Add gfx_getFontHeigth() function

openrtx/include/interfaces/graphics.h

@@ -223,6 +223,26 @@ void gfx_drawRect(point_t start, uint16_t width, uint16_t height, color_t color,
  */
 void gfx_drawCircle(point_t start, uint16_t r, color_t color);
 
+/**
+ * Estimates the maximum font height by reading the gliph | height
+ * @param size: text font size, defined as enum.
+ * @return font height
+ */
+uint8_t gfx_getFontHeight(fontSize_t size);
+
+/**
+ * Prints text on the screen at the specified coordinates.
+ * Reads text from a given char buffer
+ * @param start: text line start point, in pixel coordinates.
+ * @param size: text font size, defined as enum.
+ * @param alignment: text alignment type, defined as enum.
+ * @param color: text color, in color_t format.
+ * @param buf: char buffer
+ * @return text width and height as point_t coordinates
+ */
+point_t gfx_printBuffer(point_t start, fontSize_t size, textAlign_t alignment, 
+                        color_t color, const char *buf);
+
 /**
  * Prints text on the screen at the specified coordinates.
  * @param start: text line start point, in pixel coordinates.
@@ -232,7 +252,8 @@ void gfx_drawCircle(point_t start, uint16_t r, color_t color);
  * @param fmt: printf style format string
  * @return text width and height as point_t coordinates
  */
-point_t gfx_print(point_t start, fontSize_t size, textAlign_t alignment, color_t color, const char* fmt, ... );
+point_t gfx_print(point_t start, fontSize_t size, textAlign_t alignment, 
+                  color_t color, const char* fmt, ... );
 
 /**
  * Prints text on the screen, calculating the print position.
@@ -248,8 +269,9 @@ point_t gfx_print(point_t start, fontSize_t size, textAlign_t alignment, color_t
  * @param fmt: printf style format string
  * @return text width and height as point_t coordinates
  */
-point_t gfx_printLine(uint8_t cur, uint8_t tot, uint16_t startY, uint16_t endY, uint16_t startX, 
-                      fontSize_t size, textAlign_t alignment, color_t color, const char* fmt, ... );
+point_t gfx_printLine(uint8_t cur, uint8_t tot, uint16_t startY, uint16_t endY, 
+                      uint16_t startX, fontSize_t size, textAlign_t alignment, 
+                      color_t color, const char* fmt, ... );
 
 /**
  * Prints an error message surrounded by a red box on the screen.

openrtx/src/graphics.c

@@ -385,6 +385,13 @@ static inline uint16_t get_reset_x(textAlign_t alignment, uint16_t line_size,
     return 0;
 }
 
+uint8_t gfx_getFontHeight(fontSize_t size)
+{
+    GFXfont f = fonts[size];
+    GFXglyph glyph = f.glyph['|' - f.first];
+    return glyph.height;
+}
+
 point_t gfx_printBuffer(point_t start, fontSize_t size, textAlign_t alignment, 
                         color_t color, const char *buf)
 {
@@ -503,6 +510,13 @@ point_t gfx_printLine(uint8_t cur, uint8_t tot, uint16_t startY, uint16_t endY,
     uint16_t step = (endY - startY) / (tot + 1);
     uint16_t printY = startY + (step * cur);
 
+    // Estimate font height by reading the gliph | height
+    uint8_t h = gfx_getFontHeight(size);
+
+    // gfx_printBuffer() prints over the starting point
+    // Add half print_height to get vertically centered prints
+    printY += (h / 2);
+
     point_t start = {startX, printY};
     return gfx_printBuffer(start, size, alignment, color, text);
 }