Telling a Story:
Introduction to Bézier Curves
Lines and Curves tell a story
 Photos can be converted to vector graphics or ‘line-art’, and each change can alter the story being told.
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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
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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
 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.
Copyright © Texas Education Agency, 2013. All rights reserved.
Images and other multimedia content used with permission.
French curves
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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.
Old drafting toolbox with 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
Vectors vs. Bitmaps
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Vector images can be …
 Easily edited
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 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?
 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 .
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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 .
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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.
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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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