Building Polyscope as a shared library on Windows

[P4T0U]

On Windows, I managed to build polyscope as a shared library with a couple of changes:

1. Export all symbols for polyscope

--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -374,4 +374,7 @@
 set_target_properties(polyscope PROPERTIES POSITION_INDEPENDENT_CODE TRUE)
 add_definitions(-DNOMINMAX)
+set_target_properties(polyscope PROPERTIES
+  WINDOWS_EXPORT_ALL_SYMBOLS ON
+)
 
 # Include settings

2. Force imgui as static. Again, it would search for a .lib file but no symbols are exported.

--- a/deps/imgui/CMakeLists.txt
+++ b/deps/imgui/CMakeLists.txt
@@ -63,5 +63,5 @@
 
   add_library(
-          imgui
+          imgui STATIC
           ${SRCS}
           )

Alternative: Export all symbols like 1.

3. Force stb as static. Otherwise, it would search for a non-existent .lib file because no symbols are exported.

--- a/deps/stb/CMakeLists.txt
+++ b/deps/stb/CMakeLists.txt
@@ -1,5 +1,5 @@
 # Create a library for the viewer code
 add_library(
-    stb
+    stb STATIC
     stb_impl.cpp
 )

I tried exporting all symbols but it did not work. I would get missing symbols:

[build] screenshot.cpp.obj : error LNK2001: unresolved external symbol "int stbi_write_png_compression_level" (?stbi_write_png_compression_level@@3HA)

4. Tell glm to not build a library. It is header-only anyway:

set(GLM_BUILD_LIBRARY OFF CACHE BOOL "Use GLM as header-only" FORCE)

It is not optimal to export all symbols on Windows, but it works. Dropping this here for others to use.

Open to make a PR but I would rather figure out the approved method first 😄