merged from fsm branch to get lots of updates

1 files changed, 25 insertions, 2 deletions

diff --git a/spaghetti-monster/fsm-ramping.c b/spaghetti-monster/fsm-ramping.c
index ee816dd..082f8c9 100644
--- a/spaghetti-monster/fsm-ramping.c
+++ b/spaghetti-monster/fsm-ramping.c
@@ -65,8 +65,31 @@ void set_level(uint8_t level) {
         // and a global tint value
         uint8_t brightness = pgm_read_byte(pwm1_levels + level);
         uint8_t warm_PWM, cool_PWM;
-        cool_PWM = (((uint16_t)tint * (uint16_t)brightness) + 127) / 255;
-        warm_PWM = brightness - cool_PWM;
+
+        // auto-tint modes
+        uint8_t mytint;
+        #if 1
+        // perceptual by ramp level
+        if (tint == 0) { mytint = 255 * (uint16_t)level / RAMP_SIZE; }
+        else if (tint == 255) { mytint = 255 - (255 * (uint16_t)level / RAMP_SIZE); }
+        #else
+        // linear with power level
+        //if (tint == 0) { mytint = brightness; }
+        //else if (tint == 255) { mytint = 255 - brightness; }
+        #endif
+        // stretch 1-254 to fit 0-255 range (hits every value except 98 and 198)
+        else { mytint = (tint * 100 / 99) - 1; }
+
+        // middle tints sag, so correct for that effect
+        uint16_t base_PWM = brightness;
+        // correction is only necessary when PWM is fast
+        if (level > HALFSPEED_LEVEL) {
+            base_PWM = brightness
+                     + ((((uint16_t)brightness) * 26 / 64) * triangle_wave(mytint) / 255);
+        }
+
+        cool_PWM = (((uint16_t)mytint * (uint16_t)base_PWM) + 127) / 255;
+        warm_PWM = base_PWM - cool_PWM;
 
         PWM1_LVL = warm_PWM;
         PWM2_LVL = cool_PWM;