2017-01-18 1:31 GMT+08:00 Brian Paul <bri...@vmware.com>: > On 01/17/2017 06:44 AM, Boyan Ding wrote: >> >> st will only add back buffer attachment to window framebuffer when >> visual is in double-buffer mode. However, some applications may >> render to front buffer even if they have chosen a double-buffer visual. >> In this case, no color buffer will be attached when rendering. i965 >> handles this case correctly, in which it adds both front and back buffer >> attachments. Do the same thing in st. >> >> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99116 >> Signed-off-by: Boyan Ding <boyan.j.d...@gmail.com> >> --- >> src/mesa/state_tracker/st_manager.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/src/mesa/state_tracker/st_manager.c >> b/src/mesa/state_tracker/st_manager.c >> index c3d8286b5a..aa53edfecb 100644 >> --- a/src/mesa/state_tracker/st_manager.c >> +++ b/src/mesa/state_tracker/st_manager.c >> @@ -417,7 +417,6 @@ st_framebuffer_create(struct st_context *st, >> { >> struct st_framebuffer *stfb; >> struct gl_config mode; >> - gl_buffer_index idx; >> >> if (!stfbi) >> return NULL; >> @@ -466,11 +465,12 @@ st_framebuffer_create(struct st_context *st, >> stfb->iface_stamp = p_atomic_read(&stfbi->stamp) - 1; >> >> /* add the color buffer */ >> - idx = stfb->Base._ColorDrawBufferIndexes[0]; >> - if (!st_framebuffer_add_renderbuffer(stfb, idx)) { >> + if (!st_framebuffer_add_renderbuffer(stfb, BUFFER_FRONT_LEFT)) { >> free(stfb); >> return NULL; >> } >> + if (mode.doubleBufferMode) >> + st_framebuffer_add_renderbuffer(stfb, BUFFER_BACK_LEFT); >> >> st_framebuffer_add_renderbuffer(stfb, BUFFER_DEPTH); >> st_framebuffer_add_renderbuffer(stfb, BUFFER_ACCUM); >> > > > I believe we have code in the state tracker to allocate the front buffer on > demand when the app actually tries to draw to it. Can you look into that? > > -Brian >
Hi, I don't think I find that. The only place in state tracker where _mesa_add_renderbuffer is called is st_framebuffer_create and only one of the front and back buffers is allocated based on the default behavior. When update_framebuffer_state() in state tracker is called after draw buffer changes to front, state tracker will find it refers to a null renderbuffer and remove it afterwards. So the reasonable way is to allocate the front buffer in update_framebuffer_state when front buffer is the draw buffer but not allocated? Regards, Boyan Ding _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
