Gain insights into computer graphics with Python's Pycairo library. Learn about pixel vs. vector graphics, create complex shapes, work with transforms, text, gradients, and more for VR and game development.

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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

Pycairo can be integrated with several other Python libraries to extend its capabilities. We will look at some examples in this section.


# How does Pycairo store image data?

Several of the techniques for transferring image data make use of the `ImageSurface` methods: `create_for_data` and `get_data`.

**`create_for_data`** accepts a writable buffer or `memoryview` object that contains image data. It also requires the format,such as the `cairo.Format class=RGB24` format, and the image `width` and `height`.

```
surface = cairo.ImageSurface.create_for_data(data, format, width, height, [stride])
```

This creates a new `ImageSurface`, which contains the image contained in the data. `Stride` is an optional integer that indicates the number of bytes between the start of each row in the data buffer. It can be ignored and the function will calculate the value based on the image width.

The `get_data` function returns a `memoryview` object, which contains image data from the `ImageSurface`:

```
data = surface.get_data()
```
Over here, the `surface` is an existing `ImageSurface`.

This is a playground where we have made a `surface` and a red rectangle is drawn on it. We will call the `get_data` function, followed by the `create_for_data` function to create a new surface, `surface2`, with a different format (RGB24).

Learn about how Pycairo stores image data.

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

Storing Image Data

How does Pycairo store image data?