feat(screenshot): new rpc

missing unit tests

Author: JulienChampagnol

src/opengeodeweb_viewer/rpc/schemas/take_screenshot.json

@@ -0,0 +1,7 @@
+{
+    "rpc": "screenshot",
+    "type": "object",
+    "properties": {},
+    "required": [],
+    "additionalProperties": false
+  }

src/opengeodeweb_viewer/vtk_protocol.py

@@ -1,10 +1,19 @@
+# Standard library imports
 import json
 import os
+
+# Third party imports
+import vtk
 from vtk.web import protocols as vtk_protocols
+from vtkmodules.vtkIOImage import vtkPNGWriter
+from vtkmodules.vtkRenderingCore import (vtkWindowToImageFilter)
 from wslink import register as exportRpc
-import vtk
+
+# Local application imports
 from .function import validate_schemas
 
+
+
 schemas = os.path.join(os.path.dirname(__file__), "rpc/schemas")
 
 with open(os.path.join(schemas, "create_visualization.json"), "r") as file:
@@ -35,6 +44,8 @@
     set_color_json = json.load(file)
 with open(os.path.join(schemas, "set_vertex_attribute.json"), "r") as file:
     set_vertex_attribute_json = json.load(file)
+with open(os.path.join(schemas, "take_screenshot.json"), "r") as file:
+    take_screenshot_json = json.load(file)
 
 
 class VtkView(vtk_protocols.vtkWebProtocol):
@@ -271,6 +282,22 @@ def setVertexAttribute(self, params):
         mapper.SetScalarModeToUsePointFieldData()
         self.render()
 
+    @exportRpc(take_screenshot_json["rpc"])
+    def takeScreenshot(self, params):
+        validate_schemas(params, take_screenshot_json)
+        print(f"{params=}", flush=True)
+        renderWindow = self.getView("-1")
+        w2if = vtkWindowToImageFilter()
+        w2if.SetInput(renderWindow)
+        w2if.SetInputBufferTypeToRGB()
+        w2if.ReadFrontBufferOff()
+        w2if.Update()
+
+        writer = vtkPNGWriter()
+        writer.SetFileName(os.path.join(self.DATA_FOLDER_PATH, 'screenshot.png'))
+        writer.SetInputConnection(w2if.GetOutputPort())
+        writer.Write()
+
     def get_data_base(self):
         return self.getSharedObject("db")