Speedup in basic HSV to RGB conversion. On AVR this takes us from from about 68,000 conversions/second to about 105,000 conversions/second.

1 files changed, 44 insertions, 28 deletions

diff --git a/hsv2rgb.cpp b/hsv2rgb.cpp
index 8ba642d4..49056d51 100644
--- a/hsv2rgb.cpp
+++ b/hsv2rgb.cpp
@@ -286,22 +286,22 @@ void hsv2rgb_rainbow( const CHSV& hsv, CRGB& rgb)
     // Level Y2 is a strong boost.
     const uint8_t Y1 = 1;
     const uint8_t Y2 = 0;
-
+    
     // G2: Whether to divide all greens by two.
     // Depends GREATLY on your particular LEDs
     const uint8_t G2 = 0;
-
+    
     // Gscale: what to scale green down by.
     // Depends GREATLY on your particular LEDs
     const uint8_t Gscale = 0;
-
-
+    
+    
     uint8_t hue = hsv.hue;
     uint8_t sat = hsv.sat;
     uint8_t val = hsv.val;
-
+    
     uint8_t offset = hue & 0x1F; // 0..31
-
+    
     // offset8 = offset * 8
     uint8_t offset8 = offset;
     {
@@ -319,11 +319,11 @@ void hsv2rgb_rainbow( const CHSV& hsv, CRGB& rgb)
         offset8 <<= 3;
 #endif
     }
-
+    
     uint8_t third = scale8( offset8, (256 / 3));
-
+    
     uint8_t r, g, b;
-
+    
     if( ! (hue & 0x80) ) {
         // 0XX
         if( ! (hue & 0x40) ) {
@@ -397,7 +397,7 @@ void hsv2rgb_rainbow( const CHSV& hsv, CRGB& rgb)
                 uint8_t twothirds = scale8( offset8, ((256 * 2) / 3));
                 g = K171 - twothirds;
                 b = K85  + twothirds;
-
+                
             } else {
                 // 101
                 //case 5: // B -> P
@@ -405,7 +405,7 @@ void hsv2rgb_rainbow( const CHSV& hsv, CRGB& rgb)
                 g = 0;
                 FORCE_REFERENCE(g);
                 b = K255 - third;
-
+                
             }
         } else {
             if( !  (hue & 0x20)  ) {
@@ -415,7 +415,7 @@ void hsv2rgb_rainbow( const CHSV& hsv, CRGB& rgb)
                 g = 0;
                 FORCE_REFERENCE(g);
                 b = K171 - third;
-
+                
             } else {
                 // 111
                 //case 7: // K -> R
@@ -423,37 +423,53 @@ void hsv2rgb_rainbow( const CHSV& hsv, CRGB& rgb)
                 g = 0;
                 FORCE_REFERENCE(g);
                 b = K85 - third;
-
+                
             }
         }
     }
-
+    
     // This is one of the good places to scale the green down,
     // although the client can scale green down as well.
     if( G2 ) g = g >> 1;
     if( Gscale ) g = scale8_video_LEAVING_R1_DIRTY( g, Gscale);
-
+    
     // Scale down colors if we're desaturated at all
     // and add the brightness_floor to r, g, and b.
     if( sat != 255 ) {
-
-        nscale8x3_video( r, g, b, sat);
-
-        uint8_t desat = 255 - sat;
-        desat = scale8( desat, desat);
-
-        uint8_t brightness_floor = desat;
-        r += brightness_floor;
-        g += brightness_floor;
-        b += brightness_floor;
+        if( sat == 0) {
+            r = 255; b = 255; g = 255;
+        } else {
+            //nscale8x3_video( r, g, b, sat);
+            if( r ) r = scale8_LEAVING_R1_DIRTY( r, sat) + 1;
+            if( g ) g = scale8_LEAVING_R1_DIRTY( g, sat) + 1;
+            if( b ) b = scale8_LEAVING_R1_DIRTY( b, sat) + 1;
+            cleanup_R1();
+            
+            uint8_t desat = 255 - sat;
+            desat = scale8( desat, desat);
+            
+            uint8_t brightness_floor = desat;
+            r += brightness_floor;
+            g += brightness_floor;
+            b += brightness_floor;
+        }
     }
-
+    
     // Now scale everything down if we're at value < 255.
     if( val != 255 ) {
+        
         val = scale8_video_LEAVING_R1_DIRTY( val, val);
-        nscale8x3_video( r, g, b, val);
+        if( val == 0 ) {
+            r=0; g=0; b=0;
+        } else {
+            // nscale8x3_video( r, g, b, val);
+            if( r ) r = scale8_LEAVING_R1_DIRTY( r, val) + 1;
+            if( g ) g = scale8_LEAVING_R1_DIRTY( g, val) + 1;
+            if( b ) b = scale8_LEAVING_R1_DIRTY( b, val) + 1;
+            cleanup_R1();
+        }
     }
-
+    
     // Here we have the old AVR "missing std X+n" problem again
     // It turns out that fixing it winds up costing more than
     // not fixing it.