diff --git a/lcd_backlight.c b/lcd_backlight.c new file mode 100644 index 00000000..70187d1e --- /dev/null +++ b/lcd_backlight.c @@ -0,0 +1,85 @@ +/* +The MIT License (MIT) + +Copyright (c) 2016 Fred Sundvik + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. +*/ + +#include "lcd_backlight.h" +#include + +static uint8_t current_hue = 0x00; +static uint8_t current_saturation = 0x00; +static uint8_t current_intensity = 0xFF; +static uint8_t current_brightness = 0x7F; + +void lcd_backlight_init(void) { + lcd_backlight_hal_init(); + lcd_backlight_color(current_hue, current_saturation, current_intensity); +} + +// This code is based on Brian Neltner's blogpost and example code +// "Why every LED light should be using HSI colorspace". +// http://blog.saikoled.com/post/43693602826/why-every-led-light-should-be-using-hsi +static void hsi_to_rgb(float h, float s, float i, uint16_t* r_out, uint16_t* g_out, uint16_t* b_out) { + unsigned int r, g, b; + h = fmodf(h, 360.0f); // cycle h around to 0-360 degrees + h = 3.14159f * h / 180.0f; // Convert to radians. + s = s > 0.0f ? (s < 1.0f ? s : 1.0f) : 0.0f; // clamp s and i to interval [0,1] + i = i > 0.0f ? (i < 1.0f ? i : 1.0f) : 0.0f; + + // Math! Thanks in part to Kyle Miller. + if(h < 2.09439f) { + r = 65535.0f * i/3.0f *(1.0f + s * cos(h) / cosf(1.047196667f - h)); + g = 65535.0f * i/3.0f *(1.0f + s *(1.0f - cosf(h) / cos(1.047196667f - h))); + b = 65535.0f * i/3.0f *(1.0f - s); + } else if(h < 4.188787) { + h = h - 2.09439; + g = 65535.0f * i/3.0f *(1.0f + s * cosf(h) / cosf(1.047196667f - h)); + b = 65535.0f * i/3.0f *(1.0f + s * (1.0f - cosf(h) / cosf(1.047196667f - h))); + r = 65535.0f * i/3.0f *(1.0f - s); + } else { + h = h - 4.188787; + b = 65535.0f*i/3.0f * (1.0f + s * cosf(h) / cosf(1.047196667f - h)); + r = 65535.0f*i/3.0f * (1.0f + s * (1.0f - cosf(h) / cosf(1.047196667f - h))); + g = 65535.0f*i/3.0f * (1.0f - s); + } + *r_out = r > 65535 ? 65535 : r; + *g_out = g > 65535 ? 65535 : g; + *b_out = b > 65535 ? 65535 : b; +} + +void lcd_backlight_color(uint8_t hue, uint8_t saturation, uint8_t intensity) { + uint16_t r, g, b; + float hue_f = 360.0f * (float)hue / 255.0f; + float saturation_f = (float)saturation / 255.0f; + float intensity_f = (float)intensity / 255.0f; + intensity_f *= (float)current_brightness / 255.0f; + hsi_to_rgb(hue_f, saturation_f, intensity_f, &r, &g, &b); + current_hue = hue; + current_saturation = saturation; + current_intensity = intensity; + lcd_backlight_hal_color(r, g, b); +} + +void lcd_backlight_brightness(uint8_t b) { + current_brightness = b; + lcd_backlight_color(current_hue, current_saturation, current_intensity); +} diff --git a/lcd_backlight.h b/lcd_backlight.h new file mode 100644 index 00000000..dd3e37a0 --- /dev/null +++ b/lcd_backlight.h @@ -0,0 +1,42 @@ +/* +The MIT License (MIT) + +Copyright (c) 2016 Fred Sundvik + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. +*/ + +#ifndef LCD_BACKLIGHT_H_ +#define LCD_BACKLIGHT_H_ +#include "stdint.h" + +// Helper macros for storing hue, staturation and intensity as unsigned integers +#define LCD_COLOR(hue, saturation, intensity) (hue << 16 | saturation << 8 | intensity) +#define LCD_HUE(color) ((color >> 16) & 0xFF) +#define LCD_SAT(color) ((color >> 8) & 0xFF) +#define LCD_INT(color) (color & 0xFF) + +void lcd_backlight_init(void); +void lcd_backlight_color(uint8_t hue, uint8_t saturation, uint8_t intensity); +void lcd_backlight_brightness(uint8_t b); + +void lcd_backlight_hal_init(void); +void lcd_backlight_hal_color(uint16_t r, uint16_t g, uint16_t b); + +#endif /* LCD_BACKLIGHT_H_ */ diff --git a/visualizer.mk b/visualizer.mk index c5ae0dfa..8ffc1e4a 100644 --- a/visualizer.mk +++ b/visualizer.mk @@ -21,6 +21,13 @@ # SOFTWARE. GFXLIB = $(VISUALIZER_DIR)/ugfx +ifdef LCD_ENABLE include $(GFXLIB)/gfx.mk +endif SRC += $(GFXSRC) -INC += $(GFXINC) +INC += $(GFXINC) $(VISUALIZER_DIR) + +ifdef LCD_BACKLIGHT_ENABLE +SRC += $(VISUALIZER_DIR)/lcd_backlight.c +SRC += lcd_backlight_hal.c +endif