positioned to
draw a portion of any curved line.
French curves
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
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Telling a Story:
Introduction to Bézier Curves
Today’s Drafting Toolbox is found in
vector illustration software
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Bézier curves are now drawn in most
vector illustration software using the
pen tool (based on mathematical formulas).
Vectors are used in line drawings,
logos, and even web motion graphics
because file size remains small for
quick download over the Internet.
Vectors are also used in 3D technology
and are called spline curves or Nurbs.
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
Old drafting toolbox
with French curves
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Telling a Story:
Introduction to Bézier Curves
Vectors vs. Bitmaps
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Vector images can be …
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Easily edited
Resized because they are scalable
Printed smoothly at any size
Bitmap images …
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Store information by pixel, so they are
dependent on the number of pixels (resolution)
Suffer in quality when enlarged
Are better for photos and life like images
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
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Telling a Story:
Introduction to Bézier Curves
So how do you create lines and curves
with the pen tool?
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To create straight lines with the pen tool,
click and release. Move to a different place
and repeat. The ends of the lines are called
points or nodes.
Straight lines points are called corner points.
To create a curved line, click and drag. You
will create tangent handles. Handles change
the slope of the line.
Curved lines points are called smooth points.
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
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Telling a Story:
Introduction to Bézier Curves
Corners with Curves
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Curved lines that connect
at a sharp angles are
known as cusps.
They are also called
corner points with
independent direction.
They are created by
moving the tangent handle
while holding down the alt
key or the option key.
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
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Telling a Story:
Introduction to Bézier Curves
Strokes and Fills
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Lines in vector drawing programs
are called strokes.
The inside area of a vector is known
as a fill.
Strokes and fills may be turned off
or individually recolored. Gradients
and other effects can also be used.
Now, it’s time to tell your story with
lines and Bézier curves!
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
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