Restore LV_OSMESA standalone build, add LV_OSMESA_EXT

Since standalone OSMesa builds are still being used, we now enable all
the new functionality for supporting osmesa as a fallback for other
window types with LV_OSMESA_EXT=1 instead.
This should provide full backwards compatibility.

Author: OKaluza

.github/workflows/osmesa_deploy.yaml

@@ -22,7 +22,7 @@ jobs:
         LV_INC_DIRS=${HOME}/include
         LV_MIN_DEPS=1
         LV_PACKAGE=lavavu-osmesa
-        LV_OSMESA=1
+        LV_OSMESA_EXT=1
         LV_ECHO_FAIL=1
         LV_ARGS="-v"
       CIBW_BEFORE_BUILD_LINUX: >

.github/workflows/testing.yaml

@@ -34,7 +34,7 @@ jobs:
         run: python -m pip install -r requirements.txt
       - name: Build/install
         env:
-          LV_OSMESA: 1
+          LV_OSMESA_EXT: 1
         run: python -m pip install .
       - name: Run headless test
         env:

lavavu/LavaVuPython.py

@@ -6,10 +6,13 @@
 
 from sys import version_info as _swig_python_version_info
 
-import os
-if 'osmesa' in os.environ.get('LV_CONTEXT', ''):
-    from osmesa import _LavaVuPython
-else:
+try:
+    import os
+    if 'osmesa' in os.environ.get('LV_CONTEXT', ''):
+        from osmesa import _LavaVuPython
+    else:
+        import _LavaVuPython
+except ImportError as e:
     import _LavaVuPython
 
 

lavavu/lavavu.py

@@ -88,11 +88,11 @@
 except (ImportError) as e:
     av = None
 
-#import swig module
-context = os.environ.get("LV_CONTEXT", "").strip()
+#Prepare to import swig module
 if platform.system() == 'Linux':
     #Default context requires DISPLAY set for X11
     display = os.environ.get("DISPLAY", "").strip()
+    context = os.environ.get("LV_CONTEXT", "").strip()
     if len(context) == 0: context = 'default'
     if context != 'default' or len(display) == 0:
         if context != 'osmesa':
@@ -102,13 +102,10 @@
                 context = 'moderngl'
             except Exception as e:
                 context = 'osmesa'
-            os.environ['LV_CONTEXT'] = context
+    os.environ['LV_CONTEXT'] = context
 
-#Default module if none already loaded
-try:
-    LavaVuPython
-except:
-    import LavaVuPython
+#Import swig module
+import LavaVuPython
 
 version = LavaVuPython.version
 server_ports = []
@@ -3102,7 +3099,8 @@ def gl(self):
         """
         Return GL version string
         """
-        return self.app.gl_version()
+        ctx = os.environ.get("LV_CONTEXT", "")
+        return f"[{ctx}] : {self.app.gl_version()}"
 
     @property
     def port(self):

setup.py

@@ -376,13 +376,8 @@ def check_libraries(libraries, headers, extra_lib_dirs=[], extra_inc_dirs=[]):
 
         if P == 'Linux':
             #Linux GLFW, X11, EGL or OSMesa
-            #EGL and OSMesa are built as optional extra modules
-            '''
-            if find_library('OpenGL') and find_library('EGL') and check_libraries(['OpenGL', 'EGL'], ['GL/gl.h', 'EGL/egl.h']):
-            ''';
-
-            #OSMesa built as optional extra module
-            if ("LV_OSMESA" in os.environ and find_library('OSMesa')
+            #OSMesa can be built as optional extra module
+            if ("LV_OSMESA_EXT" in os.environ and find_library('OSMesa')
             and check_libraries(['OSMesa'], ['GL/osmesa.h'])):
                 #OSMesa for software rendered offscreen OpenGL, build as additional extension
                 ex = Extension('lavavu.osmesa._LavaVuPython',
@@ -397,8 +392,13 @@ def check_libraries(libraries, headers, extra_lib_dirs=[], extra_inc_dirs=[]):
                                 sources = srcs)
                 extensions.append(ex)
 
-            #Main extension - use X11 or GLFW
-            if ("LV_EGL" in os.environ and find_library('OpenGL') and find_library('EGL')
+            #Main extension - use X11 or GLFW (or OSMesa)
+            if ("LV_OSMESA" in os.environ and find_library('OSMesa')
+            and check_libraries(['OSMesa'], ['GL/osmesa.h'])):
+                #OSMesa for software rendered offscreen OpenGL
+                defines += [('HAVE_OSMESA', '1')]
+                libs += ['OSMesa']
+            elif ("LV_EGL" in os.environ and find_library('OpenGL') and find_library('EGL')
             and check_libraries(['OpenGL', 'EGL'], ['GL/gl.h', 'EGL/egl.h'])):
                 #EGL for offscreen OpenGL without X11/GLX - works with NVidia and latest Mesa
                 defines += [('HAVE_EGL', '1')]

src/LavaVuPython.i

@@ -3,10 +3,13 @@
 **~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*/
 %define MODULEIMPORT
 "
-import os
-if 'osmesa' in os.environ.get('LV_CONTEXT', ''):
-    from osmesa import $module
-else:
+try:
+    import os
+    if 'osmesa' in os.environ.get('LV_CONTEXT', ''):
+        from osmesa import $module
+    else:
+        import $module
+except ImportError as e:
     import $module
 "
 %enddef