feat(draw_buf): add option to select draw_buf implementation

lv_conf_template.h

@@ -86,12 +86,18 @@
 /*========================
  * RENDERING CONFIGURATION
  *========================*/
+/* Select a draw buffer implementation. Possible values:
+ * - LV_DRAW_BUF_BASIC:     LVGL's built in implementation
+ * - LV_DRAW_BUF_CUSTOM:    Implement teh function of lv_draw_buf.h externally
+ */
+#define LV_USE_DRAW_BUF    LV_DRAW_BUF_BASIC
 
-/*Align the stride of all layers and images to this bytes*/
+#if LV_USE_DRAW_BUF == LV_DRAW_BUF_BASIC
-#define LV_DRAW_BUF_STRIDE_ALIGN                1
+    /*Align the stride of all layers and images to this bytes*/
-
+    #define LV_DRAW_BUF_STRIDE_ALIGN                1          /*Multiple of these Bytes*/
-/*Align the start address of draw_buf addresses to this bytes*/
+    /*Align the start address of draw_buf addresses to this bytes*/
-#define LV_DRAW_BUF_ALIGN                       4
+    #define LV_DRAW_BUF_ALIGN                       4
+#endif
 
 /* Max. memory to be used for layers */
 #define  LV_LAYER_MAX_MEMORY_USAGE             150       /*[kB]*/

src/draw/draw_buf/lv_draw_buf.h

@@ -25,36 +25,106 @@ extern "C" {
  **********************/
 typedef struct {
     void * buf;
-
     lv_coord_t width;
     lv_coord_t height;
     lv_color_format_t color_format;
+    uint32_t usage_cnt;
+    uint32_t flags;
 } lv_draw_buf_t;
 
-void lv_draw_buf_init(lv_draw_buf_t * draw_buf, lv_coord_t w, lv_coord_t h, lv_color_format_t color_format);
-void lv_draw_buf_malloc(lv_draw_buf_t * draw_buf);
-void lv_draw_buf_realloc(lv_draw_buf_t  * buf, lv_coord_t w, lv_coord_t h, lv_color_format_t color_format);
-void lv_draw_buf_free(lv_draw_buf_t  * buf);
-void * lv_draw_buf_get_buf(lv_draw_buf_t * draw_buf);
-void lv_draw_buf_invalidate_cache(lv_draw_buf_t  * buf);
-
-uint32_t lv_draw_buf_get_stride(const lv_draw_buf_t * draw_buf);
-void * lv_draw_buf_go_to_xy(lv_draw_buf_t * draw_buf, lv_coord_t x, lv_coord_t y);
-void lv_draw_buf_clear(lv_draw_buf_t * draw_buf, const lv_area_t * a);
-
-void lv_draw_buf_copy(void * dest_buf, uint32_t dest_stride, const lv_area_t * dest_area,
-                      void * src_buf, uint32_t src_stride, const lv_area_t * src_area, lv_color_format_t color_format);
-
-static inline uint32_t lv_draw_buf_width_to_stride(uint32_t w, lv_color_format_t color_format)
-{
-    uint32_t width_byte =  w * lv_color_format_get_size(color_format);
-    return (width_byte + LV_DRAW_BUF_STRIDE_ALIGN - 1) & ~(LV_DRAW_BUF_STRIDE_ALIGN - 1);
-}
 
 /**********************
  * GLOBAL PROTOTYPES
  **********************/
 
+/**
+ * Initialize a draw buffer object. The buffer won't be allocated
+ * @param draw_buf          pointer to a draw buffer
+ * @param w                 the width of the buffer in pixel
+ * @param h                 the height of the buffer in pixel
+ * @param color_format      the color format of the buffer
+ */
+void lv_draw_buf_init(lv_draw_buf_t * draw_buf, lv_coord_t w, lv_coord_t h, lv_color_format_t color_format);
+
+/**
+ * Allocate a buffer in the draw_buf, considering the set width, height and color format
+ * @param draw_buf          pointer to a draw buffer
+ */
+void lv_draw_buf_malloc(lv_draw_buf_t * draw_buf);
+
+/**
+ * Realloacte the buffer with a new width, height and color format
+ * @param draw_buf          pointer to a draw buffer
+ * @param w                 the new width of the buffer in pixel
+ * @param h                 the new height of the buffer in pixel
+ * @param color_format      the new color format of the buffer
+ */
+void lv_draw_buf_realloc(lv_draw_buf_t  * draw_buf, lv_coord_t w, lv_coord_t h, lv_color_format_t color_format);
+
+/**
+ * Free the allocated buffer
+ * @param draw_buf          pointer to draw buffer
+ */
+void lv_draw_buf_free(lv_draw_buf_t  * draw_buf);
+
+/**
+ * Get the buffer of the draw_buf.
+ * Never get the buffer as draw_buf->buf adn this function might align the buffer
+ * @param draw_buf          pointer to a draw buffer
+ * @return                  pointer to the buffer
+ */
+void * lv_draw_buf_get_buf(lv_draw_buf_t * draw_buf);
+
+/**
+ * Invalidate the cache of the buffer
+ * @param draw_buf          pointer to a draw buffer
+ */
+void lv_draw_buf_invalidate_cache(lv_draw_buf_t  * draw_buf);
+
+
+/**
+ * Calculate the stride in bytes based on a width and color format
+ * @param w                 the width in pixels
+ * @param color_format      the color format
+ * @return                  the stride in bytes
+ */
+uint32_t lv_draw_buf_width_to_stride(uint32_t w, lv_color_format_t color_format);
+
+/**
+ * Get the stride of a draw buffer using the set width and color format
+ * @param draw_buf          pointer to draw buffer
+ * @return                  the stride in bytes
+ */
+uint32_t lv_draw_buf_get_stride(const lv_draw_buf_t * draw_buf);
+
+/**
+ * Go to the X, Y coordinate on the buffer.
+ * @param draw_buf          pointer to draw buffer
+ * @param x                 the X coordinate to seek
+ * @param y                 the Y coordinate to seek
+ */
+void * lv_draw_buf_go_to_xy(lv_draw_buf_t * draw_buf, lv_coord_t x, lv_coord_t y);
+
+/**
+ * Clear an area on the buffer
+ * @param draw_buf          pointer to draw buffer
+ * @param a                 the area to clear, or NULL to clear the whole buffer
+ */
+void lv_draw_buf_clear(lv_draw_buf_t * draw_buf, const lv_area_t * a);
+
+/**
+ * Copy an area from a buffer to an other
+ * @param dest_buf          pointer to the destination buffer (not draw_buf)
+ * @param dest_stride       the stride of the destination buffer in bytes
+ * @param dest_area         pointer to the destination area
+ * @param src_buf           pointer to the source buffer (not draw_buf)
+ * @param src_stride        the stride of the source buffer in bytes
+ * @param src_area          pointer to the source area
+ * @param color_format      the color format (should be the same for the source and destination)
+ */
+void lv_draw_buf_copy(void * dest_buf, uint32_t dest_stride, const lv_area_t * dest_area,
+                      void * src_buf, uint32_t src_stride, const lv_area_t * src_area, lv_color_format_t color_format);
+
 /**********************
  *      MACROS
  **********************/

src/draw/draw_buf/lv_draw_buf_basic.c

@@ -1,14 +1,18 @@
 /**
- * @file lv_draw_buf.c
+ * @file lv_draw_buf_basic.c
  *
  */
 
 /*********************
  *      INCLUDES
  *********************/
+#include "../../misc/lv_types.h"
 #include "lv_draw_buf.h"
+#if LV_USE_DRAW_BUF == LV_DRAW_BUF_BASIC
+
 #include "../../stdlib/lv_string.h"
 
+
 /*********************
  *      DEFINES
  *********************/
@@ -74,7 +78,12 @@ void * lv_draw_buf_get_buf(lv_draw_buf_t * draw_buf)
 void lv_draw_buf_invalidate_cache(lv_draw_buf_t  * draw_buf)
 {
     LV_UNUSED(draw_buf);
+}
 
+uint32_t lv_draw_buf_width_to_stride(uint32_t w, lv_color_format_t color_format)
+{
+    uint32_t width_byte =  w * lv_color_format_get_size(color_format);
+    return (width_byte + LV_DRAW_BUF_STRIDE_ALIGN - 1) & ~(LV_DRAW_BUF_STRIDE_ALIGN - 1);
 }
 
 uint32_t lv_draw_buf_get_stride(const lv_draw_buf_t * draw_buf)
@@ -93,9 +102,9 @@ void * lv_draw_buf_go_to_xy(lv_draw_buf_t * draw_buf, lv_coord_t x, lv_coord_t y
     return buf_tmp;
 }
 
-
 void lv_draw_buf_clear(lv_draw_buf_t * draw_buf, const lv_area_t * a)
 {
+    //TODO clear the area
     LV_UNUSED(a);
     uint32_t stride = lv_draw_buf_get_stride(draw_buf);
     uint8_t * buf = lv_draw_buf_get_buf(draw_buf);
@@ -139,3 +148,6 @@ static uint8_t * buf_alloc(void * old_buf, lv_coord_t w, lv_coord_t h)
 
     return buf;
 }
+
+
+#endif /*LV_USE DRAW_BUF == LV_DRAW_BUF_BASIC*/

src/lv_conf_internal.h

@@ -214,26 +214,38 @@
 /*========================
  * RENDERING CONFIGURATION
  *========================*/
-
+/* Select a draw buffer implementation. Possible values:
-/*Align the stride of all layers and images to this bytes*/
+ * - LV_DRAW_BUF_BASIC:     LVGL's built in implementation
-#ifndef LV_DRAW_BUF_STRIDE_ALIGN
+ * - LV_DRAW_BUF_CUSTOM:    Implement teh function of lv_draw_buf.h externally
-    #ifdef _LV_KCONFIG_PRESENT
+ */
-        #ifdef CONFIG_LV_DRAW_BUF_STRIDE_ALIGN
+#ifndef LV_USE_DRAW_BUF
-            #define LV_DRAW_BUF_STRIDE_ALIGN CONFIG_LV_DRAW_BUF_STRIDE_ALIGN
+    #ifdef CONFIG_LV_USE_DRAW_BUF
-        #else
+        #define LV_USE_DRAW_BUF CONFIG_LV_USE_DRAW_BUF
-            #define LV_DRAW_BUF_STRIDE_ALIGN 0
-        #endif
     #else
-        #define LV_DRAW_BUF_STRIDE_ALIGN                1
+        #define LV_USE_DRAW_BUF    LV_DRAW_BUF_BASIC
     #endif
 #endif
 
-/*Align the start address of draw_buf addresses to this bytes*/
+#if LV_USE_DRAW_BUF == LV_DRAW_BUF_BASIC
-#ifndef LV_DRAW_BUF_ALIGN
+    /*Align the stride of all layers and images to this bytes*/
-    #ifdef CONFIG_LV_DRAW_BUF_ALIGN
+    #ifndef LV_DRAW_BUF_STRIDE_ALIGN
-        #define LV_DRAW_BUF_ALIGN CONFIG_LV_DRAW_BUF_ALIGN
+        #ifdef _LV_KCONFIG_PRESENT
-    #else
+            #ifdef CONFIG_LV_DRAW_BUF_STRIDE_ALIGN
-        #define LV_DRAW_BUF_ALIGN                       4
+                #define LV_DRAW_BUF_STRIDE_ALIGN CONFIG_LV_DRAW_BUF_STRIDE_ALIGN
+            #else
+                #define LV_DRAW_BUF_STRIDE_ALIGN 0
+            #endif
+        #else
+            #define LV_DRAW_BUF_STRIDE_ALIGN                1          /*Multiple of these Bytes*/
+        #endif
+    #endif
+    /*Align the start address of draw_buf addresses to this bytes*/
+    #ifndef LV_DRAW_BUF_ALIGN
+        #ifdef CONFIG_LV_DRAW_BUF_ALIGN
+            #define LV_DRAW_BUF_ALIGN CONFIG_LV_DRAW_BUF_ALIGN
+        #else
+            #define LV_DRAW_BUF_ALIGN                       4
+        #endif
     #endif
 #endif
 

src/misc/lv_types.h

@@ -44,6 +44,9 @@ extern "C" {
 #define LV_STDLIB_MICROPYTHON       2
 #define LV_STDLIB_CUSTOM            255
 
+#define LV_DRAW_BUF_BASIC           0
+#define LV_DRAW_BUF_CUSTOM          255
+
 /**********************
  *      TYPEDEFS
  **********************/