Installation instructions seem out of date

[mattmazzola]

The installation instructions explain to clone the detectron2 repo and install from the clone

git clone https://github.com/facebookresearch/detectron2.git
cd detectron2
git checkout cc87e7ec
pip install -e .

However, detectron2 is already cloned inside the GRiT repo as third_party/CenterNet2 and pip install -e . should be run from there.

Perhaps the instructions were written before the library was included

Maybe install instructions should be something like this:

conda create --name grit python=3.8 -y
conda activate grit
pip install torch==1.9.0+cu111 torchvision==0.10.0+cu111 torchaudio==0.9.0 -f https://download.pytorch.org/whl/torch_stable.html

cd ..
git clone https://github.com/JialianW/GRiT.git
cd GRiT
pip install -r requirements.txt

cd third_party/CenterNet2
git checkout cc87e7ec
pip install -e .

If PR #16 is merged then installation is automated and this may become obsolete

[JialianW]

Thank you so much for diving into this. The original installation instruction is actually what we used, which should be correct. We git clone the detectron2 and checkout to cc87e7ec. It indeed raise confusion that there is another detectron2 repo already contained in the project. That detectron2 repo came from the Centernet project, and we did not use that detectron2 repo. We simply copied the Centernet project under third_party so we didn't remove that detectron2 yet.