Textures

Introduction

The arcade.Texture type is how arcade normally interacts with images either loaded from disk or created manually. This is basically a wrapper for PIL/Pillow images including detection for hit box data using pymunk depending on the selected hit box algorithm. These texture objects are in other words responsible to provide raw RGBA pixel data to OpenGL and hit box geometry to the sprite engine.

There is another texture type in arcade in the lower level OpenGL api: arcade.gl.Texture. This represents and actual OpenGL texture and should only be used when dealing with the low level rendering api arcade.gl.

Textures can be created/loaded before or after the window is created because they don’t interact with OpenGL directly.

Texture Uniqueness

When a texture is created a name is required. This should be a unique string. If two more more textures have the same name we will run into trouble. When loading textures the absolute path to the file is used as part of the name including vertical/horizontal/diagonal, size and other parameter for a truly unique name.

When loading texture through arcade the name of the texture will be the absolute path to the image and various parameters such as size, flipping, xy position etc.

Also remember that the texture class do hit box detection with pymunk by looking at the raw pixel data. This means for example a texture with different flipping will be loaded multiple times (or fetched from cache) because we rely in the transformed pixel data to get the hit box.

Texture Cache

Arcade is caching texture instances based on the name attribute to significantly speed up loading times.

# The texture will only be loaded during the first sprite creation
tex_name = "path/to/sprite.png"
sprite_1 = arcade.Sprite(tex_name)
sprite_2 = arcade.Sprite(tex_name)
sprite_3 = arcade.Sprite(tex_name)
# Will be loaded and cached because we need fresh pixel data for hit box detection
sprite_4 = arcade.Sprite(tex_name, flipped_vertically=True)
# Fetched from cache
sprite_5 = arcade.Sprite(tex_name, flipped_vertically=True)

The above also applies when using arcade.load_texture() or other texture loading functions.

Arcade’s texture cache can be cleared using arcade.cleanup_texture_cache().

Custom Textures

We can manually create textures by creating PIL/Pillow images. How this is done is entirely up to you. Using the drawing functionality of Pillow or simply providing raw pixel data from another library/source into a Pillow image. A random example is getting raw pixel data from matplotlib.

# Create a image from raw pixel data from some source
image = PIL.Image.frombuffer(raw_data)

# NOTE: Also make sure you use a sane hit_box_algorithm
texture = arcade.Texture("unique_name", image, hit_box_algorithm=...)

Again, how you create the image is up to you. There are many possibilities with Pillow.