[PATCH 5/7] win32u: Use a pbuffer to implement GL on memory DCs.

5 Jun 2025

From: Rémi Bernon rbernon@codeweavers.com
---
 dlls/opengl32/make_opengl    |   3 +
 dlls/opengl32/tests/opengl.c |  25 ++++----
 dlls/opengl32/unix_private.h |   3 +
 dlls/opengl32/unix_thunks.c  |   9 +--
 dlls/opengl32/unix_wgl.c     |  21 +++++++
 dlls/win32u/opengl.c         | 108 ++++++++++++++++++++++++++++++-----
 6 files changed, 137 insertions(+), 32 deletions(-)

diff --git a/dlls/opengl32/make_opengl b/dlls/opengl32/make_opengl
index bc8eb05aaa5..d43ee4abf3e 100755
--- a/dlls/opengl32/make_opengl
+++ b/dlls/opengl32/make_opengl
@@ -200,11 +200,14 @@ my %manual_unix_thunks =
      "glDebugMessageCallback" => 1,
      "glDebugMessageCallbackAMD" => 1,
      "glDebugMessageCallbackARB" => 1,
+     "glDrawPixels" => 1,
      "glFinish" => 1,
      "glFlush" => 1,
      "glGetIntegerv" => 1,
      "glGetString" => 1,
      "glGetStringi" => 1,
+     "glReadPixels" => 1,
+     "glViewport" => 1,
      "wglGetProcAddress" => 1,
      "wglSwapBuffers" => 1,
     );
diff --git a/dlls/opengl32/tests/opengl.c b/dlls/opengl32/tests/opengl.c
index 4443945c8c6..7828a51267d 100644
--- a/dlls/opengl32/tests/opengl.c
+++ b/dlls/opengl32/tests/opengl.c
@@ -1597,7 +1597,7 @@ static void test_bitmap_rendering( BOOL use_dib )
     ok( EqualRect( (RECT *)viewport, &expect_rect ), "got viewport %s\n", wine_dbgstr_rect( (RECT *)viewport ) );
glReadPixels( 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel );
-    todo_wine ok( (pixel & 0xffffff) == 0xcdcdcd, "got %#x\n", pixel );
+    ok( (pixel & 0xffffff) == 0xcdcdcd, "got %#x\n", pixel );
glClearColor( (float)0x22 / 0xff, (float)0x33 / 0xff, (float)0x44 / 0xff, (float)0x11 / 0xff );
     glClear( GL_COLOR_BUFFER_BIT );
@@ -1642,7 +1642,7 @@ static void test_bitmap_rendering( BOOL use_dib )
     ok( (pixel & 0xffffff) == 0x443322, "got %#x\n", pixel );
     if (pixels == buffer) read_bitmap_pixels( hdc, bmp, pixels, 4, 4, bpp );
     if (pixels2 == buffer2) read_bitmap_pixels( hdc, bmp2, pixels2, 12, 12, bpp );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
+    ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
     ok( (pixels2[0] & 0xffffff) == 0xdcdcdc, "got %#x\n", pixels2[0] );
@@ -1657,13 +1657,13 @@ static void test_bitmap_rendering( BOOL use_dib )
     /* pixels are read from the selected bitmap */
glReadPixels( 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel );
-    todo_wine ok( (pixel & 0xffffff) == 0xdcdcdc, "got %#x\n", pixel );
+    ok( (pixel & 0xffffff) == 0xdcdcdc, "got %#x\n", pixel );
if (use_dib)
     {
         memset( buffer2, 0xa5, sizeof(buffer2) );
         glReadPixels( 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel );
-        todo_wine ok( (pixel & 0xffffff) == 0xdcdcdc, "got %#x\n", pixel );
+        ok( (pixel & 0xffffff) == 0xdcdcdc, "got %#x\n", pixel );
         memset( buffer2, 0xdc, sizeof(buffer2) );
     }
@@ -1676,7 +1676,7 @@ static void test_bitmap_rendering( BOOL use_dib )
if (pixels == buffer) read_bitmap_pixels( hdc, bmp, pixels, 4, 4, bpp );
     if (pixels2 == buffer2) read_bitmap_pixels( hdc, bmp2, pixels2, 12, 12, bpp );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
+    ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
     ok( (pixels2[0] & 0xffffff) == 0xdcdcdc, "got %#x\n", pixels2[0] );
glFinish();
@@ -1685,8 +1685,8 @@ static void test_bitmap_rendering( BOOL use_dib )
     ok( (pixel & 0xffffff) == 0x223344, "got %#x\n", pixel );
     if (pixels == buffer) read_bitmap_pixels( hdc, bmp, pixels, 4, 4, bpp );
     if (pixels2 == buffer2) read_bitmap_pixels( hdc, bmp2, pixels2, 12, 12, bpp );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
-    todo_wine ok( (pixels2[0] & 0xffffff) == 0x443322, "got %#x\n", pixels2[0] );
+    ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
+    ok( (pixels2[0] & 0xffffff) == 0x443322, "got %#x\n", pixels2[0] );
ret = wglMakeCurrent( NULL, NULL );
@@ -1704,7 +1704,7 @@ static void test_bitmap_rendering( BOOL use_dib )
if (pixels == buffer) read_bitmap_pixels( hdc, bmp, pixels, 4, 4, bpp );
     if (pixels2 == buffer2) read_bitmap_pixels( hdc, bmp2, pixels2, 12, 12, bpp );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
+    ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
     ok( (pixels2[0] & 0xffffff) == 0x445566, "got %#x\n", pixels2[0] );
@@ -1726,7 +1726,7 @@ static void test_bitmap_rendering( BOOL use_dib )
if (pixels == buffer) read_bitmap_pixels( hdc, bmp, pixels, 4, 4, bpp );
     if (pixels2 == buffer2) read_bitmap_pixels( hdc, bmp2, pixels2, 12, 12, bpp );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
+    ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
     if (use_dib) todo_wine ok( (pixels2[0] & 0xffffff) == 0x03148, "got %#x\n", pixels2[0] );
     else ok( (pixels2[0] & 0xffffff) == 0x665544, "got %#x\n", pixels2[0] );
@@ -1743,7 +1743,7 @@ static void test_bitmap_rendering( BOOL use_dib )
if (pixels == buffer) read_bitmap_pixels( hdc, bmp, pixels, 4, 4, bpp );
     if (pixels2 == buffer2) read_bitmap_pixels( hdc, bmp2, pixels2, 12, 12, bpp );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
+    ok( (pixels[0] & 0xffffff) == 0x223344, "got %#x\n", pixels[0] );
     ok( (pixels2[0] & 0xffffff) == 0x667788, "got %#x\n", pixels2[0] );
@@ -1789,6 +1789,7 @@ static void test_d3dkmt_rendering(void)
     NTSTATUS status;
     HGLRC hglrc;
+    memset( (void *)pixels, 0xcd, sizeof(*pixels) * 4 * 4 );
     create.pMemory = pixels;
     create.Format = D3DDDIFMT_A8R8G8B8;
     create.Width = 4;
@@ -1858,7 +1859,7 @@ static void test_d3dkmt_rendering(void)
memset( (void *)pixels, 0xcd, sizeof(*pixels) * 4 * 4 );
     glReadPixels( 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel );
-    todo_wine ok( (pixel & 0xffffff) == 0xcdcdcd, "got %#x\n", pixel );
+    ok( (pixel & 0xffffff) == 0xcdcdcd, "got %#x\n", pixel );
glClearColor( (float)0x44 / 0xff, (float)0x33 / 0xff, (float)0x22 / 0xff, (float)0x11 / 0xff );
     glClear( GL_COLOR_BUFFER_BIT );
@@ -1881,7 +1882,7 @@ static void test_d3dkmt_rendering(void)
     ok( (pixels[0] & 0xffffff) == 0x556677, "got %#x\n", pixels[0] );
     glReadPixels( 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel );
     ok( (pixel & 0xffffff) == 0x223344, "got %#x\n", pixel );
-    todo_wine ok( (pixels[0] & 0xffffff) == 0x443322, "got %#x\n", pixels[0] );
+    ok( (pixels[0] & 0xffffff) == 0x443322, "got %#x\n", pixels[0] );
glReadPixels( 0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &pixel );
     ok( (pixel & 0xffffff) == 0x223344, "got %#x\n", pixel );
diff --git a/dlls/opengl32/unix_private.h b/dlls/opengl32/unix_private.h
index 30b90545105..c15bda2c99a 100644
--- a/dlls/opengl32/unix_private.h
+++ b/dlls/opengl32/unix_private.h
@@ -82,6 +82,9 @@ extern PROC wrap_wglGetProcAddress( TEB *teb, LPCSTR lpszProc );
 extern BOOL wrap_wglMakeCurrent( TEB *teb, HDC hDc, HGLRC newContext );
 extern void wrap_glFinish( TEB *teb );
 extern void wrap_glFlush( TEB *teb );
+extern void wrap_glDrawPixels( TEB *teb, GLsizei width, GLsizei height, GLenum format, GLenum type, const void *pixels );
+extern void wrap_glReadPixels( TEB *teb, GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, void *pixels );
+extern void wrap_glViewport( TEB *teb, GLint x, GLint y, GLsizei width, GLsizei height );
 extern BOOL wrap_wglSwapBuffers( TEB *teb, HDC hdc );
 extern BOOL wrap_wglShareLists( TEB *teb, HGLRC hrcSrvShare, HGLRC hrcSrvSource );
 extern void wrap_glGetIntegerv( TEB *teb, GLenum pname, GLint *data );
diff --git a/dlls/opengl32/unix_thunks.c b/dlls/opengl32/unix_thunks.c
index ae97dfbec47..91aaadbe9c0 100644
--- a/dlls/opengl32/unix_thunks.c
+++ b/dlls/opengl32/unix_thunks.c
@@ -718,8 +718,7 @@ static NTSTATUS gl_glDrawElements( void *args )
 static NTSTATUS gl_glDrawPixels( void *args )
 {
     struct glDrawPixels_params *params = args;
-    const struct opengl_funcs *funcs = params->teb->glTable;
-    funcs->p_glDrawPixels( params->width, params->height, params->format, params->type, params->pixels );
+    wrap_glDrawPixels( params->teb, params->width, params->height, params->format, params->type, params->pixels );
     set_context_attribute( params->teb, -1 /* unsupported */, NULL, 0 );
     return STATUS_SUCCESS;
 }
@@ -2203,8 +2202,7 @@ static NTSTATUS gl_glReadBuffer( void *args )
 static NTSTATUS gl_glReadPixels( void *args )
 {
     struct glReadPixels_params *params = args;
-    const struct opengl_funcs *funcs = params->teb->glTable;
-    funcs->p_glReadPixels( params->x, params->y, params->width, params->height, params->format, params->type, params->pixels );
+    wrap_glReadPixels( params->teb, params->x, params->y, params->width, params->height, params->format, params->type, params->pixels );
     set_context_attribute( params->teb, -1 /* unsupported */, NULL, 0 );
     return STATUS_SUCCESS;
 }
@@ -3085,8 +3083,7 @@ static NTSTATUS gl_glVertexPointer( void *args )
 static NTSTATUS gl_glViewport( void *args )
 {
     struct glViewport_params *params = args;
-    const struct opengl_funcs *funcs = params->teb->glTable;
-    funcs->p_glViewport( params->x, params->y, params->width, params->height );
+    wrap_glViewport( params->teb, params->x, params->y, params->width, params->height );
     set_context_attribute( params->teb, GL_VIEWPORT, &params->x, 2 * sizeof(GLint) + 2 * sizeof(GLsizei) );
     return STATUS_SUCCESS;
 }
diff --git a/dlls/opengl32/unix_wgl.c b/dlls/opengl32/unix_wgl.c
index f009c74e209..d203f4781a7 100644
--- a/dlls/opengl32/unix_wgl.c
+++ b/dlls/opengl32/unix_wgl.c
@@ -1010,6 +1010,27 @@ void wrap_glFlush( TEB *teb )
     flush_context( teb, funcs->p_glFlush );
 }
+void wrap_glDrawPixels( TEB *teb, GLsizei width, GLsizei height, GLenum format, GLenum type, const void *pixels )
+{
+    const struct opengl_funcs *funcs = teb->glTable;
+    flush_context( teb, NULL );
+    funcs->p_glDrawPixels( width, height, format, type, pixels );
+}
+
+void wrap_glReadPixels( TEB *teb, GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, void *pixels )
+{
+    const struct opengl_funcs *funcs = teb->glTable;
+    flush_context( teb, NULL );
+    funcs->p_glReadPixels( x, y, width, height, format, type, pixels );
+}
+
+void wrap_glViewport( TEB *teb, GLint x, GLint y, GLsizei width, GLsizei height )
+{
+    const struct opengl_funcs *funcs = teb->glTable;
+    flush_context( teb, NULL );
+    funcs->p_glViewport( x, y, width, height );
+}
+
 BOOL wrap_wglSwapBuffers( TEB *teb, HDC hdc )
 {
     const struct opengl_funcs *funcs = get_dc_funcs( hdc );
diff --git a/dlls/win32u/opengl.c b/dlls/win32u/opengl.c
index 13c9d230925..310beaa8922 100644
--- a/dlls/win32u/opengl.c
+++ b/dlls/win32u/opengl.c
@@ -45,6 +45,9 @@ struct wgl_context
     const struct opengl_funcs *funcs;
     void *driver_private;
     int pixel_format;
+
+    HBITMAP memory_bitmap;
+    struct wgl_pbuffer *memory_pbuffer;
 };
struct wgl_pbuffer
@@ -935,6 +938,76 @@ static int win32u_wglGetPixelFormat( HDC hdc )
     return format > 0 ? format : 0;
 }
+static struct wgl_pbuffer *create_memory_pbuffer( HDC hdc, int format )
+{
+    const struct opengl_funcs *funcs = &display_funcs;
+    struct wgl_pbuffer *pbuffer = NULL;
+    BITMAPOBJ *bmp;
+    dib_info dib;
+    BOOL ret;
+    DC *dc;
+
+    if (!(dc = get_dc_ptr( hdc ))) return NULL;
+    if (get_gdi_object_type( hdc ) != NTGDI_OBJ_MEMDC) ret = FALSE;
+    else if (!(bmp = GDI_GetObjPtr( dc->hBitmap, NTGDI_OBJ_BITMAP ))) ret = FALSE;
+    else
+    {
+        ret = init_dib_info_from_bitmapobj( &dib, bmp );
+        GDI_ReleaseObj( dc->hBitmap );
+    }
+    release_dc_ptr( dc );
+
+    if (ret)
+    {
+        int width = dib.rect.right - dib.rect.left, height = dib.rect.bottom - dib.rect.top;
+        pbuffer = funcs->p_wglCreatePbufferARB( hdc, format, width, height, NULL );
+    }
+
+    if (pbuffer) TRACE( "Created pbuffer %p for memory DC %p\n", pbuffer, hdc );
+    else WARN( "Failed to create pbuffer for memory DC %p\n", hdc );
+    return pbuffer;
+}
+
+static BOOL flush_memory_pbuffer( struct wgl_context *context, HDC hdc, BOOL write, void (*flush)(void) )
+{
+    const struct opengl_funcs *funcs = &display_funcs;
+    BITMAPOBJ *bmp;
+    DC *dc;
+
+    if (flush) flush();
+
+    if (!(dc = get_dc_ptr( hdc ))) return TRUE;
+    if ((bmp = GDI_GetObjPtr( dc->hBitmap, NTGDI_OBJ_BITMAP )))
+    {
+        char buffer[FIELD_OFFSET( BITMAPINFO, bmiColors[256] )];
+        BITMAPINFO *info = (BITMAPINFO *)buffer;
+        struct bitblt_coords src = {0};
+        struct gdi_image_bits bits;
+
+        if (dc->hBitmap != context->memory_bitmap) write = TRUE;
+        context->memory_bitmap = dc->hBitmap;
+
+        if (!get_image_from_bitmap( bmp, info, &bits, &src ))
+        {
+            int width = info->bmiHeader.biWidth, height = abs( info->bmiHeader.biHeight );
+            if (write) funcs->p_glDrawPixels( width, height, GL_BGRA, GL_UNSIGNED_BYTE, bits.ptr );
+            else funcs->p_glReadPixels( 0, 0, width, height, GL_BGRA, GL_UNSIGNED_BYTE, bits.ptr );
+        }
+        GDI_ReleaseObj( dc->hBitmap );
+    }
+    release_dc_ptr( dc );
+
+    return TRUE;
+}
+
+static void destroy_memory_pbuffer( struct wgl_context *context, HDC hdc )
+{
+    const struct opengl_funcs *funcs = context->funcs;
+    flush_memory_pbuffer( context, hdc, FALSE, funcs->p_glFinish );
+    funcs->p_wglDestroyPbufferARB( context->memory_pbuffer );
+    context->memory_pbuffer = NULL;
+}
+
 static BOOL set_dc_pixel_format( HDC hdc, int new_format, BOOL internal )
 {
     const struct opengl_funcs *funcs;
@@ -1038,7 +1111,7 @@ static struct wgl_context *context_create( HDC hdc, struct wgl_context *shared,
     context->funcs = funcs;
     context->pixel_format = format;
-    if (!driver_funcs->p_context_create( hdc, format, shared_private, attribs, &context->driver_private ))
+    if (!context->driver_funcs->p_context_create( hdc, format, shared_private, attribs, &context->driver_private ))
     {
         free( context );
         return NULL;
@@ -1079,14 +1152,18 @@ static BOOL win32u_wglDeleteContext( struct wgl_context *context )
static BOOL win32u_wglMakeContextCurrentARB( HDC draw_hdc, HDC read_hdc, struct wgl_context *context )
 {
+    HDC hdc = draw_hdc, prev_draw = NtCurrentTeb()->glReserved1[0];
+    struct wgl_context *prev_context = NtCurrentTeb()->glContext;
     const struct opengl_driver_funcs *funcs;
     int format;
TRACE( "draw_hdc %p, read_hdc %p, context %p\n", draw_hdc, read_hdc, context );
+    if (prev_context && prev_context->memory_pbuffer) destroy_memory_pbuffer( prev_context, prev_draw );
+
     if (!context)
     {
-        if (!(context = NtCurrentTeb()->glContext)) return TRUE;
+        if (!(context = prev_context)) return TRUE;
         funcs = context->driver_funcs;
         if (!funcs->p_context_make_current( NULL, NULL, NULL )) return FALSE;
         NtCurrentTeb()->glContext = NULL;
@@ -1106,9 +1183,16 @@ static BOOL win32u_wglMakeContextCurrentARB( HDC draw_hdc, HDC read_hdc, struct
         return FALSE;
     }
+    if ((context->memory_pbuffer = create_memory_pbuffer( draw_hdc, context->pixel_format )))
+    {
+        if (read_hdc != draw_hdc) ERR( "read != draw not supported\n" );
+        draw_hdc = read_hdc = context->memory_pbuffer->hdc;
+    }
+
     funcs = context->driver_funcs;
     if (!funcs->p_context_make_current( draw_hdc, read_hdc, context->driver_private )) return FALSE;
     NtCurrentTeb()->glContext = context;
+    if (context->memory_pbuffer) flush_memory_pbuffer( context, hdc, TRUE, NULL );
     return TRUE;
 }
@@ -1147,7 +1231,7 @@ static struct wgl_pbuffer *win32u_wglCreatePbufferARB( HDC hdc, int format, int
         return NULL;
     }
     NtGdiSetPixelFormat( pbuffer->hdc, format );
-    pbuffer->driver_funcs = funcs == &display_funcs ? display_driver_funcs : memory_driver_funcs;
+    pbuffer->driver_funcs = display_driver_funcs;
     pbuffer->funcs = funcs;
     pbuffer->width = width;
     pbuffer->height = height;
@@ -1553,13 +1637,14 @@ static BOOL win32u_wgl_context_flush( struct wgl_context *context, void (*flush)
     else interval = get_window_swap_interval( hwnd );
TRACE( "context %p, hwnd %p, draw_hdc %p, interval %d, flush %p\n", context, hwnd, draw_hdc, interval, flush );
+
+    if (context->memory_pbuffer) return flush_memory_pbuffer( context, draw_hdc, FALSE, flush );
     return context->driver_funcs->p_context_flush( context->driver_private, hwnd, draw_hdc, interval, flush );
 }
static BOOL win32u_wglSwapBuffers( HDC hdc )
 {
     struct wgl_context *context = NtCurrentTeb()->glContext;
-    const struct opengl_driver_funcs *driver_funcs;
     const struct opengl_funcs *funcs;
     int interval;
     HWND hwnd;
@@ -1569,12 +1654,13 @@ static BOOL win32u_wglSwapBuffers( HDC hdc )
         RtlSetLastWin32Error( ERROR_DC_NOT_FOUND );
         return FALSE;
     }
-    driver_funcs = funcs == &display_funcs ? display_driver_funcs : memory_driver_funcs;
+    context->driver_funcs = funcs == &display_funcs ? display_driver_funcs : memory_driver_funcs;
if (!(hwnd = NtUserWindowFromDC( hdc ))) interval = 0;
     else interval = get_window_swap_interval( hwnd );
-    return driver_funcs->p_swap_buffers( context ? context->driver_private : NULL, hwnd, hdc, interval );
+    if (context->memory_pbuffer) return flush_memory_pbuffer( context, hdc, FALSE, funcs->p_glFlush );
+    return context->driver_funcs->p_swap_buffers( context ? context->driver_private : NULL, hwnd, hdc, interval );
 }
static BOOL win32u_wglSwapIntervalEXT( int interval )
@@ -1635,7 +1721,7 @@ static void init_opengl_funcs( struct opengl_funcs *funcs, const struct opengl_d
 #undef USE_GL_FUNC
 }
-static void memory_funcs_init(void)
+static inline void memory_funcs_init(void)
 {
     if (!osmesa_get_wgl_driver( &memory_driver_funcs )) WARN( "Failed to initialize OSMesa functions\n" );
@@ -1749,18 +1835,12 @@ static const struct opengl_funcs *get_dc_funcs( HDC hdc, const struct opengl_fun
     release_dc_ptr( dc );
if (is_disabled) return NULL;
-    if (is_display)
+    if (is_display || is_memdc)
     {
         static pthread_once_t display_init_once = PTHREAD_ONCE_INIT;
         pthread_once( &display_init_once, display_funcs_init );
         return &display_funcs;
     }
-    if (is_memdc)
-    {
-        static pthread_once_t memory_init_once = PTHREAD_ONCE_INIT;
-        pthread_once( &memory_init_once, memory_funcs_init );
-        return &memory_funcs;
-    }
     return NULL;
 }
-- 
GitLab


https://gitlab.winehq.org/wine/wine/-/merge_requests/8210

    

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[PATCH 5/7] win32u: Use a pbuffer to implement GL on memory DCs.