Adafruit_GFX.cpp

00001 /*
00002 This is the core graphics library for all our displays,
00003 providing a common set of graphics primitives (points, lines, circles, etc.).
00004 It needs to be paired with a hardware-specific library for each display device we carry (to handle the lower-level functions).
00005  
00006 Adafruit invests time and resources providing this open source code,
00007 please support Adafruit and open-source hardware by purchasing products from Adafruit!
00008  
00009 Written by Limor Fried/Ladyada for Adafruit Industries.
00010 BSD license, check license.txt for more information.
00011 All text above must be included in any redistribution.
00012 */
00013  
00014 /*
00015  *  Modified by Tatsuki Fukuda 25/5/2014 for use in mbed
00016  */
00017  
00018 #include "Adafruit_GFX.h"
00019  
00020 // Draw a circle outline
00021 void Adafruit_GFX::drawCircle(int16_t x0, int16_t y0, int16_t r,
00022                               uint16_t color)
00023 {
00024     int16_t f = 1 - r;
00025     int16_t ddF_x = 1;
00026     int16_t ddF_y = -2 * r;
00027     int16_t x = 0;
00028     int16_t y = r;
00029  
00030     drawPixel(x0  , y0+r, color);
00031     drawPixel(x0  , y0-r, color);
00032     drawPixel(x0+r, y0  , color);
00033     drawPixel(x0-r, y0  , color);
00034  
00035     while (x<y) {
00036         if (f >= 0) {
00037             y--;
00038             ddF_y += 2;
00039             f += ddF_y;
00040         }
00041         x++;
00042         ddF_x += 2;
00043         f += ddF_x;
00044  
00045         drawPixel(x0 + x, y0 + y, color);
00046         drawPixel(x0 - x, y0 + y, color);
00047         drawPixel(x0 + x, y0 - y, color);
00048         drawPixel(x0 - x, y0 - y, color);
00049         drawPixel(x0 + y, y0 + x, color);
00050         drawPixel(x0 - y, y0 + x, color);
00051         drawPixel(x0 + y, y0 - x, color);
00052         drawPixel(x0 - y, y0 - x, color);
00053     }
00054 }
00055  
00056 void Adafruit_GFX::drawCircleHelper( int16_t x0, int16_t y0,
00057                                      int16_t r, uint8_t cornername, uint16_t color)
00058 {
00059     int16_t f     = 1 - r;
00060     int16_t ddF_x = 1;
00061     int16_t ddF_y = -2 * r;
00062     int16_t x     = 0;
00063     int16_t y     = r;
00064  
00065     while (x<y) {
00066         if (f >= 0) {
00067             y--;
00068             ddF_y += 2;
00069             f     += ddF_y;
00070         }
00071         x++;
00072         ddF_x += 2;
00073         f     += ddF_x;
00074         if (cornername & 0x4) {
00075             drawPixel(x0 + x, y0 + y, color);
00076             drawPixel(x0 + y, y0 + x, color);
00077         }
00078         if (cornername & 0x2) {
00079             drawPixel(x0 + x, y0 - y, color);
00080             drawPixel(x0 + y, y0 - x, color);
00081         }
00082         if (cornername & 0x8) {
00083             drawPixel(x0 - y, y0 + x, color);
00084             drawPixel(x0 - x, y0 + y, color);
00085         }
00086         if (cornername & 0x1) {
00087             drawPixel(x0 - y, y0 - x, color);
00088             drawPixel(x0 - x, y0 - y, color);
00089         }
00090     }
00091 }
00092  
00093 void Adafruit_GFX::fillCircle(int16_t x0, int16_t y0, int16_t r,
00094                               uint16_t color)
00095 {
00096     drawFastVLine(x0, y0-r, 2*r+1, color);
00097     fillCircleHelper(x0, y0, r, 3, 0, color);
00098 }
00099  
00100 // Used to do circles and roundrects
00101 void Adafruit_GFX::fillCircleHelper(int16_t x0, int16_t y0, int16_t r,
00102                                     uint8_t cornername, int16_t delta, uint16_t color)
00103 {
00104  
00105     int16_t f     = 1 - r;
00106     int16_t ddF_x = 1;
00107     int16_t ddF_y = -2 * r;
00108     int16_t x     = 0;
00109     int16_t y     = r;
00110  
00111     while (x<y) {
00112         if (f >= 0) {
00113             y--;
00114             ddF_y += 2;
00115             f     += ddF_y;
00116         }
00117         x++;
00118         ddF_x += 2;
00119         f     += ddF_x;
00120  
00121         if (cornername & 0x1) {
00122             drawFastVLine(x0+x, y0-y, 2*y+1+delta, color);
00123             drawFastVLine(x0+y, y0-x, 2*x+1+delta, color);
00124         }
00125         if (cornername & 0x2) {
00126             drawFastVLine(x0-x, y0-y, 2*y+1+delta, color);
00127             drawFastVLine(x0-y, y0-x, 2*x+1+delta, color);
00128         }
00129     }
00130 }
00131  
00132 // Bresenham's algorithm - thx wikpedia
00133 void Adafruit_GFX::drawLine(int16_t x0, int16_t y0,
00134                             int16_t x1, int16_t y1,
00135                             uint16_t color)
00136 {
00137     int16_t steep = abs(y1 - y0) > abs(x1 - x0);
00138     if (steep) {
00139         swap(x0, y0);
00140         swap(x1, y1);
00141     }
00142  
00143     if (x0 > x1) {
00144         swap(x0, x1);
00145         swap(y0, y1);
00146     }
00147  
00148     int16_t dx, dy;
00149     dx = x1 - x0;
00150     dy = abs(y1 - y0);
00151  
00152     int16_t err = dx / 2;
00153     int16_t ystep;
00154  
00155     if (y0 < y1) {
00156         ystep = 1;
00157     } else {
00158         ystep = -1;
00159     }
00160  
00161     for (; x0<=x1; x0++) {
00162         if (steep) {
00163             drawPixel(y0, x0, color);
00164         } else {
00165             drawPixel(x0, y0, color);
00166         }
00167         err -= dy;
00168         if (err < 0) {
00169             y0 += ystep;
00170             err += dx;
00171         }
00172     }
00173 }
00174  
00175 // Draw a rectangle
00176 void Adafruit_GFX::drawRect(int16_t x, int16_t y,
00177                             int16_t w, int16_t h,
00178                             uint16_t color)
00179 {
00180     drawFastHLine(x, y, w, color);
00181     drawFastHLine(x, y+h-1, w, color);
00182     drawFastVLine(x, y, h, color);
00183     drawFastVLine(x+w-1, y, h, color);
00184 }
00185  
00186 void Adafruit_GFX::drawFastVLine(int16_t x, int16_t y,
00187                                  int16_t h, uint16_t color)
00188 {
00189     // Update in subclasses if desired!
00190     drawLine(x, y, x, y+h-1, color);
00191 }
00192  
00193 void Adafruit_GFX::drawFastHLine(int16_t x, int16_t y,
00194                                  int16_t w, uint16_t color)
00195 {
00196     // Update in subclasses if desired!
00197     drawLine(x, y, x+w-1, y, color);
00198 }
00199  
00200 void Adafruit_GFX::fillRect(int16_t x, int16_t y, int16_t w, int16_t h,
00201                             uint16_t color)
00202 {
00203     // Update in subclasses if desired!
00204     for (int16_t i=x; i<x+w; i++) {
00205         drawFastVLine(i, y, h, color);
00206     }
00207 }
00208  
00209 void Adafruit_GFX::fillScreen(uint16_t color)
00210 {
00211     fillRect(0, 0, _width, _height, color);
00212     clearTextBuf(0,0,_width,_height);
00213 }
00214  
00215 // Draw a rounded rectangle
00216 void Adafruit_GFX::drawRoundRect(int16_t x, int16_t y, int16_t w,
00217                                  int16_t h, int16_t r, uint16_t color)
00218 {
00219     // smarter version
00220     drawFastHLine(x+r  , y    , w-2*r, color); // Top
00221     drawFastHLine(x+r  , y+h-1, w-2*r, color); // Bottom
00222     drawFastVLine(x    , y+r  , h-2*r, color); // Left
00223     drawFastVLine(x+w-1, y+r  , h-2*r, color); // Right
00224     // draw four corners
00225     drawCircleHelper(x+r    , y+r    , r, 1, color);
00226     drawCircleHelper(x+w-r-1, y+r    , r, 2, color);
00227     drawCircleHelper(x+w-r-1, y+h-r-1, r, 4, color);
00228     drawCircleHelper(x+r    , y+h-r-1, r, 8, color);
00229 }
00230  
00231 // Fill a rounded rectangle
00232 void Adafruit_GFX::fillRoundRect(int16_t x, int16_t y, int16_t w,
00233                                  int16_t h, int16_t r, uint16_t color)
00234 {
00235     // smarter version
00236     fillRect(x+r, y, w-2*r, h, color);
00237  
00238     // draw four corners
00239     fillCircleHelper(x+w-r-1, y+r, r, 1, h-2*r-1, color);
00240     fillCircleHelper(x+r    , y+r, r, 2, h-2*r-1, color);
00241 }
00242  
00243 // Draw a triangle
00244 void Adafruit_GFX::drawTriangle(int16_t x0, int16_t y0,
00245                                 int16_t x1, int16_t y1,
00246                                 int16_t x2, int16_t y2, uint16_t color)
00247 {
00248     drawLine(x0, y0, x1, y1, color);
00249     drawLine(x1, y1, x2, y2, color);
00250     drawLine(x2, y2, x0, y0, color);
00251 }
00252  
00253 // Fill a triangle
00254 void Adafruit_GFX::fillTriangle ( int16_t x0, int16_t y0,
00255                                   int16_t x1, int16_t y1,
00256                                   int16_t x2, int16_t y2, uint16_t color)
00257 {
00258  
00259     int16_t a, b, y, last;
00260  
00261     // Sort coordinates by Y order (y2 >= y1 >= y0)
00262     if (y0 > y1) {
00263         swap(y0, y1);
00264         swap(x0, x1);
00265     }
00266     if (y1 > y2) {
00267         swap(y2, y1);
00268         swap(x2, x1);
00269     }
00270     if (y0 > y1) {
00271         swap(y0, y1);
00272         swap(x0, x1);
00273     }
00274  
00275     if(y0 == y2) { // Handle awkward all-on-same-line case as its own thing
00276         a = b = x0;
00277         if(x1 < a)      a = x1;
00278         else if(x1 > b) b = x1;
00279         if(x2 < a)      a = x2;
00280         else if(x2 > b) b = x2;
00281         drawFastHLine(a, y0, b-a+1, color);
00282         return;
00283     }
00284  
00285     int16_t
00286     dx01 = x1 - x0,
00287     dy01 = y1 - y0,
00288     dx02 = x2 - x0,
00289     dy02 = y2 - y0,
00290     dx12 = x2 - x1,
00291     dy12 = y2 - y1,
00292     sa   = 0,
00293     sb   = 0;
00294  
00295     // For upper part of triangle, find scanline crossings for segments
00296     // 0-1 and 0-2.  If y1=y2 (flat-bottomed triangle), the scanline y1
00297     // is included here (and second loop will be skipped, avoiding a /0
00298     // error there), otherwise scanline y1 is skipped here and handled
00299     // in the second loop...which also avoids a /0 error here if y0=y1
00300     // (flat-topped triangle).
00301     if(y1 == y2) last = y1;   // Include y1 scanline
00302     else         last = y1-1; // Skip it
00303  
00304     for(y=y0; y<=last; y++) {
00305         a   = x0 + sa / dy01;
00306         b   = x0 + sb / dy02;
00307         sa += dx01;
00308         sb += dx02;
00309         /* longhand:
00310         a = x0 + (x1 - x0) * (y - y0) / (y1 - y0);
00311         b = x0 + (x2 - x0) * (y - y0) / (y2 - y0);
00312         */
00313         if(a > b) swap(a,b);
00314         drawFastHLine(a, y, b-a+1, color);
00315     }
00316  
00317     // For lower part of triangle, find scanline crossings for segments
00318     // 0-2 and 1-2.  This loop is skipped if y1=y2.
00319     sa = dx12 * (y - y1);
00320     sb = dx02 * (y - y0);
00321     for(; y<=y2; y++) {
00322         a   = x1 + sa / dy12;
00323         b   = x0 + sb / dy02;
00324         sa += dx12;
00325         sb += dx02;
00326         /* longhand:
00327         a = x1 + (x2 - x1) * (y - y1) / (y2 - y1);
00328         b = x0 + (x2 - x0) * (y - y0) / (y2 - y0);
00329         */
00330         if(a > b) swap(a,b);
00331         drawFastHLine(a, y, b-a+1, color);
00332     }
00333 }
00334  
00335 void Adafruit_GFX::drawBitmap(int16_t x, int16_t y, const uint8_t *bitmap, int16_t w, int16_t h, uint16_t color)
00336 {
00337     int16_t i, j;
00338     for(j=0; j<h; j++) {
00339         for(i=0; i<w; i++ ) {
00340             if(bitmap[i+(j/8)*w]& _BV(j%8) )
00341                 drawPixel(x+i, y+j, color);
00342         }
00343     }
00344 }
00345  
00346 size_t Adafruit_GFX::writeChar(uint8_t c)
00347 {
00348     if (c == '\n') {
00349         cursor_y += textsize*8;
00350         cursor_x  = 0;
00351     } else if (c == '\r') {
00352         cursor_x  = 0;
00353     } else {
00354         drawChar(cursor_x, cursor_y, c, textcolor, textbgcolor, textsize);
00355         cursor_x += textsize*6;
00356         if (wrap && (cursor_x > (_width - textsize*6))) {
00357             cursor_y += textsize*8;
00358             cursor_x = 0;
00359         }
00360     }
00361     return 1;
00362 }
00363  
00364 // Draw a character
00365 void Adafruit_GFX::drawChar(int16_t x, int16_t y, unsigned char c, uint16_t color, uint16_t bg, uint8_t size)
00366 {
00367     bool to_print;
00368     if((x >= _width)|| // Clip right
00369             (y >= _height)|| // Clip bottom
00370             ((x + 6 * size - 1) < 0) || // Clip left
00371             ((y + 8 * size - 1) < 0))// Clip top
00372         return;
00373  
00374     int x_temp,y_temp;
00375     for (int8_t i=0; i<6; i++ ) {
00376         uint8_t line;
00377         if (i == 5)
00378             line = 0x0;
00379         else
00380             line = font[(c*5)+i];
00381         for (int8_t j = 0; j<8; j++) {
00382             to_print=line & 0x1;
00383             if (size ==1) { //default size
00384                 if (to_print & !textbuf[x+i][y+j]) {
00385                     drawPixel(x+i, y+j, color);
00386                     textbuf[x+i][y+j]=true; 
00387                     //fillRect(x+(i*size), y+(j*size), size, size, color);
00388                 } else if (!to_print & textbuf[x+i][y+j]) {
00389                     drawPixel(x+i, y+j, bg);
00390                     textbuf[x+i][y+j]=false;
00391                     //fillRect(x+i*size, y+j*size, size, size, bg);
00392                 }
00393             } else {
00394                 if(to_print) {
00395                     for (int8_t ii = 0; ii<size; ii++) {
00396                         for (int8_t jj = 0; jj<size; jj++) {
00397                             x_temp=x+i*size+ii;
00398                             y_temp=y+j*size+jj;
00399                             if(!textbuf[x_temp][y_temp]) {
00400                                 drawPixel(x_temp, y_temp, color);
00401                                 textbuf[x_temp][y_temp]=true;
00402                             }
00403                         }
00404                     }
00405                 } else if(!to_print){
00406                     for (int8_t ii = 0; ii<size; ii++) {
00407                         for (int8_t jj = 0; jj<size; jj++) {
00408                             x_temp=x+i*size+ii;
00409                             y_temp=y+j*size+jj;
00410                             if(textbuf[x_temp][y_temp]) {
00411                                 drawPixel(x_temp, y_temp, bg);
00412                                 textbuf[x_temp][y_temp]=false;
00413                             }
00414                         }
00415                     }
00416                 }
00417             }
00418             line >>= 1;
00419         }
00420     }
00421 }
00422 
00423 void Adafruit_GFX::clearTextBuf(int x,int y,int w,int h) {
00424     for (int i=x; i<w; i++ ) {
00425         for (int j=y; j<h; j++ ) {
00426             textbuf[i][j]=false;
00427         }
00428     }
00429 }
00430 
00431 void Adafruit_GFX::clearText() {
00432     for (int i=0; i<_rawWidth; i++ ) {
00433         for (int j=0; j<_rawHeight; j++ ) {
00434             if(textbuf[i][j]) {
00435                 //Change color of pixel to background color
00436                 drawPixel(i, j, textbgcolor);
00437                 //Update buffer value
00438                 textbuf[i][j]=false;
00439             }
00440         }
00441     }
00442 }
00443 
00444 
00445 void Adafruit_GFX::invertDisplay(bool i)
00446 {
00447     // Do nothing, must be subclassed if supported
00448 }