Fullscreen refresh rate improvements

Handle refresh rate as float in general, and add also extra
attributes (interlaced, doublescan) for video modes.

Make it possible to select exact mode (interlaced / doublescan modes
will not be selected), and allow close matches such as 49.5 Hz
for PAL 50 Hz.

gfx/display_servers/dispserv_kms.c

@@ -123,6 +123,8 @@ static void *kms_display_server_get_resolution_list(
    unsigned curr_width               = 0;
    unsigned curr_height              = 0;
    unsigned curr_bpp                 = 0;
+   bool curr_interlaced              = false;
+   bool curr_dblscan                 = false;
    float curr_refreshrate            = 0;
    unsigned curr_orientation         = 0;
    struct video_display_config *conf = NULL;
@@ -134,6 +136,8 @@ static void *kms_display_server_get_resolution_list(
       curr_width       = g_drm_mode->hdisplay;
       curr_height      = g_drm_mode->vdisplay;
       curr_bpp         = 32;
+      curr_interlaced  = (g_drm_mode->flags & DRM_MODE_FLAG_INTERLACE) ? true : false;
+      curr_dblscan     = (g_drm_mode->flags & DRM_MODE_FLAG_DBLSCAN)   ? true : false;
    }
 
    *len = g_drm_connector->count_modes;
@@ -147,13 +151,18 @@ static void *kms_display_server_get_resolution_list(
       conf[j].height      = g_drm_connector->modes[i].vdisplay;
       conf[j].bpp         = 32;
       conf[j].refreshrate = floor(drm_calc_refresh_rate(&g_drm_connector->modes[i]));
+      conf[j].refreshrate_float = drm_calc_refresh_rate(&g_drm_connector->modes[i]);
+      conf[j].interlaced  = (g_drm_connector->modes[i].flags & DRM_MODE_FLAG_INTERLACE) ? true : false;
+      conf[j].dblscan     = (g_drm_connector->modes[i].flags & DRM_MODE_FLAG_DBLSCAN)   ? true : false;
       conf[j].idx         = j;
       conf[j].current     = false;
 
       if (     (conf[j].width       == curr_width)
             && (conf[j].height      == curr_height)
             && (conf[j].bpp         == curr_bpp)
-            && (drm_calc_refresh_rate(&g_drm_connector->modes[i]) == curr_refreshrate)
+            && (conf[j].refreshrate_float == curr_refreshrate)
+            && (conf[j].interlaced  == curr_interlaced)
+            && (conf[j].dblscan     == curr_dblscan)
          )
          conf[j].current  = true;
       j++;

gfx/display_servers/dispserv_win32.c

@@ -356,6 +356,7 @@ static void *win32_display_server_get_resolution_list(
 #if _WIN32_WINNT >= 0x0500
    unsigned curr_orientation         = 0;
 #endif
+   bool curr_interlaced              = false;
    struct video_display_config *conf = NULL;
 
    if (win32_get_video_output(&dm, -1, sizeof(dm)))
@@ -367,6 +368,7 @@ static void *win32_display_server_get_resolution_list(
 #if _WIN32_WINNT >= 0x0500
       curr_orientation               = dm.dmDisplayOrientation;
 #endif
+      curr_interlaced                = (dm.dmDisplayFlags & DM_INTERLACED) ? true : false;
    }
 
    for (i = 0; win32_get_video_output(&dm, i, sizeof(dm)); i++)
@@ -403,13 +405,18 @@ static void *win32_display_server_get_resolution_list(
       conf[j].height      = dm.dmPelsHeight;
       conf[j].bpp         = dm.dmBitsPerPel;
       conf[j].refreshrate = dm.dmDisplayFrequency;
+      /* It may be possible to get exact refresh rate via different API - for now, it is integer only */
+      conf[j].refreshrate_float = 0.0f;
       conf[j].idx         = j;
       conf[j].current     = false;
+      conf[j].interlaced  = (dm.dmDisplayFlags & DM_INTERLACED) ? true : false;
+      conf[j].dblscan     = false; /* no flag for doublescan on this platform */
 
       if (     (conf[j].width       == curr_width)
             && (conf[j].height      == curr_height)
             && (conf[j].bpp         == curr_bpp)
             && (conf[j].refreshrate == curr_refreshrate)
+            && (conf[j].interlaced  == curr_interlaced)
          )
          conf[j].current  = true;
 

gfx/video_display_server.h

@@ -39,6 +39,9 @@ typedef struct video_display_config
    unsigned refreshrate;
    unsigned idx;
    bool current;
+   bool interlaced;
+   bool dblscan;
+   float refreshrate_float;
 } video_display_config_t;
 
 typedef struct video_display_server

gfx/video_driver.c

@@ -1214,9 +1214,14 @@ bool video_display_server_has_refresh_rate(float hz)
 
       for (i = 0; i < size && !rate_exists; i++)
       {
-         if (   (video_list[i].width       == video_driver_width)
-             && (video_list[i].height      == video_driver_height)
-             && (video_list[i].refreshrate == floor(hz)))
+         /* Float difference added to enable 49.95Hz modelines for PAL. *
+          * Actual mode selection will be done in context driver,       *
+          * with some logic in video_switch_refresh_rate_maybe          *   
+          * and in action_cb_push_dropdown_item_resolution              */
+         if (   (video_list[i].width        == video_driver_width)
+             && (video_list[i].height       == video_driver_height)
+             && ((video_list[i].refreshrate == floor(hz)) ||
+                 (fabsf(video_list[i].refreshrate_float - hz) < 0.06f)))
             rate_exists = true;
       }
 

menu/cbs/menu_cbs_ok.c

@@ -15,6 +15,7 @@
  *  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <math.h>
 #include <compat/strl.h>
 #include <array/rbuf.h>
 #include <file/file_path.h>
@@ -6928,7 +6929,7 @@ int action_cb_push_dropdown_item_resolution(const char *path,
    char *pch            = NULL;
    unsigned width       = 0;
    unsigned height      = 0;
-   unsigned refreshrate = 0;
+   float refreshrate    = 0.0f;
 
    strlcpy(str, path, sizeof(str));
    pch            = strtok(str, "x");
@@ -6939,10 +6940,10 @@ int action_cb_push_dropdown_item_resolution(const char *path,
       height      = (unsigned)strtoul(pch, NULL, 0);
    pch            = strtok(NULL, "(");
    if (pch)
-      refreshrate = (unsigned)strtoul(pch, NULL, 0);
+      refreshrate = (float)strtod(pch, NULL);
 
    if (video_display_server_set_resolution(width, height,
-         refreshrate, (float)refreshrate, 0, 0, 0, 0))
+         floor(refreshrate), refreshrate, 0, 0, 0, 0))
    {
       settings_t *settings = config_get_ptr();
 #ifdef _MSC_VER
@@ -6954,7 +6955,7 @@ int action_cb_push_dropdown_item_resolution(const char *path,
       float refresh_exact  = refreshrate;
 
       /* 59 Hz is an inaccurate representation of the real value (59.94).
-       * And since we at this point only have the integer to work with,
+       * In case at this point we only have the integer to work with,
        * the exact float needs to be calculated for 'video_refresh_rate' */
       if (refreshrate == (60.0f * refresh_mod) - 1)
          refresh_exact = 59.94f * refresh_mod;

menu/menu_displaylist.c

@@ -8350,10 +8350,20 @@ unsigned menu_displaylist_build_list(
                for (i = 0; i < size; i++)
                {
                   char val_d[256], str[256];
-                  snprintf(str, sizeof(str), "%dx%d (%d Hz)",
+                  /* If there is exact refresh rate available, use it */
+                  if (video_list[i].refreshrate_float > 0.0f)
+                     snprintf(str, sizeof(str), "%dx%d (%.3f Hz)%s%s",
                         video_list[i].width,
                         video_list[i].height,
-                        video_list[i].refreshrate);
+                        video_list[i].refreshrate_float,
+                        video_list[i].interlaced ? "[i]":"",
+                        video_list[i].dblscan    ? "[d]":"");
+                  else
+                     snprintf(str, sizeof(str), "%dx%d (%d Hz)%s",
+                        video_list[i].width,
+                        video_list[i].height,
+                        video_list[i].refreshrate,
+                        video_list[i].interlaced ? "[i]":"");
                   snprintf(val_d, sizeof(val_d), "%d", i);
                   if (menu_entries_append(list,
                            str,