2 files changed, 9 insertions, 3 deletions
diff --git a/shaders/post/crt.glsl b/shaders/post/crt.glsl
index 768157ef..970d61ee 100644
--- a/shaders/post/crt.glsl
+++ b/shaders/post/crt.glsl
@@ -69,9 +69,11 @@ void mainImage(out vec4 fragColor, in vec2 fragCoord) {
     // A beam is brightest on its line and falls off between lines; the
     // mask is three phosphor stripes a triad. Both average to one, so the
     // theme keeps its brightness.
-    float line = 0.5 + 0.5 * cos(fragCoord.y * TAU / SCAN_PERIOD_PX);
+    // Periods in logical pixels: the same look at any density.
+    float density = max(1.0, pardesScale);
+    float line = 0.5 + 0.5 * cos(fragCoord.y * TAU / (SCAN_PERIOD_PX * density));
     col *= 1.0 - scanStrength() * (line * line - 0.375) / 0.625;
-    col *= 1.0 + maskStrength() * cos(fragCoord.x * TAU / MASK_PERIOD_PX + vec3(0.0, TAU / 3.0, 2.0 * TAU / 3.0));
+    col *= 1.0 + maskStrength() * cos(fragCoord.x * TAU / (MASK_PERIOD_PX * density) + vec3(0.0, TAU / 3.0, 2.0 * TAU / 3.0));
 
     float vignette = 1.0 - vignetteStrength() * pow(clamp(r2 * 0.5, 0.0, 1.0), 1.6);
     float hum = 1.0 + humStrength() * sin((uv.y * 1.35 - iTime * HUM_HZ) * TAU);
diff --git a/shaders/post/prefix.glsl b/shaders/post/prefix.glsl
index e718a98f..7a50936e 100644
--- a/shaders/post/prefix.glsl
+++ b/shaders/post/prefix.glsl
@@ -41,10 +41,14 @@ layout(set = 3, binding = 0, std140) uniform Globals {
 
 // pardes's own: pardesOpaque is 1 when the window is opaque, so a pass
 // cannot punch holes in it through its alpha; pardesLevel is a bundled
-// pass's strength, 1 to 3 (`Crt 3`), and 0 for a user's file.
+// pass's strength, 1 to 3 (`Crt 3`), and 0 for a user's file; pardesScale
+// is the display's density (2 on a 2x screen), for a pass whose pattern is
+// in logical pixels. iResolution, fragCoord and iMouse stay in the display's
+// pixels, as ghostty's do.
 layout(set = 3, binding = 1, std140) uniform PardesPost {
     float pardesOpaque;
     float pardesLevel;
+    float pardesScale;
 };
 
 // A bundled pass's constant at levels 1, 2 and 3.