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Ttelmah
Joined: 11 Mar 2010
Posts: 20059
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 Posted: Mon Jan 30, 2017 1:11 pm |
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| The obvious thing is your addressing is wrong. The first command is meant to carry the high nibble of the address. The second the low nibble. You are sending these the wrong way round.... |
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jamalavedra
Joined: 25 Oct 2016
Posts: 62
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| Posted: Tue Jan 31, 2017 11:32 am |
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Great, apparently it works now.
I am trying to use an algorithm (Bresenham's algorithm) in order to draw lines and make rectangles. The rectangles get drawn in the display and everything but they repeat several times column-wise.
Apparently it can't be anything to do with the code of the rectangle or lines because it does this regardless if I draw circles, rectangles or lines. Any thoughts on why this might happen?
Apart from that, I can't figure out what is the mistake in the code when writing letters or numbers. When used to write something, strings of lines appear were the letters should be.
| Code: |
bounding_box_t draw_text(char *string, unsigned char x, unsigned char y, unsigned char *font, unsigned char spacing) {
bounding_box_t ret;
bounding_box_t tmp;
ret.x1 = x;
ret.y1 = y;
spacing += 1;
// BUG: As we move right between chars we don't actually wipe the space
while (*string != 0) {
tmp = draw_char(*string++, x, y, font);
// Leave a single space between characters
x = tmp.x2 + spacing;
}
ret.x2 = tmp.x2;
ret.y2 = tmp.y2;
return ret;
}
bounding_box_t draw_char(unsigned char c, unsigned char x, unsigned char y, unsigned char *font) {
unsigned short pos;
unsigned char width;
bounding_box_t ret;
ret.x1 = x;
ret.y1 = y;
ret.x2 = x;
ret.y2 = y;
// Read first byte, should be 0x01 for proportional
if (font[FONT_HEADER_TYPE] != FONT_TYPE_PROPORTIONAL) return ret;
// Check second byte, should be 0x02 for "vertical ceiling"
if (font[FONT_HEADER_ORIENTATION] != FONT_ORIENTATION_VERTICAL_CEILING) return ret;
// Check that font start + number of bitmaps contains c
if (!(c >= font[FONT_HEADER_START] && c <= font[FONT_HEADER_START] + font[FONT_HEADER_LETTERS])) return ret;
// Adjust for start position of font vs. the char passed
c -= font[FONT_HEADER_START];
// Work out where in the array the character is
pos = font[c * FONT_HEADER_START + 5];
pos <<= 8;
pos |= font[c * FONT_HEADER_START + 6];
// Read first byte from this position, this gives letter width
width = font[pos];
// Draw left to right
unsigned char i;
for (i = 0; i < width; i++) {
// Draw top to bottom
for (j = 0; j < font[FONT_HEADER_HEIGHT]; j++) {
// Increment one data byte every 8 bits, or
// at the start of a new column HiTech optimizes
// the modulo, so no need to try and avoid it.
if (j % 8 == 0) pos++;
if (font[pos] & 1 << (j % 8)) {
glcd_pixel(x + i, y + j, 1);
} else {
glcd_pixel(x + i, y + j, 0);
}
}
}
ret.x2 = ret.x1 + width - 1;
// TODO: Return the actual height drawn, rather than the height of the
// font.
// ret.y2 = ret.y1 + height;
ret.y2 = ret.y1 + font[FONT_HEADER_HEIGHT];
return ret;
}
unsigned char text_height(unsigned char *string, unsigned char *font) {
// TODO: Possibly work out the actual pixel height. Letters with
// descenders (like 'g') are taller than letters without (like 'k')
// Height is stored in the header
return font[FONT_HEADER_HEIGHT];
}
unsigned char text_width(unsigned char *string, unsigned char *font, unsigned char spacing) {
unsigned char width = 0;
unsigned short pos;
unsigned char c;
// TODO: Implement for fixed width fonts
// Check font type, should be 0x01 for proportional
if (font[FONT_HEADER_TYPE] != FONT_TYPE_PROPORTIONAL) return 0;
while (*string != 0) {
c = *string++;
// Check that font start + number of bitmaps contains c
// TODO: Should we continue here but add 0 to width?
if (!(c >= font[FONT_HEADER_START] && c <= font[FONT_HEADER_START] + font[FONT_HEADER_LETTERS])) return 0;
// Adjust for start position of font vs. the char passed
c -= font[FONT_HEADER_START];
// Work out where in the array the character is
pos = font[c * FONT_HEADER_START + 5];
pos <<= 8;
pos |= font[c * FONT_HEADER_START + 6];
// Read first byte from this position, this gives letter width
width += font[pos];
// Allow for space between letters
width += spacing;
}
// The last letter wont have a space after it
return width - spacing;
}
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The font is not attached here but i don't think there is a mistake there.
thanks
jaume |
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temtronic
Joined: 01 Jul 2010
Posts: 9632
Location: Greensville,Ontario
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| Posted: Tue Jan 31, 2017 1:36 pm |
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Really, you've got to concentrate on ONE issue, fix it, then move onto the next. For a driver that was supposed to work, there's been a lot of 'patching' needed.
I'd get simple TEXT to be displayed, where I wanted it first....It _should_ be easy to get a GLCD to do that.
At least once it does you can USE the LCD to display data.
The problem with 'graphics' is that there is a LOT of 'math' involved,so unless you have code sending to a PC terminal program items like start, stop X,Y values it's very hard to debug what is wrong, code or hardware.
Jay |
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