[Mesa-dev] [PATCH 5/5] st/egl: add premultiplied alpha support to wayland

[Chia-I Wu]

On Thu, Sep 8, 2011 at 3:13 PM, Benjamin Franzke
<benjaminfranzke at googlemail.com> wrote:
> 2011/9/8 Chia-I Wu <olvaffe at gmail.com>:
>> From: Chia-I Wu <olv at lunarg.com>
>>
>> Return true for NATIVE_PARAM_PREMULTIPLIED_ALPHA when all formats with
>> alpha support premultiplied alpha.  Currently, it means when argb32 and
>> argb32_pre are both supported.
>> ---
>>  .../state_trackers/egl/wayland/native_drm.c        |    8 ++++++--
>>  .../state_trackers/egl/wayland/native_shm.c        |    6 +++++-
>>  .../state_trackers/egl/wayland/native_wayland.c    |   18 ++++++++++++++++++
>>  .../state_trackers/egl/wayland/native_wayland.h    |    3 +++
>>  4 files changed, 32 insertions(+), 3 deletions(-)
>>
>> diff --git a/src/gallium/state_trackers/egl/wayland/native_drm.c b/src/gallium/state_trackers/egl/wayland/native_drm.c
>> index facab32..e177e7c 100644
>> --- a/src/gallium/state_trackers/egl/wayland/native_drm.c
>> +++ b/src/gallium/state_trackers/egl/wayland/native_drm.c
>> @@ -114,8 +114,8 @@ wayland_create_drm_buffer(struct wayland_display *display,
>>
>>    switch (surface->color_format) {
>>    case PIPE_FORMAT_B8G8R8A8_UNORM:
>> -      /* assume premultiplied */
>> -      format = WL_DRM_FORMAT_PREMULTIPLIED_ARGB32;
>> +      format = (surface->premultiplied_alpha) ?
>> +         WL_DRM_FORMAT_PREMULTIPLIED_ARGB32 : WL_DRM_FORMAT_ARGB32;
>>       break;
>>    case PIPE_FORMAT_B8G8R8X8_UNORM:
>>       format = WL_DRM_FORMAT_XRGB32;
>> @@ -255,6 +255,10 @@ wayland_drm_display_init_screen(struct native_display *ndpy)
>>    if (!wayland_drm_display_add_configs(drmdpy))
>>       return FALSE;
>>
>> +   /* check that premultiplied alpha is supported for all formats with alpha */
>> +   if (!drmdpy->argb32 || drmdpy->argb32_pre)
>> +      drmdpy->base.param_premultiplied_alpha = TRUE;
>
> Why enable premultiplied alpha if argb32 is not exposed?
> What isnt covered with just: "if (drmdpy->argb32_pre)"?.
Yes, it is simpler.  What I intended to do is to enable pre-multiplied
alpha when all formats that have alpha also support pre-multiplied
alpha.  In the case there is no format that has alpha
(!drmdpy->argb32), pre-multiplied alpha can be enabled.

>> +
>>    drmdpy->base.base.screen =
>>       drmdpy->event_handler->new_drm_screen(&drmdpy->base.base,
>>                                             NULL, drmdpy->fd);
>> diff --git a/src/gallium/state_trackers/egl/wayland/native_shm.c b/src/gallium/state_trackers/egl/wayland/native_shm.c
>> index 5882e74..e2d2437 100644
>> --- a/src/gallium/state_trackers/egl/wayland/native_shm.c
>> +++ b/src/gallium/state_trackers/egl/wayland/native_shm.c
>> @@ -95,7 +95,8 @@ wayland_create_shm_buffer(struct wayland_display *display,
>>
>>    switch (surface->color_format) {
>>    case PIPE_FORMAT_B8G8R8A8_UNORM:
>> -      format = WL_SHM_FORMAT_PREMULTIPLIED_ARGB32;
>> +      format = (surface->premultiplied_alpha) ?
>> +         WL_SHM_FORMAT_PREMULTIPLIED_ARGB32 : WL_SHM_FORMAT_ARGB32;
>>       break;
>>    case PIPE_FORMAT_B8G8R8X8_UNORM:
>>       format = WL_SHM_FORMAT_XRGB32;
>> @@ -165,6 +166,9 @@ wayland_shm_display_init_screen(struct native_display *ndpy)
>>    if (!wayland_shm_display_add_configs(shmdpy))
>>       return FALSE;
>>
>> +   /* assume all formats are supported */
>> +   shmdpy->base.param_premultiplied_alpha = TRUE;
>> +
>>    winsys = wayland_create_sw_winsys(shmdpy->base.dpy);
>>    if (!winsys)
>>       return FALSE;
>> diff --git a/src/gallium/state_trackers/egl/wayland/native_wayland.c b/src/gallium/state_trackers/egl/wayland/native_wayland.c
>> index 14cc908..b2dab8f 100644
>> --- a/src/gallium/state_trackers/egl/wayland/native_wayland.c
>> +++ b/src/gallium/state_trackers/egl/wayland/native_wayland.c
>> @@ -60,9 +60,13 @@ static int
>>  wayland_display_get_param(struct native_display *ndpy,
>>                           enum native_param_type param)
>>  {
>> +   struct wayland_display *display = wayland_display(ndpy);
>>    int val;
>>
>>    switch (param) {
>> +   case NATIVE_PARAM_PREMULTIPLIED_ALPHA:
>> +      val = display->param_premultiplied_alpha;
>> +      break;
>>    case NATIVE_PARAM_USE_NATIVE_BUFFER:
>>    case NATIVE_PARAM_PRESERVE_BUFFER:
>>    case NATIVE_PARAM_MAX_SWAP_INTERVAL:
>> @@ -283,6 +287,20 @@ wayland_surface_present(struct native_surface *nsurf,
>>    if (ctrl->preserve || ctrl->swap_interval)
>>       return FALSE;
>>
>> +   /* force buffers to be re-created if they will be presented differently */
>> +   if (surface->premultiplied_alpha != ctrl->premultiplied_alpha) {
>> +      enum wayland_buffer_type buffer;
>> +
>> +      for (buffer = 0; buffer < WL_BUFFER_COUNT; ++buffer) {
>> +         if (surface->buffer[buffer]) {
>> +            wl_buffer_destroy(surface->buffer[buffer]);
>> +            surface->buffer[buffer] = NULL;
>> +         }
>> +      }
>> +
>> +      surface->premultiplied_alpha = ctrl->premultiplied_alpha;
>> +   }
>> +
>>    switch (ctrl->natt) {
>>    case NATIVE_ATTACHMENT_FRONT_LEFT:
>>       ret = TRUE;
>> diff --git a/src/gallium/state_trackers/egl/wayland/native_wayland.h b/src/gallium/state_trackers/egl/wayland/native_wayland.h
>> index 93e670b..6cf98a8 100644
>> --- a/src/gallium/state_trackers/egl/wayland/native_wayland.h
>> +++ b/src/gallium/state_trackers/egl/wayland/native_wayland.h
>> @@ -44,6 +44,8 @@ struct wayland_display {
>>
>>    struct wayland_config *configs;
>>    int num_configs;
>> +   /* true if all formats with alpha support premultiplied alpha */
>> +   boolean param_premultiplied_alpha;
>>
>>    struct wl_buffer *(*create_buffer)(struct wayland_display *display,
>>                                       struct wayland_surface *surface,
>> @@ -79,6 +81,7 @@ struct wayland_surface {
>>    unsigned int attachment_mask;
>>
>>    boolean block_swap_buffers;
>> +   boolean premultiplied_alpha;
>>  };
>>
>>  struct wayland_config {
>> --
>> 1.7.5.4
>>
>>
>



-- 
olv at LunarG.com