Hi Guys

I see a pretty sample of a meter Ring do it for  Alan Senior. The link instructables is : http://www.instructables.com/id/Arduino-analogue-ring-meter-on-colour-TFT-display/?ALLSTEPS

The code use very interested thinks :

1) One is the prototype function:

int ringMeter(int value, int vmin, int vmax, int x, int y, int r, char *units, byte scheme). Whit this prototype you can do a lot of visual applications, its very greats

2)They use a triangle form to do the work, but digole doesn´t have this function.

use tft.fillTriangle(x0, y0, x1, y1, x2, y2, colour);

I modify the code to adapt to my digole display the code run, but i think that digole can do it more better. I use drawLineTo()  versus fillTringle but is not the same.

You can give me some idea that better?

The code:

 The images:

http://enrutador.com/IMG_0908.JPG

http://enrutador.com/IMG_0909.JPG

http://enrutador.com/IMG_0910.JPG

Thanks

I've adapted the Adafruit fillTriangle code to be used on my Digole OLED 160x128 displays, using the same technique of breaking the triangle down into a series of horizontal lines. I've optimized my version knowing the co-ordinates will never be larger than 8-bits.

I also have a similar ring-drawing functionality but I do it off-line and create a data table with 4 points for 2 triangles (1 polygon) and treat it as a triangle strip (so each addtional triangle is just 1 point). Then in my AVR code, I do something like this and avoid all sin/cos functions and multiplies/divides:

void color_wheel()
{
uint16_t index = 0;
uint8_t hue = 0;

const uint8_t* first = &sOLEDColorWheelTable[0];
uint8_t xpoint0 = VA_READ_PROGMEM_BYTE(first[0]);
uint8_t ypoint0 = VA_READ_PROGMEM_BYTE(first[1]);
uint8_t xpoint1 = VA_READ_PROGMEM_BYTE(first[2]);
uint8_t ypoint1 = VA_READ_PROGMEM_BYTE(first[3]);

// draw the color wheel based on hue values
do
{
// move to the next set of triangles in the table
index += 6;
const uint8_t* table = &sOLEDColorWheelTable[index];

// draw the triangle segments from the inner circle to the outer circle based on the hue's rgb values
uint8_t xpoint2 = VA_READ_PROGMEM_BYTE(table[0]);
uint8_t ypoint2 = VA_READ_PROGMEM_BYTE(table[1]);
uint8_t xpoint3 = VA_READ_PROGMEM_BYTE(table[2]);
uint8_t ypoint3 = VA_READ_PROGMEM_BYTE(table[3]);
uint16_t color = VA_READ_PROGMEM_WORD(table[4]);

// set the color for these segments
OLED.set_color16(color);

// draw the triangle segments
OLED.draw_triangle(xpoint0, ypoint0, xpoint1, ypoint1, xpoint2, ypoint2);
OLED.draw_triangle(xpoint1, ypoint1, xpoint2, ypoint2, xpoint3, ypoint3);

// rotate the points to progress through the triangle strip
xpoint0 = xpoint2;
ypoint0 = ypoint2;
xpoint1 = xpoint3;
ypoint1 = ypoint3;
}
while (++hue != 0);
}

 thanks Selgus  for sharing your experience and code poetry ¡¡¡¡