Instantiating multiple plane using Graphics.DrawMeshInstancedIndirect (the position of the instances is adjusted in the vertex shader).

I retrieve the matrix transformation from the buffer. With this TRS matrix, I can retrieve the origin and the up axis for each instance. (return _sharedVisibleBuffer[id].transform;).

Multiplying vertex postion by the TRS matrix.

To avoid to render both sides, I force each instance to face the camera. To do this, I calculate the angle and apply a rotation around the UP axis.

To avoid rotation repetition, I sample a texture that adds or subtracts a few degrees from the calculated rotation angle.

To simulate wind, I sample the same texture four times using different UV and time settings. Each channel of the RGBA texture contains a different noise pattern to create a natural variation in the wind.

Using the results of the various texture samples as input for the rotation angle. The rotation axis is defined by a parameter in the material (it represents the wind direction).

I use a texture flipbook to create different shapes of grass and flowers.

To add some interactivity, I use a flow map texture, which allows the grass to bend when an object or player walks over it.
To create the texture, I paint over the object's position in a render texture that is passed to multiple shaders via Graphics.Blit.

Blur pass: This shader blur a texture by adding the value of each pixel to its neighborings pixel.

Flowmap pass: This shader compares the value of a pixel to those of its neighbors and calculates the local variation (approximation of the partial derivatives), yielding a 2D direction that represents the slope along the x and y axis.

To create the lit effects on the grass, I need to calculate the vertex normals based on the changes in vertex positions.

Once the normal vectors are fixed, I can calculate the sun impact using the dotNL.

I also add a horizon effect when the sun is low in the sky. It looks like specular lighting, but it’s the same effect as dotNL with different settings.

I use an ID in my buffer that specifies whether it's a blade of grass or a flower. For the lit of the flowers, I use two arrays that contain the Hue color information.

To determine if an instance is a flower or a blade of grass, I use a texture that contains this informations.
(black = grass blade, red = no instance, blue = flower 1, green = flower 2).

I use an ID in my buffer that specifies whether it's a blade of grass or a flower. For the lighting of the flowers, I use two arrays that contain the color information.

All shader graph.