label hint: comments and formatting

src/lv_draw/lv_draw_label.c

@@ -13,6 +13,7 @@
  *      DEFINES
  *********************/
 #define LABEL_RECOLOR_PAR_LENGTH 6
+#define LV_LABEL_HINT_UPDATE_TH		1024	/*Update the "hint" if the label's y coordinates have changed more then this*/
 
 /**********************
  *      TYPEDEFS
@@ -87,12 +88,17 @@ void lv_draw_label(const lv_area_t * coords, const lv_area_t * mask, const lv_st
 
     uint32_t line_start = 0;
     int32_t last_line_start = -1;
-    if(hint) {
-        if(LV_MATH_ABS(hint->coord_y - coords->y1) > 50) {
+
+    /*Check the hint to use the cached info*/
+    if(hint && y_ofs == 0) {
+    	/*If the label changed too much recalculate the hint.*/
+        if(LV_MATH_ABS(hint->coord_y - coords->y1) > LV_LABEL_HINT_UPDATE_TH - 2 * line_height) {
             hint->line_start = -1;
         }
         last_line_start = hint->line_start;
     }
+
+    /*Use the hint if it's valid*/
     if(last_line_start >= 0) {
         line_start = last_line_start;
         pos.y += hint->y;
@@ -107,12 +113,11 @@ void lv_draw_label(const lv_area_t * coords, const lv_area_t * mask, const lv_st
         line_end += lv_txt_get_next_line(&txt[line_start], font, style->text.letter_space, w, flag);
         pos.y += line_height;
 
-//        if(pos.y + line_height <= 0 && pos.y + 2 * line_height > 0 && hint_saved == false) {
-        if(pos.y  >= -100 && hint->line_start < 0) {
+        /*Save at the threshold coordinate*/
+        if(pos.y  >= -LV_LABEL_HINT_UPDATE_TH && hint->line_start < 0) {
             hint->line_start = line_start;
             hint->y = pos.y - coords->y1;
             hint->coord_y = coords->y1;
-            printf("in : %d, %d, %d\n", hint->line_start, hint->y, hint->coord_y);
         }
 
         if(txt[line_start] == '\0') return;

src/lv_draw/lv_draw_label.h

@@ -22,10 +22,21 @@ extern "C" {
 /**********************
  *      TYPEDEFS
  **********************/
-typedef struct
-{
+
+/* Store some info to speed up drawing of very large texts
+ * It takes a lot of time to get the first visible character because
+ * all the previous characters needs to be checked to calculate the positions.
+ * This structure stores an earlier (e.g. at -1000 px) coordinate and the index of that line.
+ * Therefore the calculations can start from here.*/
+typedef struct {
+	/*Index of the line at `y` coordinate*/
     int32_t line_start;
+
+    /*Give the `y` coordinate of the first letter at `line start` index. Relative to the label's coordinates*/
     int32_t y;
+
+    /*The 'y1' coordinate of the label when the hint was saved.
+     * Used to invalidate the hint if the label has moved too much. */
     int32_t coord_y;
 }lv_draw_label_hint_t;
 

src/lv_objx/lv_label.c

@@ -11,7 +11,6 @@
 
 #include "../lv_core/lv_obj.h"
 #include "../lv_core/lv_group.h"
-#include "../lv_draw/lv_draw.h"
 #include "../lv_misc/lv_color.h"
 #include "../lv_misc/lv_math.h"
 
@@ -24,6 +23,7 @@
 #endif
 
 #define LV_LABEL_DOT_END_INV 0xFFFF
+#define LV_LABEL_HINT_HEIGHT_LIMIT	1024		/*Enable "hint" to buffer info about labels larger than this. (Speed up their drawing)*/
 
 /**********************
  *      TYPEDEFS
@@ -50,7 +50,6 @@ static void lv_label_dot_tmp_free(lv_obj_t * label);
  *  STATIC VARIABLES
  **********************/
 static lv_signal_cb_t ancestor_signal;
-lv_draw_label_hint_t hint = {.line_start = -1};
 
 /**********************
  *      MACROS
@@ -96,6 +95,11 @@ lv_obj_t * lv_label_create(lv_obj_t * par, const lv_obj_t * copy)
 #endif
     ext->offset.x = 0;
     ext->offset.y = 0;
+
+    ext->hint.line_start = -1;
+    ext->hint.coord_y = 0;
+    ext->hint.y = 0;
+
 #if LV_LABEL_TEXT_SEL
     ext->txt_sel_start = LV_LABEL_TEXT_SEL_OFF;
     ext->txt_sel_end   = LV_LABEL_TEXT_SEL_OFF;
@@ -845,8 +849,11 @@ static bool lv_label_design(lv_obj_t * label, const lv_area_t * mask, lv_design_
             }
         }
 
+        lv_draw_label_hint_t * hint = &ext->hint;
+        if(ext->long_mode == LV_LABEL_LONG_ROLL_CIRC || lv_obj_get_height(label) < LV_LABEL_HINT_HEIGHT_LIMIT) hint = NULL;
+
         lv_draw_label(&coords, mask, style, opa_scale, ext->text, flag, &ext->offset,
-                      lv_label_get_text_sel_start(label), lv_label_get_text_sel_end(label), &hint);
+                      lv_label_get_text_sel_start(label), lv_label_get_text_sel_end(label), hint);
 
         if(ext->long_mode == LV_LABEL_LONG_ROLL_CIRC) {
             lv_point_t size;
@@ -941,6 +948,8 @@ static void lv_label_refr_text(lv_obj_t * label)
 
     if(ext->text == NULL) return;
 
+    ext->hint.line_start = -1;	/*The hint is invalid if the text changes*/
+
     lv_coord_t max_w         = lv_obj_get_width(label);
     const lv_style_t * style = lv_obj_get_style(label);
     const lv_font_t * font   = style->text.font;

src/lv_objx/lv_label.h

@@ -25,6 +25,7 @@ extern "C" {
 #include "../lv_font/lv_font.h"
 #include "../lv_font/lv_symbol_def.h"
 #include "../lv_misc/lv_txt.h"
+#include "../lv_draw/lv_draw.h"
 
 /*********************
  *      DEFINES
@@ -72,6 +73,7 @@ typedef struct
     uint16_t dot_end;  /*The text end position in dot mode (Handled by the library)*/
     lv_point_t offset; /*Text draw position offset*/
 
+    lv_draw_label_hint_t hint;	/*Used to buffer info about large text*/
 #if LV_USE_ANIMATION
     uint16_t anim_speed; /*Speed of scroll and roll animation in px/sec unit*/
 #endif

src/lv_objx/lv_ta.c

@@ -107,6 +107,7 @@ lv_obj_t * lv_ta_create(lv_obj_t * par, const lv_obj_t * copy)
     ext->cursor.style      = NULL;
     ext->cursor.blink_time = LV_TA_DEF_CURSOR_BLINK_TIME;
     ext->cursor.pos        = 0;
+    ext->cursor.click_pos  = 1;
     ext->cursor.type       = LV_CURSOR_LINE;
     ext->cursor.valid_x    = 0;
     ext->one_line          = 0;
@@ -617,6 +618,17 @@ void lv_ta_set_cursor_type(lv_obj_t * ta, lv_cursor_type_t cur_type)
     refr_cursor_area(ta);
 }
 
+/**
+ * Enable/Disable the positioning of the the cursor by clicking the text on the text area.
+ * @param ta pointer to a text area object
+ * @param en true: enable click positions; false: disable
+ */
+void lv_ta_set_cursor_click_pos(lv_obj_t * ta, bool en)
+{
+    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);
+    ext->cursor.click_pos = en ? 1 : 0;
+}
+
 /**
  * Enable/Disable password mode
  * @param ta pointer to a text area object
@@ -941,6 +953,17 @@ lv_cursor_type_t lv_ta_get_cursor_type(const lv_obj_t * ta)
     return ext->cursor.type;
 }
 
+/**
+ * Get whether the cursor click positioning is enabled or not.
+ * @param ta pointer to a text area object
+ * @return true: enable click positions; false: disable
+ */
+bool lv_ta_get_cursor_click_pos(lv_obj_t * ta)
+{
+    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);
+    return ext->cursor.click_pos ? true : false;
+}
+
 /**
  * Get the password mode attribute
  * @param ta pointer to a text area object
@@ -1586,6 +1609,8 @@ static void get_cursor_style(lv_obj_t * ta, lv_style_t * style_res)
 static void refr_cursor_area(lv_obj_t * ta)
 {
     lv_ta_ext_t * ext              = lv_obj_get_ext_attr(ta);
+
+
     const lv_style_t * label_style = lv_obj_get_style(ext->label);
 
     lv_style_t cur_style;
@@ -1707,14 +1732,18 @@ static void placeholder_update(lv_obj_t * ta)
 
 static void update_cursor_position_on_click(lv_obj_t * ta, lv_signal_t sign, lv_indev_t * click_source)
 {
+
     if(click_source == NULL) return;
 
+    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);
+    if(ext->cursor.click_pos == 0) return;
+	if(ext->cursor.type == LV_CURSOR_NONE) return;
+
     if(lv_indev_get_type(click_source) == LV_INDEV_TYPE_KEYPAD ||
        lv_indev_get_type(click_source) == LV_INDEV_TYPE_ENCODER) {
         return;
     }
 
-    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);
 
     lv_area_t label_coords;
     lv_obj_get_coords(ext->label, &label_coords);

src/lv_objx/lv_ta.h

@@ -76,6 +76,7 @@ typedef struct
         uint16_t txt_byte_pos;     /* Byte index of the letter after (on) the cursor*/
         lv_cursor_type_t type : 4; /* Shape of the cursor*/
         uint8_t state : 1;         /*Cursor is visible now or not (Handled by the library)*/
+        uint8_t click_pos	:1;	   /*1: Enable positioning the cursor by clicking the text area*/
     } cursor;
 #if LV_LABEL_TEXT_SEL
     uint16_t tmp_sel_start;       /*Temporary value*/
@@ -173,6 +174,13 @@ void lv_ta_set_cursor_pos(lv_obj_t * ta, int16_t pos);
  */
 void lv_ta_set_cursor_type(lv_obj_t * ta, lv_cursor_type_t cur_type);
 
+/**
+ * Enable/Disable the positioning of the the cursor by clicking the text on the text area.
+ * @param ta pointer to a text area object
+ * @param en true: enable click positions; false: disable
+ */
+void lv_ta_set_cursor_click_pos(lv_obj_t * ta, bool en);
+
 /**
  * Enable/Disable password mode
  * @param ta pointer to a text area object
@@ -319,6 +327,13 @@ uint16_t lv_ta_get_cursor_pos(const lv_obj_t * ta);
  */
 lv_cursor_type_t lv_ta_get_cursor_type(const lv_obj_t * ta);
 
+/**
+ * Get whether the cursor click positioning is enabled or not.
+ * @param ta pointer to a text area object
+ * @return true: enable click positions; false: disable
+ */
+bool lv_ta_get_cursor_click_pos(lv_obj_t * ta);
+
 /**
  * Get the password mode attribute
  * @param ta pointer to a text area object