Pass 'radius' to blur APIs instead of 'sigma'

Requires mutter!1908 first.

So now consumers of the clutter blur code don't have to know the
implementation is Gaussian and no longer need to convert the intended
blur radius to a sigma value.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1905>

diff --git a/js/ui/unlockDialog.js b/js/ui/unlockDialog.js
index 15ed61a5620642ff7d934aef5675d421a54231a8..62b6cc3dc94ac511f87a1a1cd2c3ed480d618d26 100644 (file)
--- a/js/ui/unlockDialog.js
+++ b/js/ui/unlockDialog.js
@@ -30,7 +30,7 @@ const FADE_OUT_TRANSLATION = 200;
 const FADE_OUT_SCALE = 0.3;
 
 const BLUR_BRIGHTNESS = 0.65;
-const BLUR_SIGMA = 45;
+const BLUR_RADIUS = 90;
 
 const SUMMARY_ICON_SIZE = 32;
 
@@ -668,7 +668,7 @@ export const UnlockDialog = GObject.registerClass({
             if (effect) {
                 effect.set({
                     brightness: BLUR_BRIGHTNESS,
-                    sigma: BLUR_SIGMA * themeContext.scale_factor,
+                    radius: BLUR_RADIUS * themeContext.scale_factor,
                 });
             }
         }

diff --git a/src/shell-blur-effect.c b/src/shell-blur-effect.c
index 4f2acc4b9d9f59125abc0adb25b7dc412a6474f2..7a3267f91b7d21b155f476fefbfd75c411b675ec 100644 (file)
--- a/src/shell-blur-effect.c
+++ b/src/shell-blur-effect.c
@@ -49,7 +49,7 @@ static const gchar *brightness_glsl =
 "  cogl_color_out.rgb *= brightness;                                       \n";
 
 #define MIN_DOWNSCALE_SIZE 256.f
-#define MAX_SIGMA 6.f
+#define MAX_RADIUS 12.f
 
 typedef enum
 {
@@ -84,14 +84,14 @@ struct _ShellBlurEffect
   ShellBlurMode mode;
   float downscale_factor;
   float brightness;
-  int sigma;
+  int radius;
 };
 
 G_DEFINE_TYPE (ShellBlurEffect, shell_blur_effect, CLUTTER_TYPE_EFFECT)
 
 enum {
   PROP_0,
-  PROP_SIGMA,
+  PROP_RADIUS,
   PROP_BRIGHTNESS,
   PROP_MODE,
   N_PROPS
@@ -276,18 +276,18 @@ clear_framebuffer_data (FramebufferData *fb_data)
 static float
 calculate_downscale_factor (float width,
                             float height,
-                            float sigma)
+                            float radius)
 {
   float downscale_factor = 1.0;
   float scaled_width = width;
   float scaled_height = height;
-  float scaled_sigma = sigma;
+  float scaled_radius = radius;
 
   /* This is the algorithm used by Firefox; keep downscaling until either the
    * blur radius is lower than the threshold, or the downscaled texture is too
    * small.
    */
-  while (scaled_sigma > MAX_SIGMA &&
+  while (scaled_radius > MAX_RADIUS &&
          scaled_width > MIN_DOWNSCALE_SIZE &&
          scaled_height > MIN_DOWNSCALE_SIZE)
     {
@@ -295,7 +295,7 @@ calculate_downscale_factor (float width,
 
       scaled_width = width / downscale_factor;
       scaled_height = height / downscale_factor;
-      scaled_sigma = sigma / downscale_factor;
+      scaled_radius = radius / downscale_factor;
     }
 
   return downscale_factor;
@@ -421,7 +421,7 @@ create_blur_nodes (ShellBlurEffect  *self,
 
   blur_node = clutter_blur_node_new (self->tex_width / self->downscale_factor,
                                      self->tex_height / self->downscale_factor,
-                                     self->sigma / self->downscale_factor);
+                                     self->radius / self->downscale_factor);
   clutter_paint_node_set_static_name (blur_node, "ShellBlurEffect (blur)");
   clutter_paint_node_add_child (brightness_node, blur_node);
   clutter_paint_node_add_rectangle (blur_node,
@@ -495,7 +495,7 @@ update_framebuffers (ShellBlurEffect     *self,
 
   clutter_actor_box_get_size (source_actor_box, &width, &height);
 
-  downscale_factor = calculate_downscale_factor (width, height, self->sigma);
+  downscale_factor = calculate_downscale_factor (width, height, self->radius);
 
   updated = update_actor_fbo (self, width, height, downscale_factor) &&
             update_brightness_fbo (self, width, height, downscale_factor);
@@ -615,7 +615,7 @@ shell_blur_effect_paint_node (ClutterEffect           *effect,
 
   g_assert (self->actor != NULL);
 
-  if (self->sigma > 0)
+  if (self->radius > 0)
     {
       g_autoptr (ClutterPaintNode) blur_node = NULL;
 
@@ -714,8 +714,8 @@ shell_blur_effect_get_property (GObject    *object,
 
   switch (prop_id)
     {
-    case PROP_SIGMA:
-      g_value_set_int (value, self->sigma);
+    case PROP_RADIUS:
+      g_value_set_int (value, self->radius);
       break;
 
     case PROP_BRIGHTNESS:
@@ -741,8 +741,8 @@ shell_blur_effect_set_property (GObject      *object,
 
   switch (prop_id)
     {
-    case PROP_SIGMA:
-      shell_blur_effect_set_sigma (self, g_value_get_int (value));
+    case PROP_RADIUS:
+      shell_blur_effect_set_radius (self, g_value_get_int (value));
       break;
 
     case PROP_BRIGHTNESS:
@@ -773,10 +773,10 @@ shell_blur_effect_class_init (ShellBlurEffectClass *klass)
 
   effect_class->paint_node = shell_blur_effect_paint_node;
 
-  properties[PROP_SIGMA] =
-    g_param_spec_int ("sigma",
-                      "Sigma",
-                      "Sigma",
+  properties[PROP_RADIUS] =
+    g_param_spec_int ("radius",
+                      "Radius",
+                      "Radius in pixels",
                       0, G_MAXINT, 0,
                       G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY);
 
@@ -802,7 +802,7 @@ static void
 shell_blur_effect_init (ShellBlurEffect *self)
 {
   self->mode = SHELL_BLUR_MODE_ACTOR;
-  self->sigma = 0;
+  self->radius = 0;
   self->brightness = 1.f;
 
   self->actor_fb.pipeline = create_base_pipeline ();
@@ -819,29 +819,29 @@ shell_blur_effect_new (void)
 }
 
 int
-shell_blur_effect_get_sigma (ShellBlurEffect *self)
+shell_blur_effect_get_radius (ShellBlurEffect *self)
 {
   g_return_val_if_fail (SHELL_IS_BLUR_EFFECT (self), -1);
 
-  return self->sigma;
+  return self->radius;
 }
 
 void
-shell_blur_effect_set_sigma (ShellBlurEffect *self,
-                             int              sigma)
+shell_blur_effect_set_radius (ShellBlurEffect *self,
+                              int              radius)
 {
   g_return_if_fail (SHELL_IS_BLUR_EFFECT (self));
 
-  if (self->sigma == sigma)
+  if (self->radius == radius)
     return;
 
-  self->sigma = sigma;
+  self->radius = radius;
   self->cache_flags &= ~BLUR_APPLIED;
 
   if (self->actor)
     clutter_effect_queue_repaint (CLUTTER_EFFECT (self));
 
-  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_SIGMA]);
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_RADIUS]);
 }
 
 float

diff --git a/src/shell-blur-effect.h b/src/shell-blur-effect.h
index a7486ccde09b169f4a7e4bca5447b1b771ca0585..a0b216a715e54407c8783b1a69c2d3cc6b89cd92 100644 (file)
--- a/src/shell-blur-effect.h
+++ b/src/shell-blur-effect.h
@@ -42,9 +42,9 @@ G_DECLARE_FINAL_TYPE (ShellBlurEffect, shell_blur_effect, SHELL, BLUR_EFFECT, Cl
 
 ShellBlurEffect *shell_blur_effect_new (void);
 
-int shell_blur_effect_get_sigma (ShellBlurEffect *self);
-void shell_blur_effect_set_sigma (ShellBlurEffect *self,
-                                  int              sigma);
+int shell_blur_effect_get_radius (ShellBlurEffect *self);
+void shell_blur_effect_set_radius (ShellBlurEffect *self,
+                                   int              radius);
 
 float shell_blur_effect_get_brightness (ShellBlurEffect *self);
 void shell_blur_effect_set_brightness (ShellBlurEffect *self,

diff --git a/src/st/st-private.c b/src/st/st-private.c
index 50a22f28dbc43659719d28df1ca1a87ed8087825..f7ea118a526de52148ba5e85f91945179def290f 100644 (file)
--- a/src/st/st-private.c
+++ b/src/st/st-private.c
@@ -391,7 +391,7 @@ _st_create_shadow_pipeline (StShadow    *shadow_spec,
   CoglPipeline *pipeline;
   CoglTexture *texture;
   float sampling_radius;
-  float sigma;
+  float radius;
   int src_height, dst_height;
   int src_width, dst_width;
   CoglPipeline *texture_pipeline;
@@ -403,9 +403,8 @@ _st_create_shadow_pipeline (StShadow    *shadow_spec,
   g_return_val_if_fail (shadow_spec != NULL, NULL);
   g_return_val_if_fail (src_texture != NULL, NULL);
 
-  sampling_radius = resource_scale * shadow_spec->blur;
-  sigma = sampling_radius / 2.f;
-  sampling_radius = ceilf (sampling_radius);
+  radius = resource_scale * shadow_spec->blur;
+  sampling_radius = ceilf (radius);
 
   src_width = cogl_texture_get_width (src_texture);
   src_height = cogl_texture_get_height (src_texture);
@@ -428,7 +427,7 @@ _st_create_shadow_pipeline (StShadow    *shadow_spec,
   cogl_framebuffer_orthographic (fb, 0, 0, dst_width, dst_height, 0, 1.0);
 
   /* Blur */
-  blur_node = clutter_blur_node_new (dst_width, dst_height, sigma);
+  blur_node = clutter_blur_node_new (dst_width, dst_height, radius);
   clutter_paint_node_add_rectangle (blur_node,
                                     &(ClutterActorBox) {
                                       0.f, 0.f,