2 files changed, 44 insertions, 12 deletions
diff --git a/modules/devices.py b/modules/devices.py
index b58776d8..00a00b18 100644
--- a/modules/devices.py
+++ b/modules/devices.py
@@ -71,14 +71,17 @@ def enable_tf32():
         torch.backends.cudnn.allow_tf32 = True
 
 
-
 errors.run(enable_tf32, "Enabling TF32")
 
-cpu = torch.device("cpu")
-device = device_interrogate = device_gfpgan = device_esrgan = device_codeformer = None
-dtype = torch.float16
-dtype_vae = torch.float16
-dtype_unet = torch.float16
+cpu: torch.device = torch.device("cpu")
+device: torch.device = None
+device_interrogate: torch.device = None
+device_gfpgan: torch.device = None
+device_esrgan: torch.device = None
+device_codeformer: torch.device = None
+dtype: torch.dtype = torch.float16
+dtype_vae: torch.dtype = torch.float16
+dtype_unet: torch.dtype = torch.float16
 unet_needs_upcast = False
 
 
@@ -94,6 +97,10 @@ nv_rng = None
 
 
 def randn(seed, shape):
+    """Generate a tensor with random numbers from a normal distribution using seed.
+
+    Uses the seed parameter to set the global torch seed; to generate more with that seed, use randn_like/randn_without_seed."""
+
     from modules.shared import opts
 
     manual_seed(seed)
@@ -107,7 +114,27 @@ def randn(seed, shape):
     return torch.randn(shape, device=device)
 
 
+def randn_local(seed, shape):
+    """Generate a tensor with random numbers from a normal distribution using seed.
+
+    Does not change the global random number generator. You can only generate the seed's first tensor using this function."""
+
+    from modules.shared import opts
+
+    if opts.randn_source == "NV":
+        rng = rng_philox.Generator(seed)
+        return torch.asarray(rng.randn(shape), device=device)
+
+    local_device = cpu if opts.randn_source == "CPU" or device.type == 'mps' else device
+    local_generator = torch.Generator(local_device).manual_seed(int(seed))
+    return torch.randn(shape, device=local_device, generator=local_generator).to(device)
+
+
 def randn_like(x):
+    """Generate a tensor with random numbers from a normal distribution using the previously initialized genrator.
+
+    Use either randn() or manual_seed() to initialize the generator."""
+
     from modules.shared import opts
 
     if opts.randn_source == "NV":
@@ -120,6 +147,10 @@ def randn_like(x):
 
 
 def randn_without_seed(shape):
+    """Generate a tensor with random numbers from a normal distribution using the previously initialized genrator.
+
+    Use either randn() or manual_seed() to initialize the generator."""
+
     from modules.shared import opts
 
     if opts.randn_source == "NV":
@@ -132,6 +163,7 @@ def randn_without_seed(shape):
 
 
 def manual_seed(seed):
+    """Set up a global random number generator using the specified seed."""
     from modules.shared import opts
 
     if opts.randn_source == "NV":
diff --git a/modules/sd_samplers_common.py b/modules/sd_samplers_common.py
index 763829f1..5deda761 100644
--- a/modules/sd_samplers_common.py
+++ b/modules/sd_samplers_common.py
@@ -2,10 +2,8 @@ from collections import namedtuple
 import numpy as np
 import torch
 from PIL import Image
-from modules import devices, processing, images, sd_vae_approx, sd_samplers, sd_vae_taesd
-
+from modules import devices, processing, images, sd_vae_approx, sd_samplers, sd_vae_taesd, shared
 from modules.shared import opts, state
-import modules.shared as shared
 
 SamplerData = namedtuple('SamplerData', ['name', 'constructor', 'aliases', 'options'])
 
@@ -85,11 +83,13 @@ class InterruptedException(BaseException):
     pass
 
 
-if opts.randn_source == "CPU":
+def replace_torchsde_browinan():
     import torchsde._brownian.brownian_interval
 
     def torchsde_randn(size, dtype, device, seed):
-        generator = torch.Generator(devices.cpu).manual_seed(int(seed))
-        return torch.randn(size, dtype=dtype, device=devices.cpu, generator=generator).to(device)
+        return devices.randn_local(seed, size).to(device=device, dtype=dtype)
 
     torchsde._brownian.brownian_interval._randn = torchsde_randn
+
+
+replace_torchsde_browinan()