[vlc-devel] [PATCH 1/2] interop_dxva2: load extension from vlc_gl_t

[Alexandre Janniaux]

The only users of those extensions are interop modules, so only
interop_dxva2 for extension related to WGL integration.

By moving the loading of those extension to the interop, we can have
them working even when the OpenGL platform context is provided by the
vglmem (vgl.c) module callbacks, allowing hardware acceleration even
when using the libvlc OpenGL callbacks.

Filters would likely be using only OpenGL extensions that are already
available, but could be using the same mechanism in the worst-case
scenario.

Fixes #25234
---
 modules/video_output/Makefile.am            |  2 +-
 modules/video_output/opengl/interop_dxva2.c | 30 ++++++++++++++++++---
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/modules/video_output/Makefile.am b/modules/video_output/Makefile.am
index 375da4b28d..86ed27d85d 100644
--- a/modules/video_output/Makefile.am
+++ b/modules/video_output/Makefile.am
@@ -121,7 +121,7 @@ libdirect3d9_plugin_la_LDFLAGS = $(AM_LDFLAGS) -rpath '$(voutdir)'
 libglinterop_dxva2_plugin_la_SOURCES = video_output/opengl/interop_dxva2.c \
 	video_output/opengl/interop.h
 libglinterop_dxva2_plugin_la_CFLAGS = $(AM_CFLAGS) $(GL_CFLAGS)
-libglinterop_dxva2_plugin_la_LIBADD = libd3d9_common.la
+libglinterop_dxva2_plugin_la_LIBADD = libd3d9_common.la -lopengl32
 
 if HAVE_WIN32_DESKTOP
 vout_LTLIBRARIES += $(LTLIBdirect3d9)
diff --git a/modules/video_output/opengl/interop_dxva2.c b/modules/video_output/opengl/interop_dxva2.c
index 2b32e93272..225db1d430 100644
--- a/modules/video_output/opengl/interop_dxva2.c
+++ b/modules/video_output/opengl/interop_dxva2.c
@@ -71,6 +71,8 @@ vlc_module_begin ()
 vlc_module_end ()
 
 struct wgl_vt {
+    PFNWGLGETEXTENSIONSSTRINGEXTPROC     GetExtensionsStringEXT;
+    PFNWGLGETEXTENSIONSSTRINGARBPROC     GetExtensionsStringARB;
     PFNWGLDXSETRESOURCESHAREHANDLENVPROC DXSetResourceShareHandleNV;
     PFNWGLDXOPENDEVICENVPROC             DXOpenDeviceNV;
     PFNWGLDXCLOSEDEVICENVPROC            DXCloseDeviceNV;
@@ -422,15 +424,37 @@ GLConvOpen(vlc_object_t *obj)
         return VLC_EGENERIC;
     }
 
-    if (interop->gl->ext != VLC_GL_EXT_WGL || !interop->gl->wgl.getExtensionsString)
+    if (interop->gl->surface == NULL)
         return VLC_EGENERIC;
 
-    const char *wglExt = interop->gl->wgl.getExtensionsString(interop->gl);
+    HDC hGLDC = NULL;
+    switch (interop->gl->surface->type)
+    {
+        case VOUT_WINDOW_TYPE_HWND:
+        case VOUT_WINDOW_TYPE_DUMMY:
+            hGLDC = wglGetCurrentDC();
+            break;
+        default: return VLC_EGENERIC;
+    }
+
+    if (hGLDC == NULL)
+        return VLC_EGENERIC;
+
+    struct wgl_vt vt;
+    vt.GetExtensionsStringEXT =
+        vlc_gl_GetProcAddress(interop->gl, "wglGetExtensionsStringEXT");
+    vt.GetExtensionsStringARB =
+        vlc_gl_GetProcAddress(interop->gl, "wglGetExtensionsStringARB");
+
+    const char *wglExt = NULL;
+    if (vt.GetExtensionsStringEXT)
+        wglExt = vt.GetExtensionsStringEXT();
+    else if (vt.GetExtensionsStringARB)
+        wglExt = vt.GetExtensionsStringARB(hGLDC);
 
     if (wglExt == NULL || !vlc_gl_StrHasToken(wglExt, "WGL_NV_DX_interop"))
         return VLC_EGENERIC;
 
-    struct wgl_vt vt;
 #define LOAD_EXT(name, type) do { \
     vt.name = (type) vlc_gl_GetProcAddress(interop->gl, "wgl" #name); \
     if (!vt.name) { \
-- 
2.30.1