1 files changed, 25 insertions, 2 deletions

diff --git a/src/gui/Post.zig b/src/gui/Post.zig
index 06310b7f..602b2790 100644
--- a/src/gui/Post.zig
+++ b/src/gui/Post.zig
@@ -94,6 +94,8 @@ pub const Pass = struct {
     pipeline: ?*Pipeline = null,
     /// The SPIR-V revision `pipeline` was made from (shader_build.Pass).
     revision: u32 = 0,
+    /// It moves on its own (shader_build.Pass).
+    animated: bool = false,
 };
 
 passes: [max]Pass = @splat(.{}),
@@ -140,7 +142,7 @@ pub fn sync(post: *Post, gpa: std.mem.Allocator, device: *c.SDL_GPUDevice, forma
                 post.bloom_down = makePipeline(device, bloom_format, bloom_down_spv, 1, 1) catch null;
                 post.bloom_up = makePipeline(device, bloom_format, bloom_up_spv, 1, 1) catch null;
             }
-            next[i] = .{ .scene = scene, .level = entry.level, .pipeline = post.bundled.get(scene) };
+            next[i] = .{ .scene = scene, .level = entry.level, .pipeline = post.bundled.get(scene), .animated = entry.animated };
             continue;
         }
         // A file already in the chain keeps its pipeline and its path.
@@ -151,6 +153,7 @@ pub fn sync(post: *Post, gpa: std.mem.Allocator, device: *c.SDL_GPUDevice, forma
             break;
         } else next[i] = .{ .path = gpa.dupe(u8, entry.path) catch &.{} };
         const pass = &next[i];
+        pass.animated = entry.animated;
         if (pass.revision == entry.revision or entry.spirv.len == 0) continue;
         pass.revision = entry.revision;
         const made = makePipeline(device, format, entry.spirv, 1, 4) catch {
@@ -200,8 +203,14 @@ pub fn ready(post: *const Post) bool {
 }
 
 /// The chain redraws on its own (level A) as ShaderAnimation says.
+/// Only a pass that moves on its own (shader_build.Pass.animated) asks for
+/// frames while idle: a still one (Bloom, Vignette, Grain, a file that reads
+/// no clock) is drawn again only with a frame of the core's.
 pub fn animating(post: *const Post, mode: pardes.config.Runtime.ShaderAnimation) bool {
-    return post.ready() and switch (mode) {
+    const moving = for (post.passes[0..post.len]) |pass| {
+        if (pass.pipeline != null and pass.animated) break true;
+    } else false;
+    return moving and switch (mode) {
         .off => false,
         .on => post.uniforms.focus != 0,
         .always => true,
@@ -664,3 +673,17 @@ test "a moved cursor becomes the previous one, stamped with the time of the move
     try std.testing.expectEqual([4]f32{ 1.0 / 255.0, 2.0 / 255.0, 3.0 / 255.0, 1 }, post.uniforms.selection_foreground_color);
 }
 
+
+test "a still pass asks for no idle frames; one that reads the clock does" {
+    var post: Post = .{};
+    const fake: *Pipeline = @ptrFromInt(0x1000);
+    post.passes[0] = .{ .scene = .bloom, .level = 2, .pipeline = fake };
+    post.len = 1;
+    try std.testing.expect(!post.animating(.on) and !post.animating(.always));
+    post.passes[1] = .{ .scene = .crt, .level = 2, .pipeline = fake, .animated = true };
+    post.len = 2;
+    try std.testing.expect(post.animating(.on) and post.animating(.always) and !post.animating(.off));
+    // Unfocused, `on` rests.
+    post.uniforms.focus = 0;
+    try std.testing.expect(!post.animating(.on) and post.animating(.always));
+}