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 19 #if LV_USE_DRAW_SW 20 21 /********************* 22 * DEFINES 23 *********************/ 24 #if LV_GRADIENT_MAX_STOPS < 2 25 #error LVGL needs at least 2 stops for gradients. Please increase the LV_GRADIENT_MAX_STOPS 26 #endif 27 28 #define LV_GRAD_LEFT LV_PCT(0) 29 #define LV_GRAD_RIGHT LV_PCT(100) 30 #define LV_GRAD_TOP LV_PCT(0) 31 #define LV_GRAD_BOTTOM LV_PCT(100) 32 #define LV_GRAD_CENTER LV_PCT(50) 33 34 /********************** 35 * TYPEDEFS 36 **********************/ 37 typedef lv_color_t lv_grad_color_t; 38 39 /********************** 40 * PROTOTYPES 41 **********************/ 42 /** Compute the color in the given gradient and fraction 43 * Gradient are specified in a virtual [0-255] range, so this function scales the virtual range to the given range 44 * @param dsc The gradient descriptor to use 45 * @param range The range to use in computation. 46 * @param frac The current part used in the range. frac is in [0; range] 47 * @param color_out Calculated gradient color 48 * @param opa_out Calculated opacity 49 */ 50 51 void /* LV_ATTRIBUTE_FAST_MEM */ lv_gradient_color_calculate(const lv_grad_dsc_t * dsc, int32_t range, 52 int32_t frac, lv_grad_color_t * color_out, lv_opa_t * opa_out); 53 54 /** Get a gradient cache from the given parameters */ 55 lv_grad_t * lv_gradient_get(const lv_grad_dsc_t * gradient, int32_t w, int32_t h); 56 57 /** 58 * Clean up the gradient item after it was get with `lv_grad_get_from_cache`. 59 * @param grad pointer to a gradient 60 */ 61 void lv_gradient_cleanup(lv_grad_t * grad); 62 63 /** 64 * Initialize gradient color map from a table 65 * @param grad pointer to a gradient descriptor 66 * @param colors color array 67 * @param fracs position array (0..255): if NULL, then colors are distributed evenly 68 * @param opa opacity array: if NULL, then LV_OPA_COVER is assumed 69 * @param num_stops number of gradient stops (1..LV_GRADIENT_MAX_STOPS) 70 */ 71 void lv_gradient_init_stops(lv_grad_dsc_t * grad, const lv_color_t colors[], const lv_opa_t opa[], 72 const uint8_t fracs[], int num_stops); 73 74 #if LV_USE_DRAW_SW_COMPLEX_GRADIENTS 75 76 /** 77 * Helper function to initialize linear gradient 78 * @param dsc gradient descriptor 79 * @param from_x start x position: can be a coordinate or an lv_pct() value 80 * predefined constants LV_GRAD_LEFT, LV_GRAD_RIGHT, LV_GRAD_TOP, LV_GRAD_BOTTOM, LV_GRAD_CENTER can be used as well 81 * @param from_y start y position 82 * @param to_x end x position 83 * @param to_y end y position 84 * @param extend one of LV_GRAD_EXTEND_PAD, LV_GRAD_EXTEND_REPEAT or LV_GRAD_EXTEND_REFLECT 85 */ 86 void lv_grad_linear_init(lv_grad_dsc_t * dsc, int32_t from_x, int32_t from_y, int32_t to_x, int32_t to_y, 87 lv_grad_extend_t extend); 88 89 /** 90 * Helper function to initialize radial gradient 91 * @param dsc gradient descriptor 92 * @param center_x center x position: can be a coordinate or an lv_pct() value 93 * predefined constants LV_GRAD_LEFT, LV_GRAD_RIGHT, LV_GRAD_TOP, LV_GRAD_BOTTOM, LV_GRAD_CENTER can be used as well 94 * @param center_y center y position 95 * @param to_x point on the end circle x position 96 * @param to_y point on the end circle y position 97 * @param extend one of LV_GRAD_EXTEND_PAD, LV_GRAD_EXTEND_REPEAT or LV_GRAD_EXTEND_REFLECT 98 */ 99 void lv_grad_radial_init(lv_grad_dsc_t * dsc, int32_t center_x, int32_t center_y, int32_t to_x, int32_t to_y, 100 lv_grad_extend_t extend); 101 102 /** 103 * Set focal (starting) circle of a radial gradient 104 * @param dsc gradient descriptor 105 * @param center_x center x position: can be a coordinate or an lv_pct() value 106 * predefined constants LV_GRAD_LEFT, LV_GRAD_RIGHT, LV_GRAD_TOP, LV_GRAD_BOTTOM, LV_GRAD_CENTER can be used as well 107 * @param center_y center y position 108 * @param radius radius of the starting circle (NOTE: this must be a scalar number, not percentage) 109 */ 110 void lv_grad_radial_set_focal(lv_grad_dsc_t * dsc, int32_t center_x, int32_t center_y, int32_t radius); 111 112 /** 113 * Helper function to initialize conical gradient 114 * @param dsc gradient descriptor 115 * @param center_x center x position: can be a coordinate or an lv_pct() value 116 * predefined constants LV_GRAD_LEFT, LV_GRAD_RIGHT, LV_GRAD_TOP, LV_GRAD_BOTTOM, LV_GRAD_CENTER can be used as well 117 * @param center_y center y position 118 * @param start_angle start angle in degrees 119 * @param end_angle end angle in degrees 120 * @param extend one of LV_GRAD_EXTEND_PAD, LV_GRAD_EXTEND_REPEAT or LV_GRAD_EXTEND_REFLECT 121 */ 122 void lv_grad_conical_init(lv_grad_dsc_t * dsc, int32_t center_x, int32_t center_y, int32_t start_angle, 123 int32_t end_angle, lv_grad_extend_t extend); 124 125 /** 126 * Calculate constants from the given parameters that are used during rendering 127 * @param dsc gradient descriptor 128 */ 129 void lv_gradient_linear_setup(lv_grad_dsc_t * dsc, const lv_area_t * coords); 130 131 /** 132 * Free up the allocated memory for the gradient calculation 133 * @param dsc gradient descriptor 134 */ 135 void lv_gradient_linear_cleanup(lv_grad_dsc_t * dsc); 136 137 /** 138 * Calculate a line segment of a linear gradient 139 * @param dsc gradient descriptor 140 * @param xp starting point x coordinate in gradient space 141 * @param yp starting point y coordinate in gradient space 142 * @param width width of the line segment in pixels 143 * @param result color buffer for the resulting line segment 144 */ 145 void /* LV_ATTRIBUTE_FAST_MEM */ lv_gradient_linear_get_line(lv_grad_dsc_t * dsc, int32_t xp, int32_t yp, int32_t width, 146 lv_grad_t * result); 147 148 /** 149 * Calculate constants from the given parameters that are used during rendering 150 * @param dsc gradient descriptor 151 */ 152 void lv_gradient_radial_setup(lv_grad_dsc_t * dsc, const lv_area_t * coords); 153 154 /** 155 * Free up the allocated memory for the gradient calculation 156 * @param dsc gradient descriptor 157 */ 158 void lv_gradient_radial_cleanup(lv_grad_dsc_t * dsc); 159 160 /** 161 * Calculate a line segment of a radial gradient 162 * @param dsc gradient descriptor 163 * @param xp starting point x coordinate in gradient space 164 * @param yp starting point y coordinate in gradient space 165 * @param width width of the line segment in pixels 166 * @param result color buffer for the resulting line segment 167 */ 168 void /* LV_ATTRIBUTE_FAST_MEM */ lv_gradient_radial_get_line(lv_grad_dsc_t * dsc, int32_t xp, int32_t yp, int32_t width, 169 lv_grad_t * result); 170 171 /** 172 * Calculate constants from the given parameters that are used during rendering 173 * @param dsc gradient descriptor 174 */ 175 void lv_gradient_conical_setup(lv_grad_dsc_t * dsc, const lv_area_t * coords); 176 177 /** 178 * Free up the allocated memory for the gradient calculation 179 * @param dsc gradient descriptor 180 */ 181 void lv_gradient_conical_cleanup(lv_grad_dsc_t * dsc); 182 183 /** 184 * Calculate a line segment of a conical gradient 185 * @param dsc gradient descriptor 186 * @param xp starting point x coordinate in gradient space 187 * @param yp starting point y coordinate in gradient space 188 * @param width width of the line segment in pixels 189 * @param result color buffer for the resulting line segment 190 */ 191 void /* LV_ATTRIBUTE_FAST_MEM */ lv_gradient_conical_get_line(lv_grad_dsc_t * dsc, int32_t xp, int32_t yp, 192 int32_t width, 193 lv_grad_t * result); 194 195 #endif /*LV_USE_DRAW_SW_COMPLEX_GRADIENTS*/ 196 197 #endif /*LV_USE_DRAW_SW*/ 198 199 #ifdef __cplusplus 200 } /*extern "C"*/ 201 #endif 202 203 #endif /*LV_DRAW_GRADIENT_H*/ 204
