[Mesa-dev] [PATCH v3] gallium/hud: control visibility at startup and runtime.

[Jimmy Berry]

On Mon, Nov 9, 2015 at 11:28 AM, Brian Paul <brianp at vmware.com> wrote:
> On 11/07/2015 09:05 PM, Jimmy Berry wrote:
>>
>> - env GALLIUM_HUD_VISIBLE: control default visibility
>> - env GALLIUM_HUD_SIGNAL_TOGGLE: toggle visibility via signal
>> ---
>>   docs/envvars.html                       |  6 ++++++
>>   src/gallium/auxiliary/hud/hud_context.c | 28
>> ++++++++++++++++++++++++++++
>>   2 files changed, 34 insertions(+)
>>
>> diff --git a/docs/envvars.html b/docs/envvars.html
>> index bdfe999..530bbb7 100644
>> --- a/docs/envvars.html
>> +++ b/docs/envvars.html
>> @@ -179,6 +179,12 @@ Mesa EGL supports different sets of environment
>> variables.  See the
>>   <li>GALLIUM_HUD - draws various information on the screen, like
>> framerate,
>>       cpu load, driver statistics, performance counters, etc.
>>       Set GALLIUM_HUD=help and run e.g. glxgears for more info.
>> +<li>GALLIUM_HUD_VISIBLE - control default visibility, defaults to true.
>> +<li>GALLIUM_HUD_TOGGLE_SIGNAL - toggle visibility via user specified
>> signal.
>> +    Especially useful to toggle hud at specific points of application and
>> +    disable for unencumbered viewing the rest of the time. For example,
>> set
>> +    GALLIUM_HUD_VISIBLE to false and GALLIUM_HUD_SIGNAL_TOGGLE to 10
>> (SIGUSR1).
>> +    Use kill -10 <pid> to toggle the hud as desired.
>>   <li>GALLIUM_LOG_FILE - specifies a file for logging all errors,
>> warnings, etc.
>>       rather than stderr.
>>   <li>GALLIUM_PRINT_OPTIONS - if non-zero, print all the Gallium
>> environment
>> diff --git a/src/gallium/auxiliary/hud/hud_context.c
>> b/src/gallium/auxiliary/hud/hud_context.c
>> index ffe30b8..31e55cd 100644
>> --- a/src/gallium/auxiliary/hud/hud_context.c
>> +++ b/src/gallium/auxiliary/hud/hud_context.c
>> @@ -33,6 +33,7 @@
>>    * Set GALLIUM_HUD=help for more info.
>>    */
>>
>> +#include <signal.h>
>>   #include <stdio.h>
>>
>>   #include "hud/hud_context.h"
>> @@ -51,6 +52,8 @@
>>   #include "tgsi/tgsi_text.h"
>>   #include "tgsi/tgsi_dump.h"
>>
>> +/* Control the visibility of all HUD contexts */
>> +static boolean huds_visible = TRUE;
>>
>>   struct hud_context {
>>      struct pipe_context *pipe;
>> @@ -95,6 +98,11 @@ struct hud_context {
>>      } text, bg, whitelines;
>>   };
>>
>> +static void
>> +signal_visible_handler(int sig, siginfo_t *siginfo, void *context)
>> +{
>> +   huds_visible = !huds_visible;
>> +}
>>
>>   static void
>>   hud_draw_colored_prims(struct hud_context *hud, unsigned prim,
>> @@ -441,6 +449,9 @@ hud_draw(struct hud_context *hud, struct pipe_resource
>> *tex)
>>      struct hud_pane *pane;
>>      struct hud_graph *gr;
>>
>> +   if (!huds_visible)
>> +      return;
>> +
>>      hud->fb_width = tex->width0;
>>      hud->fb_height = tex->height0;
>>      hud->constants.two_div_fb_width = 2.0f / hud->fb_width;
>> @@ -1125,6 +1136,10 @@ hud_create(struct pipe_context *pipe, struct
>> cso_context *cso)
>>      struct pipe_sampler_view view_templ;
>>      unsigned i;
>>      const char *env = debug_get_option("GALLIUM_HUD", NULL);
>> +   long signo = debug_get_num_option("GALLIUM_HUD_TOGGLE_SIGNAL", 0);
>> +   boolean sig_handled = FALSE;
>> +   struct sigaction action = {};
>> +   huds_visible = debug_get_bool_option("GALLIUM_HUD_VISIBLE", TRUE);
>>
>>      if (!env || !*env)
>>         return NULL;
>> @@ -1267,6 +1282,19 @@ hud_create(struct pipe_context *pipe, struct
>> cso_context *cso)
>>
>>      LIST_INITHEAD(&hud->pane_list);
>>
>> +   /* setup sig handler once for all hud contexts */
>> +   if (!sig_handled) {
>> +      action.sa_sigaction = &signal_visible_handler;
>> +      action.sa_flags = SA_SIGINFO;
>> +
>> +      if (signo < 1 || signo >= NSIG)
>> +         fprintf(stderr, "gallium_hud: invalid signal %ld\n", signo);
>> +      else if (sigaction(signo, &action, NULL) < 0)
>> +         fprintf(stderr, "gallium_hud: unable to set handler for signal
>> %ld\n", signo);
>
>
> Can you put a fflush(stderr) call here?  Windows doesn't always immediately
> flush stdout/stderr output to the terminal.

Just directly after both of the conditions? See v6.

>
> -Brian
>
>
>> +
>> +      sig_handled = TRUE;
>> +   }
>> +
>>      hud_parse_env_var(hud, env);
>>      return hud;
>>   }
>>
>