How to change the hotkey for switching selection mode between vertex-edge-face

Switching the selection mode between vertices, edges, and polygons in mesh edit mode is mapped by default to pressing the 1, 2, and 3 keycodes on the keyboard. However, if it is more comfortable to use these hotkeys for other functions, we can change this mapping.

Deselect all with a single pressing of the “a” keycode

Since Blender 2.80 the deselect all function – complete deselection of all objects or geometry – has been switched from a single press of the “a” key to a double “a-a” or a combination of “alt+a” keycodes. To return the deselection function to a single “a” press, we can edit the settings of the selection operators. Or, since Blender 2.81, a special checkbox is provided for this in the keyboard shortcuts settings.

  • Open the “Preferences” window
  • Switch to the “KeyMap” section
  • Turn on the “Select All Toggles” checkbox in the “Preferences” subsection
  • Save the settings by pressing the “Save Preferences” button in the upper right corner of the window.

Now the selection of all objects/geometry and their total deselection will be performed by pressing the single “a” key.

How to get the render pixels coordinates in compositing

When fine-tuning the finished render in “Compositing”, sometimes it is necessary to refer to the pixels coordinates of the processed image, for example, to apply effects distributed over the entire width or height of the image.

We can get the distribution factor of coordinates along with the height or width of the rendered image using texture nodes.

Using the FileBrowser interface window to opening and saving files

In scripts and add-ons for importing-exporting files with formats that are not supported in Blender by default, we must give the user an ability to select files using the “FileBrowser” interface.

To open the file browser window, and after the user selects the necessary file, to return the path to it, we need to use the “ImportHelper” and the “ExportHelper” classes.

How to rotate objects through the Blender Python API

For objects rotation, we can use the “rotation_euler” property. This property is a list of three items, each of them corresponds to the rotation angle around the X, Y, and Z-axis. The otation_euler[0] contains the rotation angle around the X-axis, rotation_euler[1] – around the Y-axis, and rotation_euler[2] – around the Z-axis. To rotate an object we must set a rotation angle to the appropriate field of the property.

For example, to rotate an active object around the X-axis to the 90 degrees angle we must execute the following command:

math.radians is used to convert degrees to radians.

How to switch between flat and smooth shading through the Blender Python API

The flat/smooth shading mode is regulated through the “use_smooth” property of each polygon of the mesh.

To enable smooth shading we need to set the “use_smooth” property of each mesh polygon to “True”.

For active object:

To enable flat shading – set the “use_smooth” property of each polygon to “False”.

To make new shading mode visible – force update mesh data: