diff options
| author | lonkaars <loek@pipeframe.xyz> | 2021-08-10 10:20:18 +0200 |
|---|---|---|
| committer | lonkaars <loek@pipeframe.xyz> | 2021-08-10 10:20:18 +0200 |
| commit | 5b77b28816ee8923b08abf19222be1716f656484 (patch) | |
| tree | 390eb82bd44a4394592f7e6f3f465e0acbd5e927 | |
| parent | abf982ec977c6352f6dbf3eed6fc27f11d200836 (diff) | |
added brightness curve correction
this should display colors more accurately to the color on a display
| -rw-r--r-- | main/main.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/main/main.c b/main/main.c index 27bb6fc..ebfb8c7 100644 --- a/main/main.c +++ b/main/main.c @@ -1,4 +1,5 @@ #include <sys/param.h> +#include <math.h> #include "esp_event.h" #include "esp_log.h" @@ -14,12 +15,17 @@ #include <esp_http_server.h> +// channel configuration #define GPIO_OUTPUT_CHANNEL_RED 0 #define GPIO_OUTPUT_CHANNEL_GREEN 0 #define GPIO_OUTPUT_CHANNEL_BLUE 2 +// pwm frequency #define PWM_PERIOD 1000 +// raises the brigtness value from 0-1 to this power +#define BRIGHTNESS_CURVE_CORRECTION 3 + static const char *TAG = "rgbstrip"; int color[3]; static httpd_handle_t server = NULL; @@ -31,9 +37,9 @@ uint32_t duties[] = {0, 0, 0}; float phase[] = {0, 0, 0}; void update_strip() { - duties[0] = PWM_PERIOD - (int)((float)(PWM_PERIOD * color[0]) / 0xff); - duties[1] = PWM_PERIOD - (int)((float)(PWM_PERIOD * color[1]) / 0xff); - duties[2] = PWM_PERIOD - (int)((float)(PWM_PERIOD * color[2]) / 0xff); + duties[0] = PWM_PERIOD - (int)( PWM_PERIOD * pow( (float)color[0] / 0xff, BRIGHTNESS_CURVE_CORRECTION ) ); + duties[1] = PWM_PERIOD - (int)( PWM_PERIOD * pow( (float)color[1] / 0xff, BRIGHTNESS_CURVE_CORRECTION ) ); + duties[2] = PWM_PERIOD - (int)( PWM_PERIOD * pow( (float)color[2] / 0xff, BRIGHTNESS_CURVE_CORRECTION ) ); pwm_set_duties(duties); pwm_start(); } |