[PATCH 0/1] MR6513: opengl32: Add WGL_DOUBLE_BUFFER_ARB to the explicit sort list.

[Aida Jonikienė (＠DodoGTA)]

The Legend of Pirates Online expects the formats without WGL_DOUBLE_BUFFER_ARB
to be listed first in wglChoosePixelFormatARB() (otherwise it goes into a special
wglBindTexImageARB() path which causes blank rendering on both winex11 and winewayland)
which was the old winex11 behavior that this change now matches.

Fixes: 272c55ac257 ("opengl32: Add default implementation for wglChoosePixelFormatARB.")

[PATCH 1/1] opengl32: Add WGL_DOUBLE_BUFFER_ARB to the explicit sort list.

[Aida Jonikienė]

From: Aida Jonikienė

The Legend of Pirates Online expects the formats without WGL_DOUBLE_BUFFER_ARB
to be listed first in wglChoosePixelFormatARB() (otherwise it goes into a special
wglBindTexImageARB() path which causes blank rendering on both winex11 and winewayland)
which was the old winex11 behavior that this change now matches.

Fixes: 272c55ac257 ("opengl32: Add default implementation for wglChoosePixelFormatARB.")
---
 dlls/opengl32/wgl.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/dlls/opengl32/wgl.c b/dlls/opengl32/wgl.c
index c6414054ff5..5b176291e70 100644
--- a/dlls/opengl32/wgl.c
+++ b/dlls/opengl32/wgl.c
@@ -754,6 +754,7 @@ BOOL WINAPI wglChoosePixelFormatARB( HDC hdc, const int *attribs_int, const FLOA
                              ctx.attribs[2 * i + 1] );

/* Some attributes we always want to sort by (values don't matter for sorting) */
+    compare_formats_ctx_set_attrib( &ctx, WGL_DOUBLE_BUFFER_ARB, 0 );
     compare_formats_ctx_set_attrib( &ctx, WGL_ACCELERATION_ARB, 0 );
     compare_formats_ctx_set_attrib( &ctx, WGL_COLOR_BITS_ARB, 0 );
     compare_formats_ctx_set_attrib( &ctx, WGL_ACCUM_BITS_ARB, 0 );

[Rémi Bernon (＠rbernon)]

This isn't what native AMD drivers seem to be doing, see https://testbot.winehq.org/JobDetails.pl?Key=148500&f101=exe64.report&am.... It would be interesting to write tests doing exactly the same wglChoosePixelFormatARB query as the game and see what is supposed to be returned.

[Aida Jonikienė (＠DodoGTA)]

On Thu Sep 19 13:11:52 2024 +0000, Rémi Bernon wrote:
> This isn't what native AMD drivers seem to be doing, see
> https://testbot.winehq.org/JobDetails.pl?Key=148500&f101=exe64.report&am....
> It would be interesting to write tests doing exactly the same
> wglChoosePixelFormatARB query as the game and see what is supposed to be returned.

The game calls `wglChoosePixelFormatARB()` with a non-NULL HDC, an integer attribute list of `{WGL_SUPPORT_OPENGL_ARB, TRUE, WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB, 0}`, an empty float attribute list and max format count of 1024 according to apitrace

I'll try to add tests for this a bit later

[Aida Jonikienė (＠DodoGTA)]

On Thu Sep 19 14:54:22 2024 +0000, Aida Jonikienė wrote:
> The game initially calls `wglChoosePixelFormatARB()` with a non-NULL
> HDC, an integer attribute list of `{WGL_SUPPORT_OPENGL_ARB, TRUE,
> WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB, 0}`, an empty float attribute
> list and max format count of 1024 according to apitrace (in later calls
> it uses integer attributes of `{WGL_SUPPORT_OPENGL_ARB, TRUE,
> WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB, WGL_DRAW_TO_PBUFFER_ARB, TRUE,
> WGL_BIND_TO_TEXTURE_RGB_ARB, TRUE, 0}`)
> I see the game is picking a double-buffered pixel format without my MR
> and a non-double-buffered one with it applied too
> I'll try to add tests for this a bit later

I realized some time ago that this game is using `wglBind/ReleaseTexImageARB()` in the double-buffered pixel format path (which seem to be semi-broken functions on both winex11 and winewayland)

I guess I should turn this MR into a potential fix for those function implementations then (which is more likely to be merged than this workaround)