Utils organization (#3624)

* Util organization

* Renaming utils

* Updating example scripts

* utils not needed in workflow_example

apps/pythonapi/examples/annotation_example.py

@@ -6,7 +6,8 @@
 #
 # %%
 import example_utils
-from vapor import session, renderer, dataset, camera, utils
+from vapor import session, renderer, dataset, camera
+from vapor.utils import histogram
 
 ses = session.Session()
 data = example_utils.OpenExampleDataset(ses)
@@ -59,14 +60,14 @@
 # ## MatPlotLib Histograms
 #
 # %%
-utils.ShowMatPlotLibHistogram(ses, ren)
+histogram.ShowMatPlotLibHistogram(ses, ren)
 
 # %% [md]
 # ---
 # You can customize the histograms as you would `matplotlib.pyplot.hist`
 #
 # %%
-plt = utils.GetMatPlotLibHistogram(ses, ren, color ="red")
+plt = histogram.GetMatPlotLibHistogram(ses, ren, color ="red")
 plt.xlabel("X-Axis")
 plt.ylabel("Y-Axis")
 plt.title("Title\n", fontweight="bold")

apps/pythonapi/examples/transfer_function_example.py

@@ -4,7 +4,8 @@
 #
 # %%
 import example_utils
-from vapor import session, renderer, dataset, camera, utils, transferfunction
+from vapor import session, renderer, dataset, camera, transferfunction
+from vapor.utils import histogram
 
 ses = session.Session()
 data = example_utils.OpenExampleDataset(ses)
@@ -20,7 +21,7 @@
 # Before we adjust the opacity map of the TF, we get a histogram to help us determine what we want to hide.
 #
 # %%
-utils.ShowMatPlotLibHistogram(ses, ren)
+histogram.ShowMatPlotLibHistogram(ses, ren)
 
 # %% [md]
 #
@@ -35,7 +36,7 @@
 # We can get the matplotlib histogram plot and add our opacity map to it to compare.
 #
 # %%
-plt = utils.GetMatPlotLibHistogram(ses, ren)
+plt = histogram.GetMatPlotLibHistogram(ses, ren)
 plt.plot(*zip(*opacities))
 plt.show()
 

apps/pythonapi/examples/workflow_example.py

@@ -8,7 +8,7 @@
 #
 # %%
 import example_utils
-from vapor import session, renderer, dataset, camera, utils
+from vapor import session, renderer, dataset, camera
 
 # %%
 ses = session.Session()

apps/pythonapi/vapor/utils.py → apps/pythonapi/vapor/utils/histogram.py

@@ -1,4 +1,4 @@
-from .session import *
+from ..session import *
 import matplotlib.pyplot as plt
 import numpy as np
 import functools

apps/pythonapi/vapor/utils/keyframing.py

@@ -0,0 +1,92 @@
+from ..session import Session
+from ..animation import Animation
+
+def animate_camera_keyframes(session_paths, steps = None):
+    """
+    Given a list of file paths to sessions with different camera angles, returns an
+    animation that performs keyframing with linear interpolation between those camera angles.
+    """
+    # Default for steps
+    if steps == None:
+        steps = [30] * (len(session_paths) - 1)
+
+    # Parameter checks
+    if len(session_paths) - len(steps) != 1:
+        raise TypeError(f"With {len(session_paths)} keyframes given, 'steps' should be " +
+                        f"length {len(session_paths) - 1} (currently {len(steps)})")
+
+    # Load key frames as sessions
+    key_frames = []
+    for path in session_paths:
+        ses = Session()
+        ses.Load(path)
+        key_frames.append(ses)
+
+    # Visualization will use renderers from first session in list. Other sessions are only for camera angles
+    primary_session = key_frames[0]
+    anim = Animation(primary_session)
+    cam = primary_session.GetCamera()
+    total_frames = sum(steps)
+
+    # Interpolate camera information between each key frame
+    n = 0
+    for i in range(len(key_frames) - 1):
+        start = key_frames[i]
+        end = key_frames[i+1]
+        frames = steps[i]
+        # Get starting information
+        cam1 = start.GetCamera()
+        dir1 = cam1.GetDirection()
+        pos1 = cam1.GetPosition()
+        up1 = cam1.GetUp()
+
+        # Get ending information
+        cam2 = end.GetCamera()
+        dir2 = cam2.GetDirection()
+        pos2 = cam2.GetPosition()
+        up2 = cam2.GetUp()
+
+        # Difference between camera positions on each axis
+        dPositionX  = (pos2[0] - pos1[0])
+        dPositionY  = (pos2[1] - pos1[1])
+        dPositionZ  = (pos2[2] - pos1[2])
+
+        # Difference between camera direction vectors on each axis
+        dDirectionX = (dir2[0] - dir1[0])
+        dDirectionY = (dir2[1] - dir1[1])
+        dDirectionZ = (dir2[2] - dir1[2])
+
+        # Difference between camera up vectors on each axis
+        dUpX        = (up2[0] - up1[0])
+        dUpY        = (up2[1] - up1[1])
+        dUpZ        = (up2[2] - up1[2])
+
+        # Linear interpolation between start and end
+        for j in range(frames):
+            position = [
+                pos1[0]+dPositionX*j/frames,
+                pos1[1]+dPositionY*j/frames,
+                pos1[2]+dPositionZ*j/frames
+            ]
+            cam.SetPosition( position )
+
+            direction = [
+                dir1[0]+dDirectionX*j/frames,
+                dir1[1]+dDirectionY*j/frames,
+                dir1[2]+dDirectionZ*j/frames
+            ]
+            cam.SetDirection( direction )
+
+            up = [
+                up1[0]+dUpX*j/frames,
+                up1[1]+dUpY*j/frames,
+                up1[2]+dUpZ*j/frames
+            ]
+            cam.SetUp( up )
+            anim.CaptureFrame()
+
+            # Print status
+            print(f"Rendering Animation [{'#'*round((j+n)*40/total_frames)}{' '*round(40-((j+n)*40/total_frames))}] {(j+1+n)*100/total_frames:.0f}%", end="\r")
+        n += steps[i]
+    return anim
+