st7735: Added text feature and documentation with license

Signed-off-by: Kiveisha Yevgeniy <yevgeniy.kiveisha@intel.com>

src/st7735/gfx.cxx

@@ -30,48 +30,50 @@
 
 using namespace upm;
 
-GFX::GFX (int width, int height) {
+GFX::GFX (int width, int height, uint8_t * screenBuffer, const unsigned char * font) : WIDTH(width), HEIGHT(height) {
     m_height = height;
     m_width  = width;
+    m_font   = font;
+    m_map    = screenBuffer;
 }
 
 GFX::~GFX () {
 }
 
-maa_result_t 
+maa_result_t
 GFX::setPixel (int x, int y, uint16_t color) {
     if((x < 0) ||(x >= m_width) || (y < 0) || (y >= m_height)) {
         return MAA_ERROR_UNSPECIFIED;
     }
-    
+
     int index = ((y * m_width) + x) * sizeof(uint16_t);
     m_map[index] = (uint8_t) (color >> 8);
     m_map[++index] = (uint8_t)(color);
-    
+
     return MAA_SUCCESS;
 }
 
-void 
+void
 GFX::fillScreen (uint16_t color) {
     fillRect(0, 0, m_width, m_height, color);
 }
 
-void 
+void
 GFX::fillRect (int16_t x, int16_t y, int16_t w, int16_t h, uint16_t color) {
     for (int16_t i=x; i<x+w; i++) {
         drawFastVLine(i, y, h, color);
     }
 }
 
-void 
+void
 GFX::drawFastVLine(int16_t x, int16_t y, int16_t h, uint16_t color) {
     drawLine(x, y, x, y+h-1, color);
 }
 
-void 
+void
 GFX::drawLine (int16_t x0, int16_t y0, int16_t x1, int16_t y1, uint16_t color) {
     int16_t steep = abs(y1 - y0) > abs(x1 - x0);
-    
+
     if (steep) {
         swap(x0, y0);
         swap(x1, y1);
@@ -109,14 +111,14 @@ GFX::drawLine (int16_t x0, int16_t y0, int16_t x1, int16_t y1, uint16_t color) {
     }
 }
 
-void 
+void
 GFX::drawTriangle(int16_t x0, int16_t y0, int16_t x1, int16_t y1, int16_t x2, int16_t y2, uint16_t color) {
     drawLine(x0, y0, x1, y1, color);
     drawLine(x1, y1, x2, y2, color);
     drawLine(x2, y2, x0, y0, color);
 }
 
-void 
+void
 GFX::drawCircle(int16_t x0, int16_t y0, int16_t r, uint16_t color) {
     int16_t f = 1 - r;
     int16_t ddF_x = 1;
@@ -136,7 +138,7 @@ GFX::drawCircle(int16_t x0, int16_t y0, int16_t r, uint16_t color) {
             f += ddF_y;
         }
         x++;
-        
+
         ddF_x += 2;
         f += ddF_x;
 
@@ -150,3 +152,80 @@ GFX::drawCircle(int16_t x0, int16_t y0, int16_t r, uint16_t color) {
         setPixel(x0 - y, y0 - x, color);
     }
 }
+
+void
+GFX::setCursor (int16_t x, int16_t y) {
+    m_cursorX = x;
+    m_cursorY = y;
+}
+
+void
+GFX::setTextColor (uint16_t textColor, uint16_t textBGColor) {
+    m_textColor   = textColor;
+    m_textBGColor = textBGColor;
+}
+
+void
+GFX::setTextSize (uint8_t size) {
+    m_textSize = (size > 0) ? size : 1;
+}
+
+void
+GFX::setTextWrap (uint8_t wrap) {
+    m_wrap = wrap;
+}
+
+void
+GFX::drawChar (int16_t x, int16_t y, uint8_t data, uint16_t color, uint16_t bg, uint8_t size) {
+    if( (x >= m_width)            || // Clip right
+        (y >= m_height)           || // Clip bottom
+        ((x + 6 * size - 1) < 0)  || // Clip left
+        ((y + 8 * size - 1) < 0))    // Clip top
+    return;
+
+    for (int8_t i=0; i<6; i++ ) {
+        uint8_t line;
+        if (i == 5) {
+            line = 0x0;
+        } else {
+            line = *(m_font+(data * 5)+i);
+            for (int8_t j = 0; j<8; j++) {
+                if (line & 0x1) {
+                    if (size == 1) // default size
+                        setPixel (x+i, y+j, color);
+                    else {  // big size
+                        fillRect (x+(i*size), y+(j*size), size, size, color);
+                    }
+                } else if (bg != color) {
+                    if (size == 1) // default size
+                        setPixel (x+i, y+j, bg);
+                    else {  // big size
+                        fillRect (x+i*size, y+j*size, size, size, bg);
+                    }
+                }
+                line >>= 1;
+            }
+        }
+    }
+}
+
+void
+GFX::print (std::string msg) {
+    int len = msg.length();
+
+    for (int idx = 0; idx < len; idx++) {
+        if (msg[idx] == '\n') {
+            m_cursorY += m_textSize * 8;
+            m_cursorX  = 0;
+        } else if (msg[idx] == '\r') {
+            // skip em
+        } else {
+            drawChar(m_cursorX, m_cursorY, msg[idx], m_textColor, m_textBGColor, m_textSize);
+            m_cursorX += m_textSize * 6;
+            if (m_wrap && (m_textColor > (m_width - m_textSize * 6))) {
+                m_cursorY += m_textSize * 8;
+                m_cursorX = 0;
+            }
+        }
+    }
+}