1 /**
2  * @file lv_qrcode.c
3  *
4  */
5 
6 /*********************
7  *      INCLUDES
8  *********************/
9 #include "lv_qrcode.h"
10 #if LV_USE_QRCODE
11 
12 #include "qrcodegen.h"
13 
14 /*********************
15  *      DEFINES
16  *********************/
17 #define MY_CLASS &lv_qrcode_class
18 
19 /**********************
20  *      TYPEDEFS
21  **********************/
22 
23 /**********************
24  *  STATIC PROTOTYPES
25  **********************/
26 static void lv_qrcode_constructor(const lv_obj_class_t * class_p, lv_obj_t * obj);
27 static void lv_qrcode_destructor(const lv_obj_class_t * class_p, lv_obj_t * obj);
28 
29 /**********************
30  *  STATIC VARIABLES
31  **********************/
32 
33 const lv_obj_class_t lv_qrcode_class = {
34     .constructor_cb = lv_qrcode_constructor,
35     .destructor_cb = lv_qrcode_destructor,
36     .base_class = &lv_canvas_class
37 };
38 
39 static lv_coord_t size_param;
40 static lv_color_t dark_color_param;
41 static lv_color_t light_color_param;
42 
43 /**********************
44  *      MACROS
45  **********************/
46 
47 /**********************
48  *   GLOBAL FUNCTIONS
49  **********************/
50 
51 /**
52  * Create an empty QR code (an `lv_canvas`) object.
53  * @param parent point to an object where to create the QR code
54  * @param size width and height of the QR code
55  * @param dark_color dark color of the QR code
56  * @param light_color light color of the QR code
57  * @return pointer to the created QR code object
58  */
lv_qrcode_create(lv_obj_t * parent,lv_coord_t size,lv_color_t dark_color,lv_color_t light_color)59 lv_obj_t * lv_qrcode_create(lv_obj_t * parent, lv_coord_t size, lv_color_t dark_color, lv_color_t light_color)
60 {
61     LV_LOG_INFO("begin");
62     size_param = size;
63     light_color_param = light_color;
64     dark_color_param = dark_color;
65 
66     lv_obj_t * obj = lv_obj_class_create_obj(MY_CLASS, parent);
67     lv_obj_class_init_obj(obj);
68     return obj;
69 
70 }
71 
72 /**
73  * Set the data of a QR code object
74  * @param qrcode pointer to aQ code object
75  * @param data data to display
76  * @param data_len length of data in bytes
77  * @return LV_RES_OK: if no error; LV_RES_INV: on error
78  */
lv_qrcode_update(lv_obj_t * qrcode,const void * data,uint32_t data_len)79 lv_res_t lv_qrcode_update(lv_obj_t * qrcode, const void * data, uint32_t data_len)
80 {
81     lv_color_t c;
82     c.full = 1;
83     lv_canvas_fill_bg(qrcode, c, LV_OPA_COVER);
84 
85     if(data_len > qrcodegen_BUFFER_LEN_MAX) return LV_RES_INV;
86 
87     lv_img_dsc_t * imgdsc = lv_canvas_get_img(qrcode);
88 
89     int32_t qr_version = qrcodegen_getMinFitVersion(qrcodegen_Ecc_MEDIUM, data_len);
90     if(qr_version <= 0) return LV_RES_INV;
91     int32_t qr_size = qrcodegen_version2size(qr_version);
92     if(qr_size <= 0) return LV_RES_INV;
93     int32_t scale = imgdsc->header.w / qr_size;
94     if(scale <= 0) return LV_RES_INV;
95     int32_t remain = imgdsc->header.w % qr_size;
96 
97     /* The qr version is incremented by four point */
98     uint32_t version_extend = remain / (scale << 2);
99     if(version_extend && qr_version < qrcodegen_VERSION_MAX) {
100         qr_version = qr_version + version_extend > qrcodegen_VERSION_MAX ?
101                      qrcodegen_VERSION_MAX : qr_version + version_extend;
102     }
103 
104     uint8_t * qr0 = lv_mem_alloc(qrcodegen_BUFFER_LEN_FOR_VERSION(qr_version));
105     LV_ASSERT_MALLOC(qr0);
106     uint8_t * data_tmp = lv_mem_alloc(qrcodegen_BUFFER_LEN_FOR_VERSION(qr_version));
107     LV_ASSERT_MALLOC(data_tmp);
108     lv_memcpy(data_tmp, data, data_len);
109 
110     bool ok = qrcodegen_encodeBinary(data_tmp, data_len,
111                                      qr0, qrcodegen_Ecc_MEDIUM,
112                                      qr_version, qr_version,
113                                      qrcodegen_Mask_AUTO, true);
114 
115     if(!ok) {
116         lv_mem_free(qr0);
117         lv_mem_free(data_tmp);
118         return LV_RES_INV;
119     }
120 
121     lv_coord_t obj_w = imgdsc->header.w;
122     qr_size = qrcodegen_getSize(qr0);
123     scale = obj_w / qr_size;
124     int scaled = qr_size * scale;
125     int margin = (obj_w - scaled) / 2;
126     uint8_t * buf_u8 = (uint8_t *)imgdsc->data + 8;    /*+8 skip the palette*/
127 
128     /* Copy the qr code canvas:
129      * A simple `lv_canvas_set_px` would work but it's slow for so many pixels.
130      * So buffer 1 byte (8 px) from the qr code and set it in the canvas image */
131     uint32_t row_byte_cnt = (imgdsc->header.w + 7) >> 3;
132     int y;
133     for(y = margin; y < scaled + margin; y += scale) {
134         uint8_t b = 0;
135         uint8_t p = 0;
136         bool aligned = false;
137         int x;
138         for(x = margin; x < scaled + margin; x++) {
139             bool a = qrcodegen_getModule(qr0, (x - margin) / scale, (y - margin) / scale);
140 
141             if(aligned == false && (x & 0x7) == 0) aligned = true;
142 
143             if(aligned == false) {
144                 c.full = a ? 0 : 1;
145                 lv_canvas_set_px_color(qrcode, x, y, c);
146             }
147             else {
148                 if(!a) b |= (1 << (7 - p));
149                 p++;
150                 if(p == 8) {
151                     uint32_t px = row_byte_cnt * y + (x >> 3);
152                     buf_u8[px] = b;
153                     b = 0;
154                     p = 0;
155                 }
156             }
157         }
158 
159         /*Process the last byte of the row*/
160         if(p) {
161             /*Make the rest of the bits white*/
162             b |= (1 << (8 - p)) - 1;
163 
164             uint32_t px = row_byte_cnt * y + (x >> 3);
165             buf_u8[px] = b;
166         }
167 
168         /*The Qr is probably scaled so simply to the repeated rows*/
169         int s;
170         const uint8_t * row_ori = buf_u8 + row_byte_cnt * y;
171         for(s = 1; s < scale; s++) {
172             lv_memcpy((uint8_t *)buf_u8 + row_byte_cnt * (y + s), row_ori, row_byte_cnt);
173         }
174     }
175 
176     lv_mem_free(qr0);
177     lv_mem_free(data_tmp);
178     return LV_RES_OK;
179 }
180 
181 
lv_qrcode_delete(lv_obj_t * qrcode)182 void lv_qrcode_delete(lv_obj_t * qrcode)
183 {
184     lv_obj_del(qrcode);
185 }
186 
187 /**********************
188  *   STATIC FUNCTIONS
189  **********************/
190 
lv_qrcode_constructor(const lv_obj_class_t * class_p,lv_obj_t * obj)191 static void lv_qrcode_constructor(const lv_obj_class_t * class_p, lv_obj_t * obj)
192 {
193     LV_UNUSED(class_p);
194 
195     uint32_t buf_size = LV_CANVAS_BUF_SIZE_INDEXED_1BIT(size_param, size_param);
196     uint8_t * buf = lv_mem_alloc(buf_size);
197     LV_ASSERT_MALLOC(buf);
198     if(buf == NULL) return;
199 
200     lv_canvas_set_buffer(obj, buf, size_param, size_param, LV_IMG_CF_INDEXED_1BIT);
201     lv_canvas_set_palette(obj, 0, dark_color_param);
202     lv_canvas_set_palette(obj, 1, light_color_param);
203 }
204 
lv_qrcode_destructor(const lv_obj_class_t * class_p,lv_obj_t * obj)205 static void lv_qrcode_destructor(const lv_obj_class_t * class_p, lv_obj_t * obj)
206 {
207     LV_UNUSED(class_p);
208 
209     lv_img_dsc_t * img = lv_canvas_get_img(obj);
210     lv_img_cache_invalidate_src(img);
211     lv_mem_free((void *)img->data);
212     img->data = NULL;
213 }
214 
215 #endif /*LV_USE_QRCODE*/
216