🎉 Start incinerate effect at pointer location

kwin/incinerate/onAnimationBegin.js

@@ -1,4 +1,9 @@
 // This part is automatically included in the effect's source during the build process.
 // The code below is called whenever a window is closed or opened.
 
-effect.setUniform(this.shader, 'uSeed', [Math.random(), Math.random()]);
+let seed     = [Math.random(), Math.random()];
+let startPos = seed[0] > seed[1] ? [seed[0], Math.floor(seed[1] + 0.5)] :
+                                   [Math.floor(seed[0] + 0.5), seed[1]];
+
+effect.setUniform(this.shader, 'uSeed', seed);
+effect.setUniform(this.shader, 'uStartPos', startPos);

resources/shaders/incinerate.frag

@@ -17,6 +17,7 @@ uniform vec2 uSeed;
 uniform vec3 uColor;
 uniform float uScale;
 uniform float uTurbulence;
+uniform vec2 uStartPos;
 
 // This maps a given value in [0..1] to a color from the rgba color ramp
 // [transparent black ... semi-transparent uColor ... opaque white].
@@ -75,11 +76,8 @@ void main() {
 
   // Now we compute a 2D gradient in [0..1] which covers the entire window. The dark
   // regions will be burned first, the bright regions in the end. We mix a radial gradient
-  // with some noise. The center of the radial gradient is positioned somewhere at the
+  // with some noise. The center of the radial gradient is positioned at uStartPos.
-  // window boundary.
+  float circle = length(iTexCoord - uStartPos);
-  vec2 center  = uSeed.x > uSeed.y ? vec2(uSeed.x, floor(uSeed.y + 0.5))
-                                   : vec2(floor(uSeed.x + 0.5), uSeed.y);
-  float circle = length(iTexCoord - center);
 
   vec2 uv = iTexCoord / uScale * uSize / 1.5;
   float smokeNoise =

resources/ui/gtk3/Incinerate.ui

@@ -181,6 +181,68 @@
               </object>
             </child>
 
+            <child>
+              <object class="GtkListBoxRow">
+                <property name="margin-start">10</property>
+                <property name="margin-end">10</property>
+                <property name="margin-top">10</property>
+                <property name="margin-bottom">10</property>
+                <property name="activatable">0</property>
+                <child>
+                  <object class="GtkBox">
+                    <child>
+                      <object class="GtkBox">
+                        <property name="orientation">vertical</property>
+                        <property name="spacing">3</property>
+                        <child>
+                          <object class="GtkLabel">
+                            <property name="label" translatable="yes">Start at Pointer</property>
+                            <property name="xalign">0</property>
+                            <property name="halign">start</property>
+                            <property name="valign">center</property>
+                            <property name="hexpand">1</property>
+                          </object>
+                        </child>
+                        <child>
+                          <object class="GtkLabel">
+                            <property name="label" translatable="yes">If disabled, a random location will be chosen.</property>
+                            <property name="xalign">0</property>
+                            <property name="halign">start</property>
+                            <property name="valign">center</property>
+                            <property name="hexpand">1</property>
+                            <style>
+                              <class name="dim-label" />
+                              <class name="caption" />
+                            </style>
+                          </object>
+                        </child>
+                      </object>
+                    </child>
+                    <child>
+                      <object class="GtkSwitch" id="incinerate-use-pointer">
+                        <property name="halign">end</property>
+                        <property name="valign">center</property>
+                      </object>
+                    </child>
+                    <child>
+                      <object class="GtkButton" id="reset-incinerate-use-pointer">
+                        <child>
+                          <object class="GtkImage">
+                            <property name="icon-name">edit-clear-symbolic</property>
+                            <property name="icon-size">1</property>
+                          </object>
+                        </child>
+                        <property name="tooltip-text" translatable="yes">Reset to Default Value</property>
+                        <style>
+                          <class name="flat" />
+                        </style>
+                      </object>
+                    </child>
+                  </object>
+                </child>
+              </object>
+            </child>
+
             <child>
               <object class="GtkListBoxRow">
                 <property name="margin-start">10</property>

resources/ui/gtk4/Incinerate.ui

@@ -152,6 +152,59 @@
               </object>
             </child>
 
+            <child>
+              <object class="GtkListBoxRow">
+                <property name="activatable">0</property>
+                <child>
+                  <object class="GtkBox">
+                    <child>
+                      <object class="GtkBox">
+                        <property name="orientation">vertical</property>
+                        <property name="spacing">3</property>
+                        <child>
+                          <object class="GtkLabel">
+                            <property name="label" translatable="yes">Start at Pointer</property>
+                            <property name="xalign">0</property>
+                            <property name="halign">start</property>
+                            <property name="valign">center</property>
+                            <property name="hexpand">1</property>
+                          </object>
+                        </child>
+                        <child>
+                          <object class="GtkLabel">
+                            <property name="label" translatable="yes">If disabled, a random location will be chosen.</property>
+                            <property name="xalign">0</property>
+                            <property name="halign">start</property>
+                            <property name="valign">center</property>
+                            <property name="hexpand">1</property>
+                            <style>
+                              <class name="dim-label" />
+                              <class name="caption" />
+                            </style>
+                          </object>
+                        </child>
+                      </object>
+                    </child>
+                    <child>
+                      <object class="GtkSwitch" id="incinerate-use-pointer">
+                        <property name="halign">end</property>
+                        <property name="valign">center</property>
+                      </object>
+                    </child>
+                    <child>
+                      <object class="GtkButton" id="reset-incinerate-use-pointer">
+                        <property name="icon-name">edit-clear-symbolic</property>
+                        <property name="tooltip-text" translatable="yes">Reset to Default Value</property>
+                        <style>
+                          <class name="flat" />
+                        </style>
+                      </object>
+                    </child>
+                  </object>
+                </child>
+              </object>
+            </child>
+
             <child>
               <object class="GtkListBoxRow">
                 <property name="activatable">0</property>

schemas/org.gnome.shell.extensions.burn-my-windows.gschema.xml

@@ -371,6 +371,12 @@
       <description>The color of the effect.</description>
     </key>
 
+    <key name="incinerate-use-pointer" type="b">
+      <default>true</default>
+      <summary>Incinerate Use Pointer</summary>
+      <description>Use the pointer location for the incinerate effect.</description>
+    </key>
+
     <!-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -->
     <!-- Energize A Options                                                            -->
     <!-- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -->

src/Incinerate.js

@@ -47,22 +47,65 @@ var Incinerate = class {
       shader._uColor      = shader.get_uniform_location('uColor');
       shader._uScale      = shader.get_uniform_location('uScale');
       shader._uTurbulence = shader.get_uniform_location('uTurbulence');
+      shader._uStartPos   = shader.get_uniform_location('uStartPos');
 
       // Write all uniform values at the start of each animation.
-      shader.connect('begin-animation', (shader, settings) => {
+      shader.connect('begin-animation', (shader, settings, forOpening, actor) => {
-        const c = Clutter.Color.from_string(settings.get_string('incinerate-color'))[1];
-
         // If we are currently performing integration test, the animation uses a fixed
         // seed.
         const testMode = settings.get_boolean('test-mode');
+        let seed       = [testMode ? 0 : Math.random(), testMode ? 0 : Math.random()];
+
+        // If this option is set, we use the mouse pointer position. Because the actor
+        // position may change after the begin-animation signal is called, we set the
+        // uStartPos uniform during the update callback.
+        if (settings.get_boolean('incinerate-use-pointer')) {
+          this._startPointerPos = global.get_pointer();
+          this._actor           = actor;
+
+        } else {
+          // Else, a random position along the window boundary is used as start position
+          // for the incinerate effect.
+          let startPos = seed[0] > seed[1] ? [seed[0], Math.floor(seed[1] + 0.5)] :
+                                             [Math.floor(seed[0] + 0.5), seed[1]];
+
+          shader.set_uniform_float(shader._uStartPos, 2, startPos);
+
+          this._startPointerPos = null;
+        }
+
+        const c = Clutter.Color.from_string(settings.get_string('incinerate-color'))[1];
 
         // clang-format off
-        shader.set_uniform_float(shader._uSeed,  2, [testMode ? 0 : Math.random(), testMode ? 0 : Math.random()]);
+        shader.set_uniform_float(shader._uSeed,       2, seed);
-        shader.set_uniform_float(shader._uColor, 3, [c.red / 255, c.green / 255, c.blue / 255]);
+        shader.set_uniform_float(shader._uColor,      3, [c.red / 255, c.green / 255, c.blue / 255]);
-        shader.set_uniform_float(shader._uScale, 1, [settings.get_double('incinerate-scale')]);
+        shader.set_uniform_float(shader._uScale,      1, [settings.get_double('incinerate-scale')]);
         shader.set_uniform_float(shader._uTurbulence, 1, [settings.get_double('incinerate-turbulence')]);
         // clang-format on
       });
+
+      // If the mouse pointer position is used as start position, we set the uStartPos
+      // uniform during the update callback as the actor position may not be set up
+      // properly before the begin animation callback.
+      shader.connect('update-animation', (shader) => {
+        if (this._startPointerPos) {
+          const [x, y]               = this._startPointerPos;
+          const [ok, localX, localY] = this._actor.transform_stage_point(x, y);
+
+          if (ok) {
+            let startPos = [
+              Math.max(0.0, Math.min(1.0, localX / this._actor.width)),
+              Math.max(0.0, Math.min(1.0, localY / this._actor.height))
+            ];
+            shader.set_uniform_float(shader._uStartPos, 2, startPos);
+          }
+        }
+      });
+
+      // Make sure to drop the reference to the actor.
+      shader.connect('end-animation', (shader) => {
+        shader._actor = null;
+      });
     });
   }
 
@@ -100,6 +143,7 @@ var Incinerate = class {
     dialog.bindAdjustment('incinerate-animation-time');
     dialog.bindAdjustment('incinerate-scale');
     dialog.bindAdjustment('incinerate-turbulence');
+    dialog.bindSwitch('incinerate-use-pointer');
     dialog.bindColorButton('incinerate-color');
 
     // Finally, return the new settings page.