st/wgl: Add a few more comments.

2 files changed, 38 insertions, 6 deletions

diff --git a/src/gallium/state_trackers/wgl/stw_icd.h b/src/gallium/state_trackers/wgl/stw_icd.h
index 02eb543fef0..9f386c9c104 100644
--- a/src/gallium/state_trackers/wgl/stw_icd.h
+++ b/src/gallium/state_trackers/wgl/stw_icd.h
@@ -25,6 +25,13 @@
  *
  **************************************************************************/
 
+/**
+ * @file
+ *
+ * This header defines the interface used by the system's opengl32.dll and the
+ * Installable Client Driver (ICD).
+ */
+
 #ifndef STW_ICD_H
 #define STW_ICD_H
 
@@ -447,14 +454,26 @@ typedef struct _GLCBPRESENTBUFFERSDATA
  */
 typedef struct _GLCALLBACKTABLE
 {
-   /** Unused */
-   PROC wglCbSetCurrentValue;
+   /**
+    * Set per-thread driver private data.
+    *
+    * Unused.
+    **/
+   void (APIENTRY *wglCbSetCurrentValue)(void *pvData);
 
-   /** Unused */
-   PROC wglCbGetCurrentValue;
+   /**
+    * Get per-thread private data.
+    *
+    * Unused.
+    */
+   void * (APIENTRY *wglCbGetCurrentValue)(void);
 
-   /** Unused */
-   PROC wglCbGetDhglrc;
+   /**
+    * Get the ICD GHGLRC handle corresponding to the specified hglrc handle.
+    *
+    * Currently unused.
+    */
+   DHGLRC (APIENTRY *wglCbGetDhglrc)(HGLRC hglrc);
 
    /** Unused */
    PROC wglCbGetDdHandle;
diff --git a/src/gallium/state_trackers/wgl/stw_wgl.c b/src/gallium/state_trackers/wgl/stw_wgl.c
index d38bfbefdd7..17b6da8528b 100644
--- a/src/gallium/state_trackers/wgl/stw_wgl.c
+++ b/src/gallium/state_trackers/wgl/stw_wgl.c
@@ -25,6 +25,19 @@
  *
  **************************************************************************/
 
+/**
+ * @file
+ *
+ * Fake WGL API implementation.
+ *
+ * These functions implement the WGL API, on top of the ICD DDI, so that the
+ * resulting DLL can be used as a drop-in replacement for the system's
+ * opengl32.dll.
+ *
+ * These functions never get called for ICD drivers, which use exclusively the
+ * ICD DDI, i.e., the Drv* entrypoints.
+ */
+
 #include <windows.h>
 
 #include "util/u_debug.h"