Swapped fade point with a fade duration.

panels/cross-screen.toml

@@ -6,5 +6,5 @@ geometry = "1920x1080+960+0"
 geometry = "960x1080+2880+0"
 
 [state]
-duration   = 300
-fade_point = 250
+duration      = 300
+fade_duration = 50

panels/full.toml

@@ -2,5 +2,5 @@
 geometry = "1366x768+0+0"
 
 [state]
-duration   = 300
-fade_point = 250
+duration      = 300
+fade_duration = 50

panels/multiple.toml

@@ -5,8 +5,8 @@ geometry = "960x540+0+540"
 geometry = "960x1080+960+0"
 
 [state]
-duration   = 300
-fade_point = 250
+duration      = 300
+fade_duration = 50
 
 [shader]
 type     = "fade-out"

panels/quarter.toml

@@ -2,8 +2,8 @@
 geometry = "960x540+0+0"
 
 [state]
-duration   = 300
-fade_point = 250
+duration      = 300
+fade_duration = 50
 
 [shader]
 type     = "fade-white"

shaders/panels/fade/frag.wgsl

@@ -45,14 +45,17 @@ fn main(in: VertexOutput) -> FragOutput {
 	var out: FragOutput;
 
 	let p = uniforms.progress;
-	let f = uniforms.fade_point;
+	let f = uniforms.fade_duration;
 
-	let progress_prev = 1.0 - max((1.0 - p - f) / (3.0 - 2.0 * f), 0.0);
-	let progress_cur  = (p + 1.0 - f) / (3.0 - 2.0 * f);
-	let progress_next = max((p - f) / (3.0 - 2.0 * f), 0.0);
+	// Full duration an image is on screen (including the fades)
+	let d = 1.0 + 2.0 * f;
 
-	let alpha_prev = 0.5 * saturate(1.0 - (      p) / (1.0 - f));
-	let alpha_next = 0.5 * saturate(1.0 - (1.0 - p) / (1.0 - f));
+	let progress_prev = 1.0 - max((f - p) / d, 0.0);
+	let progress_cur  = (p + f) / d;
+	let progress_next = max((p - 1.0 + f) / d, 0.0);
+
+	let alpha_prev = 0.5 * saturate(1.0 - (      p) / f);
+	let alpha_next = 0.5 * saturate(1.0 - (1.0 - p) / f);
 	let alpha_cur  = 1.0 - max(alpha_prev, alpha_next);
 
 	// Sample the textures

shaders/panels/fade/uniforms.wgsl

@@ -12,7 +12,7 @@ struct Uniforms {
 	prev: ImageUniforms,
 	cur: ImageUniforms,
 	next: ImageUniforms,
-	fade_point: f32,
+	fade_duration: f32,
 	progress: f32,
 
 	// TODO: Reduce this repetition

zsw/src/panel.rs

@@ -57,7 +57,7 @@ impl Panel {
 	fn max_duration(images: &PanelImages, state: &PanelState) -> u64 {
 		match (images.cur.is_loaded(), images.next.is_loaded()) {
 			(false, false) => 0,
-			(true, false) => state.fade_point,
+			(true, false) => state.fade_duration,
 			(_, true) => state.duration,
 		}
 	}
@@ -73,7 +73,7 @@ impl Panel {
 		image_requester: &ImageRequester,
 	) {
 		match images.step_next(wgpu_shared, renderer_layouts).await {
-			Ok(()) => self.state.progress = self.state.duration.saturating_sub(self.state.fade_point),
+			Ok(()) => self.state.progress = self.state.duration.saturating_sub(self.state.fade_duration),
 			Err(()) => self.state.progress = Self::max_duration(images, &self.state),
 		}
 

zsw/src/panel/panels.rs

@@ -4,11 +4,11 @@
 use {
 	super::{Panel, PanelName, PanelShader, PanelState, ser},
 	crate::AppError,
+	app_error::Context,
 	futures::lock::Mutex,
 	std::{collections::HashMap, path::PathBuf, sync::Arc},
 	tokio::sync::OnceCell,
 	zsw_util::PathAppendExt,
-	app_error::Context,
 };
 
 /// Panel storage
@@ -61,10 +61,10 @@ impl Panels {
 				// Finally convert it
 				let geometries = panel.geometries.into_iter().map(|geometry| geometry.geometry).collect();
 				let state = PanelState {
-					paused:     false,
-					progress:   0,
-					duration:   panel.state.duration,
-					fade_point: panel.state.fade_point,
+					paused:        false,
+					progress:      0,
+					duration:      panel.state.duration,
+					fade_duration: panel.state.fade_duration,
 				};
 
 				// Get the shader

zsw/src/panel/renderer.rs

@@ -12,6 +12,7 @@ use {
 	self::uniform::PanelImageUniforms,
 	super::{Panel, PanelImage, PanelImages, PanelName, Panels},
 	crate::{config_dirs::ConfigDirs, panel::PanelGeometry},
+	app_error::Context,
 	cgmath::Vector2,
 	core::{
 		future::Future,
@@ -27,9 +28,8 @@ use {
 	tokio::fs,
 	wgpu::{naga, util::DeviceExt},
 	winit::dpi::PhysicalSize,
-	zsw_util::Rect,
+	zsw_util::{AppError, Rect},
 	zsw_wgpu::{FrameRender, WgpuRenderer, WgpuShared},
-	app_error::Context, zsw_util::AppError,
 };
 
 /// Panels renderer layouts
@@ -265,7 +265,7 @@ impl PanelsRenderer {
 			write_uniforms(bytemuck::bytes_of(&$uniforms))
 		}
 
-		let fade_point = panel.state.fade_point_norm();
+		let fade_duration = panel.state.fade_duration_norm();
 		let progress = panel.state.progress_norm();
 		match panel.shader {
 			PanelShader::None { background_color } => write_uniforms!(uniform::None {
@@ -277,7 +277,7 @@ impl PanelsRenderer {
 				prev,
 				cur,
 				next,
-				fade_point,
+				fade_duration,
 				progress,
 				_unused: [0; 2],
 			}),
@@ -286,7 +286,7 @@ impl PanelsRenderer {
 				prev,
 				cur,
 				next,
-				fade_point,
+				fade_duration,
 				progress,
 				strength,
 				_unused: 0,
@@ -296,7 +296,7 @@ impl PanelsRenderer {
 				prev,
 				cur,
 				next,
-				fade_point,
+				fade_duration,
 				progress,
 				strength,
 				_unused: 0,
@@ -306,7 +306,7 @@ impl PanelsRenderer {
 				prev,
 				cur,
 				next,
-				fade_point,
+				fade_duration,
 				progress,
 				strength,
 				_unused: 0,

zsw/src/panel/renderer/uniform.rs

@@ -55,12 +55,12 @@ pub struct None {
 #[derive(Zeroable, Pod)]
 #[repr(C)]
 pub struct Fade {
-	pub pos_matrix: Matrix4x4,
-	pub prev:       PanelImageUniforms,
-	pub cur:        PanelImageUniforms,
-	pub next:       PanelImageUniforms,
-	pub fade_point: f32,
-	pub progress:   f32,
+	pub pos_matrix:    Matrix4x4,
+	pub prev:          PanelImageUniforms,
+	pub cur:           PanelImageUniforms,
+	pub next:          PanelImageUniforms,
+	pub fade_duration: f32,
+	pub progress:      f32,
 
 	pub _unused: [u32; 2],
 }
@@ -70,13 +70,13 @@ pub struct Fade {
 #[derive(Zeroable, Pod)]
 #[repr(C)]
 pub struct FadeWhite {
-	pub pos_matrix: Matrix4x4,
-	pub prev:       PanelImageUniforms,
-	pub cur:        PanelImageUniforms,
-	pub next:       PanelImageUniforms,
-	pub fade_point: f32,
-	pub progress:   f32,
-	pub strength:   f32,
+	pub pos_matrix:    Matrix4x4,
+	pub prev:          PanelImageUniforms,
+	pub cur:           PanelImageUniforms,
+	pub next:          PanelImageUniforms,
+	pub fade_duration: f32,
+	pub progress:      f32,
+	pub strength:      f32,
 
 	pub _unused: u32,
 }
@@ -86,13 +86,13 @@ pub struct FadeWhite {
 #[derive(Zeroable, Pod)]
 #[repr(C)]
 pub struct FadeOut {
-	pub pos_matrix: Matrix4x4,
-	pub prev:       PanelImageUniforms,
-	pub cur:        PanelImageUniforms,
-	pub next:       PanelImageUniforms,
-	pub fade_point: f32,
-	pub progress:   f32,
-	pub strength:   f32,
+	pub pos_matrix:    Matrix4x4,
+	pub prev:          PanelImageUniforms,
+	pub cur:           PanelImageUniforms,
+	pub next:          PanelImageUniforms,
+	pub fade_duration: f32,
+	pub progress:      f32,
+	pub strength:      f32,
 
 	pub _unused: u32,
 }
@@ -102,13 +102,13 @@ pub struct FadeOut {
 #[derive(Zeroable, Pod)]
 #[repr(C)]
 pub struct FadeIn {
-	pub pos_matrix: Matrix4x4,
-	pub prev:       PanelImageUniforms,
-	pub cur:        PanelImageUniforms,
-	pub next:       PanelImageUniforms,
-	pub fade_point: f32,
-	pub progress:   f32,
-	pub strength:   f32,
+	pub pos_matrix:    Matrix4x4,
+	pub prev:          PanelImageUniforms,
+	pub cur:           PanelImageUniforms,
+	pub next:          PanelImageUniforms,
+	pub fade_duration: f32,
+	pub progress:      f32,
+	pub strength:      f32,
 
 	pub _unused: u32,
 }

zsw/src/panel/ser.rs

@@ -29,8 +29,8 @@ pub struct PanelGeometry {
 #[derive(Debug)]
 #[derive(serde::Serialize, serde::Deserialize)]
 pub struct PanelState {
-	pub duration:   u64,
-	pub fade_point: u64,
+	pub duration:      u64,
+	pub fade_duration: u64,
 }
 
 /// Configuration shader

zsw/src/panel/state.rs

@@ -12,8 +12,8 @@ pub struct PanelState {
 	/// Duration (in frames)
 	pub duration: u64,
 
-	/// Fade point (in frames)
-	pub fade_point: u64,
+	/// Fade duration (in frames)
+	pub fade_duration: u64,
 }
 
 impl PanelState {
@@ -24,9 +24,9 @@ impl PanelState {
 		self.progress as f32 / self.duration as f32
 	}
 
-	/// Returns the fade point normalized
-	pub fn fade_point_norm(&self) -> f32 {
+	/// Returns the fade duration normalized
+	pub fn fade_duration_norm(&self) -> f32 {
 		// Note: Image progress is linear throughout the full cycle
-		self.fade_point as f32 / self.duration as f32
+		self.fade_duration as f32 / self.duration as f32
 	}
 }

zsw/src/settings_menu.rs

@@ -127,19 +127,21 @@ fn draw_panels_editor(ui: &mut egui::Ui, shared: &Shared, shared_window: &Shared
 				let cur_max = match panels_images.get(&panel.name) {
 					Some(panel_images) => match (panel_images.cur.is_loaded(), panel_images.next.is_loaded()) {
 						(false, false) => 0,
-						(true, false) => panel.state.fade_point,
+						(true, false) => panel.state.fade_duration,
 						(_, true) => panel.state.duration,
 					},
 					None => 0,
 				};
+
+				// TODO: This should be done elsewhere.
 				panel.state.progress = panel.state.progress.clamp(0, cur_max);
 			});
 
 			ui.horizontal(|ui| {
-				ui.label("Fade Point");
-				let min = panel.state.duration / 2;
-				let max = panel.state.duration;
-				egui::Slider::new(&mut panel.state.fade_point, min..=max)
+				ui.label("Fade Duration");
+				let min = 0;
+				let max = panel.state.duration / 2;
+				egui::Slider::new(&mut panel.state.fade_duration, min..=max)
 					.clamping(egui::SliderClamping::Edits)
 					.ui(ui);
 			});