Grass breaking frame rate :(

Game Engine Game Engine Support and Discussion
1

Hello again, I was trying to create a natural-themed game scene, but when I added the grass, the frame-rate plummeted a lot, I think I am problem with the number of objects in the scene. Does anyone know a way to fix this? Am I doing something wrong?

Project made at UPBGE

Download .blend:

2

Maybe just merge the objects together: Faster to render 1 object with 10K faces than it is to render 10K objects with 1 face.

3 Likes
3

Use custom LOD (when the player is at a certain distance, turn grass objects invisible & visible when the player is near)

Also set-up occluder objects when possible.

4

Merge the objects, batch them together or maybe try geometry instancing from material options.
I’m not sure about the latter as it causes an instant CTD on my computer, so I haven’t really tested it

2 Likes
5

I can’t use this code to group objects added durante o gameplay :frowning:

6

how i can use “merge(objects)”? I try and no work. (sorry my english)

7

select a few grass objects and hit ctrl+j

1 Like
8

i’m try this code, but him return a erro in console: “Error: object “Grass_merge” already used in a batch group”

from bge import logic as g
from bge import types as t
import math
import random

cont = g.getCurrentController()
scene = g.getCurrentScene()
own = cont.owner

mesh = own.meshes[0]


for index in range( mesh.getVertexArrayLength(0) ):
    vertex = mesh.getVertex( 0, index )
    pos = own.worldTransform * vertex.XYZ
    porcentagem = 0.05
    if random.random() < porcentagem:
        lst = scene.addObject("Grass")
        lst.worldPosition = own.worldTransform * vertex.XYZ
        lst.localScale = [random.uniform(0.5, 1.0), random.uniform(0.5, 1.1) ,random.uniform(0.5, 1.1)]
        
        ori = lst.localOrientation.to_euler()
        ori[2] = math.radians(random.uniform(0.0, 360.0))
        lst.localOrientation = ori.to_matrix()
        
        all_grass = [obj for obj in scene.objects if obj.name.startswith("Grass")]
    
        
    print(index, mesh.getVertexArrayLength(0)-1)
    
    if index >= (mesh.getVertexArrayLength(0)-1):
            b_g = t.KX_BatchGroup(all_grass)
            b_g.merge(["Grass_merge"])
            print(scene.objects)
9

AFAIK initializing a batch group with a list of objects automatically merges them.

from bge.logic import getCurrentController
from bge.types import KX_BatchGroup as bgroup
own = getCurrentController().owner

mesh = own.meshes[0]
all_grass = [None for vi in range( mesh.getVertexArrayLength(0) )]

for vi in range( mesh.getVertexArrayLength(0) ):
    vert = mesh.getVertex(0, vi)
    newObj = all_grass[vi] = own.scene.addObject("Grass")    
    newObj.worldPosition = own.worldPosition + vert.getXYZ()

#make sure no item in the list equals None, then make the batch
all_grass = [obj for obj in all_grass if obj]
batch_grass = bgroup(all_grass)

Here’s my test file grass.blend (956.7 KB)

1 Like