diff --git a/retro/shaders/sharp-bilinear.slang b/retro/shaders/sharp-bilinear.slang
index 96c2112..1831675 100644
--- a/retro/shaders/sharp-bilinear.slang
+++ b/retro/shaders/sharp-bilinear.slang
@@ -1,5 +1,10 @@
 #version 450
 
+layout(push_constant) uniform Push
+{
+  float SHARP_BILINEAR_PRE_SCALE;
+} param;
+
 layout(std140, set = 0, binding = 0) uniform UBO
 {
    mat4 MVP;
@@ -9,15 +14,15 @@ layout(std140, set = 0, binding = 0) uniform UBO
 } global;
 
 /*
- * sharp-bilinear.cg
+ * sharp-bilinear.slang
  * Author: Themaister
  * License: Public domain
  * 
  * Does a bilinear stretch, with a preapplied Nx nearest-neighbor scale, giving a
  * sharper image than plain bilinear.
  */
- 
- #define SHARP_BILINEAR_PRE_SCALE 4.0
+
+#pragma parameter SHARP_BILINEAR_PRE_SCALE "Sharp Bilinear Prescale" 4.0 1.0 10.0 1.0
 
 #pragma stage vertex
 layout(location = 0) in vec4 Position;
@@ -40,13 +45,13 @@ void main()
    vec2 texel = vTexCoord * global.SourceSize.xy;
    vec2 texel_floored = floor(texel);
    vec2 s = fract(texel);
-   float region_range = 0.5 - 0.5 / SHARP_BILINEAR_PRE_SCALE;
+   float region_range = 0.5 - 0.5 / param.SHARP_BILINEAR_PRE_SCALE;
 
    // Figure out where in the texel to sample to get correct pre-scaled bilinear.
    // Uses the hardware bilinear interpolator to avoid having to sample 4 times manually.
 
    vec2 center_dist = s - 0.5;
-   vec2 f = (center_dist - clamp(center_dist, -region_range, region_range)) * SHARP_BILINEAR_PRE_SCALE + 0.5;
+   vec2 f = (center_dist - clamp(center_dist, -region_range, region_range)) * param.SHARP_BILINEAR_PRE_SCALE + 0.5;
 
    vec2 mod_texel = texel_floored + f;