Added GLSL sampling modes

shaders/smooth_parameters.glsl

@@ -13,10 +13,25 @@
    - circular     heavily rounded points
    - sinusoidal   rounded at both low and high weighted values
                     like a sine wave
-   - linear       not rounded at all, just use linear distance
+   - linear       not rounded at all; linear distance
    */
 #define ROUND_FORMULA sinusoidal
 
+/* The sampling mode for processing raw FFT input:
+   
+   - average     averages all the inputs in the sample range for
+                   a given point. Produces smooth output, but peaks
+                   are not well represented
+   - maximum     obtains the best value from the closest peak in
+                   the sample range. Very accurate peaks, but
+                   output is jagged and sporadic.
+   - hybrid      uses the results from both `average` and `maximum`
+                   with the weight provided in `SAMPLE_HYBRID_WEIGHT` */
+#define SAMPLE_MODE average
+/* Weight should be provided in the range (0, 1). Higher values favour
+   averaged results. `hybrid` mode only. */
+#define SAMPLE_HYBRID_WEIGHT 0.65
+
 /* Factor used to scale frequencies. Lower values allows lower
    frequencies to occupy more space. */
 #define SAMPLE_SCALE 8

shaders/util/smooth.glsl

@@ -21,6 +21,10 @@
 /* take value x that scales linearly between [0, 1) and return its circlar curve */
 #define circular(x) sqrt(1 - (((x) - 1) * ((x) - 1)))
 
+#define average 0
+#define maximum 1
+#define hybrid 2
+
 float scale_audio(float idx) {
     return -log((-(SAMPLE_RANGE) * idx) + 1) / (SAMPLE_SCALE);
 }
@@ -32,20 +36,42 @@ float iscale_audio(float idx) {
 /* Note: the SMOOTH_FACTOR macro is defined by GLava itself, from `#request setsmoothfactor`*/
 
 float smooth_audio(in sampler1D tex, int tex_sz, highp float idx) {
+    
     #if PRE_SMOOTHED_AUDIO < 1
     float
         smin = scale_audio(clamp(idx - SMOOTH_FACTOR, 0, 1)) * tex_sz,
-        smax  = scale_audio(clamp(idx + SMOOTH_FACTOR, 0, 1)) * tex_sz,
-        avg = 0, s, weight = 0;
-    float m = ((smax - smin) / 2.0F);
+        smax = scale_audio(clamp(idx + SMOOTH_FACTOR, 0, 1)) * tex_sz;
+    float m = ((smax - smin) / 2.0F), s, w;
     float rm = smin + m; /* middle */
+    #if SAMPLE_MODE == average
+    float avg = 0, weight = 0;
     for (s = smin; s <= smax; s += 1.0F) {
-        float w = ROUND_FORMULA(clamp((m - abs(rm - s)) / m, 0, 1));
+        w = ROUND_FORMULA(clamp((m - abs(rm - s)) / m, 0, 1));
         weight += w;
         avg += texelFetch(tex, int(round(s)), 0).r * w;
     }
     avg /= weight;
     return avg;
+    #elif SAMPLE_MODE == hybrid
+    float vmax = 0, avg = 0, weight = 0, v;
+    for (s = smin; s < smax; s += 1.0F) {
+        w = ROUND_FORMULA(clamp((m - abs(rm - s)) / m, 0, 1));
+        weight += w;
+        v = texelFetch(tex, int(round(s)), 0).r * w;
+        avg += v;
+        if (vmax < v)
+            vmax = v;
+    }
+    return (vmax * (1 - SAMPLE_HYBRID_WEIGHT)) + ((avg / weight) * SAMPLE_HYBRID_WEIGHT);
+    #elif SAMPLE_MODE == maximum
+    float vmax = 0, v;
+    for (s = smin; s < smax; s += 1.0F) {
+        w = texelFetch(tex, int(round(s)), 0).r * ROUND_FORMULA(clamp((m - abs(rm - s)) / m, 0, 1));
+        if (vmax < w)
+            vmax = w;
+    }
+    return vmax;
+    #endif
     #else
     return texelFetch(tex, int(round(idx * tex_sz)), 0).r;
     #endif