Add drawLine function

radio/src/thirdparty/libopenui/src/bitmapbuffer.cpp

@@ -126,6 +126,57 @@ void BitmapBuffer::drawVerticalLine(coord_t x, coord_t y, coord_t h, uint8_t pat
   }
 }
 
+void BitmapBuffer::drawLine(coord_t x1, coord_t y1, coord_t x2, coord_t y2, uint8_t pat, LcdFlags att)
+{
+    // Offsets
+    x1 += this->offsetX;
+    y1 += this->offsetY;
+    x2 += this->offsetX;
+    y2 += this->offsetY;
+
+    pixel_t color = lcdColorTable[COLOR_IDX(att)];
+
+    int dx = x2 - x1;      /* the horizontal distance of the line */
+    int dy = y2 - y1;      /* the vertical distance of the line */
+    int dxabs = abs(dx);
+    int dyabs = abs(dy);
+    int sdx = sgn(dx);
+    int sdy = sgn(dy);
+    int x = dyabs >> 1;
+    int y = dxabs >> 1;
+    int px = x1;
+    int py = y1;
+
+    if (dxabs >= dyabs) {
+        /* the line is more horizontal than vertical */
+        for (int i = 0; i <= dxabs; i++) {
+            if ((1 << (px % 8)) & pat) {
+                drawPixel(px, py, color);
+            }
+            y += dyabs;
+            if (y >= dxabs) {
+                y -= dxabs;
+                py += sdy;
+            }
+            px += sdx;
+        }
+    } else {
+        /* the line is more vertical than horizontal */
+        for (int i = 0; i <= dyabs; i++) {
+            if ((1 << (py % 8)) & pat) {
+                drawPixel(px, py, color);
+            }
+            x += dxabs;
+            if (x >= dyabs) {
+                x -= dyabs;
+                px += sdx;
+            }
+            py += sdy;
+        }
+    }
+}
+
+
 void BitmapBuffer::drawRect(coord_t x, coord_t y, coord_t w, coord_t h, uint8_t thickness, uint8_t pat, LcdFlags att)
 {
   for (int i=0; i<thickness; i++) {
@@ -627,6 +678,8 @@ coord_t BitmapBuffer::drawNumber(coord_t x, coord_t y, int32_t val, LcdFlags fla
   return drawText(x, y, s, flags);
 }
 
+
+
 void drawSolidRect(BitmapBuffer * dc, coord_t x, coord_t y, coord_t w, coord_t h, uint8_t thickness, LcdFlags att)
 {
   dc->drawSolidFilledRect(x, y, thickness, h, att);

radio/src/thirdparty/libopenui/src/bitmapbuffer.h

@@ -327,6 +327,8 @@ class BitmapBuffer: public BitmapBufferBase<pixel_t>
 
     void drawVerticalLine(coord_t x, coord_t y, coord_t h, uint8_t pat = SOLID, LcdFlags flags = 0);
 
+    void drawLine(coord_t x1, coord_t y1, coord_t x2, coord_t y2, uint8_t pat, LcdFlags att);
+
     inline void drawSolidHorizontalLine(coord_t x, coord_t y, coord_t w, LcdFlags flags)
     {
       drawSolidFilledRect(x, y, w, 1, flags);

radio/src/thirdparty/libopenui/src/libopenui_helpers.h

@@ -53,6 +53,12 @@ inline int divRoundClosest(const int n, const int d)
     return ((n < 0) ^ (d < 0)) ? ((n - d/2)/d) : ((n + d/2)/d);
 }
 
+template<class T>
+inline T sgn(T a)
+{
+    return a > 0 ? 1 : (a < 0 ? -1 : 0);
+}
+
 // TODO duplicated code
 inline std::string TEXT_AT_INDEX(const char * val, uint8_t idx)
 {