Not a precise copy of the texture Image

## Bevy version

---0.13.2---

# Genral information

AdapterInfo { name: "NVIDIA GeForce GTX 1070 Ti", vendor: 4318, device: 7042, device_type: DiscreteGpu, driver: "NVIDIA", driver_info: "536.23", backend: Vulkan }

# The problem

the problem is not a precise copy of the texture Image.

I have made Mesh and Image for building PbrBundle.

When rendering it, it seems weird because some "line" appears.

It is caused because it copies from the image "unrelated" part (just a bit above) part too

It is a big problem when the mesh has transparent parts.

## Suggestion

I think it can be "fixed" by implementing 3D Images for standard material or having some index like UV but it should have a hole number that matches the width of the image and height.

Start by reproducing the reported rendering problem with the Bevy 0.13.2 PbrBundle built from the mentioned Mesh and Image, using the provided screenshots as the expected context. Investigate texture sampling around the Image and standard material; done means the mesh samples only the intended texture area, including when transparent parts are present.

Written by the indexing model from the issue text.