Ensure that wgpu is compatible both with imgui 1.6.0 and older (#649)

* Ensure that wgpu is compatible both with imgui 1.6.0 and older

* Use try execpt. Release pin

pyproject.toml

@@ -15,7 +15,7 @@ dependencies = ["cffi>=1.15.0", "rubicon-objc>=0.4.1; sys_platform == 'darwin'"]
 # For users
 jupyter = ["jupyter_rfb>=0.4.2"]
 glfw = ["glfw>=1.9"]
-imgui = ["imgui-bundle>=1.6.0"]
+imgui = ["imgui-bundle>=1.2.1"]
 # For devs / ci
 build = ["build", "hatchling", "requests", "twine"]
 codegen = ["pytest", "numpy", "ruff"]

wgpu/utils/imgui/imgui_renderer.py

@@ -43,12 +43,26 @@ class ImguiRenderer:
         "Tab": imgui.Key.tab,
     }
 
-    KEY_MAP_MOD = {
-        "Shift": imgui.Key.mod_shift,
-        "Control": imgui.Key.mod_ctrl,
-        "Alt": imgui.Key.mod_alt,
-        "Meta": imgui.Key.mod_super,
-    }
+    # imgui changed its API between 1.5.2 and 1.6.0
+    # But as of Dec 1, 2024, it is too early for us to force
+    # users to use one specific version.
+    # So we will support both versions for now with this small shim
+    try:
+        # Version 1.6.0 and above
+        KEY_MAP_MOD = {
+            "Shift": imgui.Key.mod_shift,
+            "Control": imgui.Key.mod_ctrl,
+            "Alt": imgui.Key.mod_alt,
+            "Meta": imgui.Key.mod_super,
+        }
+    except AttributeError:
+        # Version 1.2.1 to 1.5.2
+        KEY_MAP_MOD = {
+            "Shift": imgui.Key.im_gui_mod_shift,
+            "Control": imgui.Key.im_gui_mod_ctrl,
+            "Alt": imgui.Key.im_gui_mod_alt,
+            "Meta": imgui.Key.im_gui_mod_super,
+        }
 
     def __init__(
         self, device, canvas: wgpu.gui.WgpuCanvasBase, render_target_format=None