acid-drop

- Hacking the planet from a LilyGo T-Deck using custom firmware
git clone git://git.acid.vegas/acid-drop.git
lv_draw_sw_gradient.h (3596B)
      1 /**
      2  * @file lv_draw_sw_gradient.h
      3  *
      4  */
      5 
      6 #ifndef LV_DRAW_SW_GRADIENT_H
      7 #define LV_DRAW_SW_GRADIENT_H
      8 
      9 #ifdef __cplusplus
     10 extern "C" {
     11 #endif
     12 
     13 /*********************
     14  *      INCLUDES
     15  *********************/
     16 #include "../../misc/lv_color.h"
     17 #include "../../misc/lv_style.h"
     18 #include "lv_draw_sw_dither.h"
     19 
     20 /*********************
     21  *      DEFINES
     22  *********************/
     23 #if LV_GRADIENT_MAX_STOPS < 2
     24 #error LVGL needs at least 2 stops for gradients. Please increase the LV_GRADIENT_MAX_STOPS
     25 #endif
     26 
     27 
     28 /**********************
     29  *      TYPEDEFS
     30  **********************/
     31 #if _DITHER_GRADIENT
     32 typedef lv_color32_t lv_grad_color_t;
     33 #else
     34 typedef lv_color_t lv_grad_color_t;
     35 #endif
     36 
     37 /** To avoid recomputing gradient for each draw operation,
     38  *  it's possible to cache the computation in this structure instance.
     39  *  Whenever possible, this structure is reused instead of recomputing the gradient map */
     40 typedef struct _lv_gradient_cache_t {
     41     uint32_t        key;          /**< A discriminating key that's built from the drawing operation.
     42                                    * If the key does not match, the cache item is not used */
     43     uint32_t        life : 30;    /**< A life counter that's incremented on usage. Higher counter is
     44                                    * less likely to be evicted from the cache */
     45     uint32_t        filled : 1;   /**< Used to skip dithering in it if already done */
     46     uint32_t        not_cached: 1; /**< The cache was too small so this item is not managed by the cache*/
     47     lv_color_t   *  map;          /**< The computed gradient low bitdepth color map, points into the
     48                                    * cache's buffer, no free needed */
     49     lv_coord_t      alloc_size;   /**< The map allocated size in colors */
     50     lv_coord_t      size;         /**< The computed gradient color map size, in colors */
     51 #if _DITHER_GRADIENT
     52     lv_color32_t  * hmap;         /**< If dithering, we need to store the current, high bitdepth gradient
     53                                    * map too, points to the cache's buffer, no free needed */
     54 #if LV_DITHER_ERROR_DIFFUSION == 1
     55     lv_scolor24_t * error_acc;    /**< Error diffusion dithering algorithm requires storing the last error
     56                                    * drawn, points to the cache's buffer, no free needed  */
     57     lv_coord_t      w;            /**< The error array width in pixels */
     58 #endif
     59 #endif
     60 } lv_grad_t;
     61 
     62 
     63 /**********************
     64  *      PROTOTYPES
     65  **********************/
     66 /** Compute the color in the given gradient and fraction
     67  *  Gradient are specified in a virtual [0-255] range, so this function scales the virtual range to the given range
     68  * @param dsc       The gradient descriptor to use
     69  * @param range     The range to use in computation.
     70  * @param frac      The current part used in the range. frac is in [0; range]
     71  */
     72 LV_ATTRIBUTE_FAST_MEM lv_grad_color_t lv_gradient_calculate(const lv_grad_dsc_t * dsc, lv_coord_t range,
     73                                                             lv_coord_t frac);
     74 
     75 /**
     76  * Set the gradient cache size
     77  * @param max_bytes Max cahce size
     78  */
     79 void lv_gradient_set_cache_size(size_t max_bytes);
     80 
     81 /** Free the gradient cache */
     82 void lv_gradient_free_cache(void);
     83 
     84 /** Get a gradient cache from the given parameters */
     85 lv_grad_t * lv_gradient_get(const lv_grad_dsc_t * gradient, lv_coord_t w, lv_coord_t h);
     86 
     87 /**
     88  * Clean up the gradient item after it was get with `lv_grad_get_from_cache`.
     89  * @param grad      pointer to a gradient
     90  */
     91 void lv_gradient_cleanup(lv_grad_t * grad);
     92 
     93 #ifdef __cplusplus
     94 } /*extern "C"*/
     95 #endif
     96 
     97 #endif /*LV_DRAW_GRADIENT_H*/