Fixed wrong/no export issue (#159)

Note: this only works when a SINGLE mesh sequence is present

src/__init__.py

@@ -25,7 +25,7 @@
     "name": "Stop motion OBJ",
     "description": "Import a sequence of OBJ (or STL or PLY or X3D) files and display them each as a single frame of animation. This add-on also supports the .STL, .PLY, and .X3D file formats.",
     "author": "Justin Jensen",
-    "version": (2, 2, 0, "alpha.20"),
+    "version": (2, 2, 0, "alpha.21"),
     "blender": (2, 83, 0),
     "location": "File > Import > Mesh Sequence",
     "warning": "",

src/stop_motion_obj.py

@@ -32,6 +32,7 @@
 forceMeshLoad = False
 loadingSequenceLock = False
 inRenderMode = False
+lockFrameSwitch = False
 
 def alphanumKey(string):
     """ Turn a string into a list of string and number chunks.
@@ -42,6 +43,9 @@ def alphanumKey(string):
 def clamp(value, minVal, maxVal):
     return max(minVal, min(value, maxVal))
 
+def selectOnly(obj):
+    deselectAll()
+    obj.select_set(state=True)
 
 def deselectAll():
     for ob in bpy.context.scene.objects:
@@ -53,8 +57,10 @@ def checkMeshChangesFrameChangePre(scene):
     if inRenderMode == True:
         return
 
+    obj = bpy.context.object
+
     # if the selected object is not a loaded and initialized mesh sequence, return
-    mss = bpy.context.object.mesh_sequence_settings
+    mss = obj.mesh_sequence_settings
     if mss.initialized is False or mss.loaded is False:
         return
 
@@ -68,15 +74,19 @@ def checkMeshChangesFrameChangePre(scene):
         return
 
     # generate the mesh hash for the current mesh (just before the frame switches)
-    meshHashStr = getMeshHashStr(bpy.context.object.data)
+    meshHashStr = getMeshHashStr(obj.data)
 
     # if the generated mesh hash does not match the mesh's stored hash
     # for some reason we also have to check whether the meshHash has not been calculated yet
-    if bpy.context.object.data.meshHash != '' and meshHashStr != bpy.context.object.data.meshHash:
+    if obj.data.meshHash != '' and meshHashStr != obj.data.meshHash:
+        # lock frame switching until we're done exporting (so that we export the correct frame beofre the next one is loaded)
+        global lockFrameSwitch
+        lockFrameSwitch = True
+
         # update the mesh hash
-        bpy.context.object.data.meshHash = meshHashStr
+        obj.data.meshHash = meshHashStr
 
-        #   export this updated mesh
+        # export this updated mesh
         absDir = ''
         if mss.overwriteSrcDir is True:
             # writing over the original meshes
@@ -90,12 +100,21 @@ def checkMeshChangesFrameChangePre(scene):
                 return
 
         filename = os.path.join(absDir, mss.meshNameArray[mss.curVisibleMeshIdx].basename)
+
+        # select only this object so that this object is the only one that will be exported
+        selectOnly(obj)
+
+        # actually export the file
         mss.fileImporter.export(mss.fileFormat, filename)
 
         # show an unobtrusive message that the mesh has been exported
         msg = "Mesh exported: " + filename
         bpy.context.workspace.status_text_set(text=msg)
 
+        # once the export operation has fully finished, unlock importing/changing meshes, then trigger an updateFrame call
+        lockFrameSwitch = False
+        updateFrame(0)
+
 
 def showError(message=""):
     def draw(self, context):
@@ -204,6 +223,10 @@ def lockLoadingSequence(lock):
 # set the frame number for all mesh sequence objects
 @persistent
 def updateFrame(scene):
+    global lockFrameSwitch
+    if lockFrameSwitch is True:
+        # we're not ready to switch frames yet
+        return
     global loadingSequenceLock
     if loadingSequenceLock is False:
         scn = bpy.context.scene
@@ -985,6 +1008,7 @@ def setFrameObjStreamed(obj, frameNum, forceLoad=False, deleteMaterials=False):
     # if we want to load new meshes as needed and it's not already loaded
     if nextMeshProp.inMemory is False and (mss.streamDuringPlayback is True or forceLoad is True):
         importStreamedFile(obj, idx)
+        obj.select_set(state=True)
         if deleteMaterials is True:
             nextMesh = getMeshFromIndex(obj, idx)
             deleteLinkedMeshMaterials(nextMesh)

src/version.py

@@ -2,5 +2,5 @@
 # (major, minor, revision, development)
 # example dev version: (1, 2, 3, "beta.4")
 # example release version: (2, 3, 4)
-currentScriptVersion = (2, 2, 0, "alpha.20")
+currentScriptVersion = (2, 2, 0, "alpha.21")
 legacyScriptVersion = (2, 0, 2, "legacy")