remove unused sampler, normalize predicted normals from network

nerfstudio/fields/dreamfusion_field.py

@@ -43,6 +43,7 @@ from nerfstudio.field_components.spatial_distortions import (
     SpatialDistortion,
 )
 from nerfstudio.fields.base_field import Field
+from nerfstudio.utils import colormaps, colors, math
 
 try:
     import tinycudann as tcnn
@@ -208,7 +209,7 @@ class DreamFusionField(Field):
         pred_normals_inp = torch.cat([positions_flat, density_embedding.view(-1, self.geo_feat_dim)], dim=-1)
 
         x = self.mlp_pred_normals(pred_normals_inp).view(*outputs_shape, -1).to(directions)
-        outputs[FieldHeadNames.PRED_NORMALS] = self.field_head_pred_normals(x)
+        outputs[FieldHeadNames.PRED_NORMALS] = math.safe_normalize(self.field_head_pred_normals(x))
 
         h = density_embedding.view(-1, self.geo_feat_dim)
 

nerfstudio/models/dreamfusion.py

@@ -149,7 +149,6 @@ class DreamFusionModel(Model):
 
         # samplers
         self.sampler_uniform = UniformSampler(num_samples=self.num_samples, single_jitter=True)
-        self.sampler_pdf = PDFSampler(num_samples=self.num_samples // 2, single_jitter=True)
 
         # renderers
         self.renderer_rgb = RGBRenderer(background_color=colors.WHITE)