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pycairo.tar.gz

Pycairo

In this course, you will use Python’s Pycairo library to draw complex shapes. So if you have an appetite for virtual reality, or game development, then this course will serve you well.

You will start with basic concepts like: What is the difference between pixel and vector graphics? After that, you will learn to make basic drawings and then you will move on to complex shapes. Throughout, you will cover important concepts like transform and state, working with text, gradients, and a whole lot more.

By the time you finish this course, you will have a powerful new library at your disposal, and you’ll be able to construct beautiful graphics that users will love.

Computer Graphics in Python and Pycairo

## What are text extents? 

The font size gives us control of the nominal size of the font. The **text extents** tell us the exact size of a particular text string, when rendered with the current font. To be precise, they pinpoint the rectangle around the area that will be marked when we paint the text.

The `Context` and `text_extents` functions return a `Pycairo TextExtents` object (which behaves much like a tuple). Here is an example of this:
```
xbearing, ybearing, width, height, dx, dy = ctx.text_extents('Xyz')
```
The `text_extents` function accepts a string. It calculates the extents of the string and returns the `TextExtents` object, which we unpack into 6 variables. Here is an example of this:

# What are text extents? 

The font size gives us control of the nominal size of the font. The **text extents** tell us the exact size of a particular text string, when rendered with the current font. To be precise, they pinpoint the rectangle around the area that will be marked when we paint the text.

The `Context` and `text_extents` functions return a `Pycairo TextExtents` object (which behaves much like a tuple). Here is an example of this:
```
xbearing, ybearing, width, height, dx, dy = ctx.text_extents('Xyz')
```
The `text_extents` function accepts a string. It calculates the extents of the string and returns the `TextExtents` object, which we unpack into 6 variables. Here is an example of this:

Introduction

Introduction to Vector Graphics

Basic Drawing Operations

Paths and Complex Shapes

Computer Color

Transforms and State

Working with Text

Gradients and Image Fills

Clipping, Masking and Compositing

Surfaces and Output Formats

Integration with Other Libraries

Conclusion

Text Extents

What are text extents?