# Blender for cv
This library helps CV researchers to generate data using blender.
## Library tutorial
This repo provides a simple package `blcv` that can put models into scene and get images from different viewpoints.
### Install
You can use `pip install blcv ` to install the package.
Note that we should use `blcv` in Blender's bundled Python, so you need to install the package in Blender's Python environment.
Use the following commands:
`$ cd /blender-path/2.xx/python/bin/`
`/blender-path/2.xx/python/bin$ python.exe get-pip.py`
`/blender-path/2.xx/python/bin$ python.exe -m pip install blcv`
If you encounter more problems installing blcv in Blender environment, you can refer to this [answer]( https://blender.stackovernet.com/cn/q/14721 ).
If there is problems using `pip`, you can simply clone this repo, and use the files in `blcv` folder.
### Functions
blcv
- call_blender(render_code, blender_executable_path, blank_blend_file_path, io_redirect='', background=True): activate Blender and call the script
- render_code: directory to Blender script
- blender_executable_path: directory to Blender.exe
- blank_blend_file_path: Blender file
- io_redirect: redirect the output into a file, use '' to show the output in command lines
- background: whether run the Blender in background, default as 'True'
blcv.tools
- BcObject: operate an existed object in the scene
- init(self, id): input the name of the object
- destroy(self): delete the object
- set_loc(self, x, y, z): set the object's location
- get_loc(self, x, y, z): get the object's location
- set_rot(self, x, y, z, w=None, mode='XYZ'): set the object's rotation; the mode includes 'AXIS_ANGLE', 'QUATERNION' and 'XYZ'
- get_rot(self, mode='XYZ', w=None): set the object's rotation; the mode includes 'AXIS_ANGLE', 'QUATERNION' and 'XYZ'
- set_scale(self, x, y, z): set the object's scale
- get_scale(self, ): get the object's scale
- BcCamera(BcObject): operate an camera in the scene
- init(self, id): input the name of the camera
- set_camera_to_center(self, dist, azimuth_deg, elevation_deg, theta_deg): given the camera's rotation, set the camera in the position towards the center point [0, 0, 0]
- BcScene:
- init(self)
- set_render_mode(self, mode): set the background mode
- get_img(self, filepath): save image crop in filaepath
- import_obj(shape_file): import a new model into the scene and return its name
### Demo
You can modify the configurations and run `start_blender.py` to call `blender_script` in Blender.
The demo generates airplane images from circle viewpoints using the models in `examples` folder, the results will be saved in `images` folder.
### Contact
If you have any questions or encounter any problems, feel free to contact me by sarahwei0210@gmail.com.
