Files
libopencm3-examples/examples/stm32/f4/stm32f429i-discovery/lcd-serial/gfx.c

545 lines
13 KiB
C

/*
* This is the core graphics library for all our displays, providing a common
* set of graphics primitives (points, lines, circles, etc.). It needs to be
* paired with a hardware-specific library for each display device we carry
* (to handle the lower-level functions).
*
* Adafruit invests time and resources providing this open source code, please
* support Adafruit & open-source hardware by purchasing products from Adafruit!
*
* Copyright (c) 2013 Adafruit Industries. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Modified the AdaFruit library to be a C library, changed the font and
* generally munged it in a variety of ways, creating a reasonably quick
* and dirty way to put something "interesting" on the LCD display.
* --Chuck McManis (2013, 2014)
*
*/
#include <stdint.h>
#include <math.h>
#include <stdlib.h>
#include "gfx.h"
#include "font-7x12.c"
#define pgm_read_byte(addr) (*(const unsigned char *)(addr))
struct gfx_state __gfx_state;
void
gfx_drawPixel(int x, int y, uint16_t color)
{
if ((x < 0) || (x >= __gfx_state._width) ||
(y < 0) || (y >= __gfx_state._height)) {
return; /* off screen so don't draw it */
}
(__gfx_state.drawpixel)(x, y, color);
}
#define true 1
void
gfx_init(void (*pixel_func)(int, int, uint16_t), int width, int height)
{
__gfx_state._width = width;
__gfx_state._height = height;
__gfx_state.rotation = 0;
__gfx_state.cursor_y = __gfx_state.cursor_x = 0;
__gfx_state.textsize = 1;
__gfx_state.textcolor = 0;
__gfx_state.textbgcolor = 0xFFFF;
__gfx_state.wrap = true;
__gfx_state.drawpixel = pixel_func;
}
/* Draw a circle outline */
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;
int16_t ddF_y = -2 * r;
int16_t x = 0;
int16_t y = r;
gfx_drawPixel(x0 , y0+r, color);
gfx_drawPixel(x0 , y0-r, color);
gfx_drawPixel(x0+r, y0 , color);
gfx_drawPixel(x0-r, y0 , color);
while (x < y) {
if (f >= 0) {
y--;
ddF_y += 2;
f += ddF_y;
}
x++;
ddF_x += 2;
f += ddF_x;
gfx_drawPixel(x0 + x, y0 + y, color);
gfx_drawPixel(x0 - x, y0 + y, color);
gfx_drawPixel(x0 + x, y0 - y, color);
gfx_drawPixel(x0 - x, y0 - y, color);
gfx_drawPixel(x0 + y, y0 + x, color);
gfx_drawPixel(x0 - y, y0 + x, color);
gfx_drawPixel(x0 + y, y0 - x, color);
gfx_drawPixel(x0 - y, y0 - x, color);
}
}
void gfx_drawCircleHelper(int16_t x0, int16_t y0,
int16_t r, uint8_t cornername, uint16_t color)
{
int16_t f = 1 - r;
int16_t ddF_x = 1;
int16_t ddF_y = -2 * r;
int16_t x = 0;
int16_t y = r;
while (x < y) {
if (f >= 0) {
y--;
ddF_y += 2;
f += ddF_y;
}
x++;
ddF_x += 2;
f += ddF_x;
if (cornername & 0x4) {
gfx_drawPixel(x0 + x, y0 + y, color);
gfx_drawPixel(x0 + y, y0 + x, color);
}
if (cornername & 0x2) {
gfx_drawPixel(x0 + x, y0 - y, color);
gfx_drawPixel(x0 + y, y0 - x, color);
}
if (cornername & 0x8) {
gfx_drawPixel(x0 - y, y0 + x, color);
gfx_drawPixel(x0 - x, y0 + y, color);
}
if (cornername & 0x1) {
gfx_drawPixel(x0 - y, y0 - x, color);
gfx_drawPixel(x0 - x, y0 - y, color);
}
}
}
void gfx_fillCircle(int16_t x0, int16_t y0, int16_t r,
uint16_t color)
{
gfx_drawFastVLine(x0, y0 - r, 2*r+1, color);
gfx_fillCircleHelper(x0, y0, r, 3, 0, color);
}
/* Used to do circles and roundrects */
void gfx_fillCircleHelper(int16_t x0, int16_t y0, int16_t r,
uint8_t cornername, int16_t delta, uint16_t color)
{
int16_t f = 1 - r;
int16_t ddF_x = 1;
int16_t ddF_y = -2 * r;
int16_t x = 0;
int16_t y = r;
while (x < y) {
if (f >= 0) {
y--;
ddF_y += 2;
f += ddF_y;
}
x++;
ddF_x += 2;
f += ddF_x;
if (cornername & 0x1) {
gfx_drawFastVLine(x0+x, y0-y, 2*y+1+delta, color);
gfx_drawFastVLine(x0+y, y0-x, 2*x+1+delta, color);
}
if (cornername & 0x2) {
gfx_drawFastVLine(x0-x, y0-y, 2*y+1+delta, color);
gfx_drawFastVLine(x0-y, y0-x, 2*x+1+delta, color);
}
}
}
/* Bresenham's algorithm - thx wikpedia */
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);
}
if (x0 > x1) {
swap(x0, x1);
swap(y0, y1);
}
int16_t dx, dy;
dx = x1 - x0;
dy = abs(y1 - y0);
int16_t err = dx / 2;
int16_t ystep;
if (y0 < y1) {
ystep = 1;
} else {
ystep = -1;
}
for (; x0 <= x1; x0++) {
if (steep) {
gfx_drawPixel(y0, x0, color);
} else {
gfx_drawPixel(x0, y0, color);
}
err -= dy;
if (err < 0) {
y0 += ystep;
err += dx;
}
}
}
/* Draw a rectangle */
void gfx_drawRect(int16_t x, int16_t y,
int16_t w, int16_t h,
uint16_t color)
{
gfx_drawFastHLine(x, y, w, color);
gfx_drawFastHLine(x, y + h - 1, w, color);
gfx_drawFastVLine(x, y, h, color);
gfx_drawFastVLine(x + w - 1, y, h, color);
}
void gfx_drawFastVLine(int16_t x, int16_t y,
int16_t h, uint16_t color)
{
/* Update in subclasses if desired! */
gfx_drawLine(x, y, x, y + h - 1, color);
}
void gfx_drawFastHLine(int16_t x, int16_t y,
int16_t w, uint16_t color)
{
/* Update in subclasses if desired! */
gfx_drawLine(x, y, x + w - 1, y, color);
}
void gfx_fillRect(int16_t x, int16_t y, int16_t w, int16_t h,
uint16_t color)
{
/* Update in subclasses if desired! */
int16_t i;
for (i = x; i < x + w; i++) {
gfx_drawFastVLine(i, y, h, color);
}
}
void gfx_fillScreen(uint16_t color)
{
gfx_fillRect(0, 0, __gfx_state._width, __gfx_state._height, color);
}
/* Draw a rounded rectangle */
void gfx_drawRoundRect(int16_t x, int16_t y, int16_t w,
int16_t h, int16_t r, uint16_t color)
{
/* smarter version */
gfx_drawFastHLine(x + r , y , w - 2 * r, color); /* Top */
gfx_drawFastHLine(x + r , y + h - 1, w - 2 * r, color); /* Bottom */
gfx_drawFastVLine(x , y + r , h - 2 * r, color); /* Left */
gfx_drawFastVLine(x + w - 1, y + r , h - 2 * r, color); /* Right */
/* draw four corners */
gfx_drawCircleHelper(x + r , y + r , r, 1, color);
gfx_drawCircleHelper(x + w - r - 1, y + r , r, 2, color);
gfx_drawCircleHelper(x + w - r - 1, y + h - r - 1, r, 4, color);
gfx_drawCircleHelper(x + r , y + h - r - 1, r, 8, color);
}
/* Fill a rounded rectangle */
void gfx_fillRoundRect(int16_t x, int16_t y, int16_t w,
int16_t h, int16_t r, uint16_t color) {
/* smarter version */
gfx_fillRect(x + r, y, w - 2 * r, h, color);
/* draw four corners */
gfx_fillCircleHelper(x + w - r - 1, y + r, r, 1, h - 2 * r - 1, color);
gfx_fillCircleHelper(x + r , y + r, r, 2, h - 2 * r - 1, color);
}
/* Draw a triangle */
void gfx_drawTriangle(int16_t x0, int16_t y0,
int16_t x1, int16_t y1,
int16_t x2, int16_t y2, uint16_t color)
{
gfx_drawLine(x0, y0, x1, y1, color);
gfx_drawLine(x1, y1, x2, y2, color);
gfx_drawLine(x2, y2, x0, y0, color);
}
/* Fill a triangle */
void gfx_fillTriangle(int16_t x0, int16_t y0,
int16_t x1, int16_t y1,
int16_t x2, int16_t y2, uint16_t color)
{
int16_t a, b, y, last;
/* Sort coordinates by Y order (y2 >= y1 >= y0) */
if (y0 > y1) {
swap(y0, y1); swap(x0, x1);
}
if (y1 > y2) {
swap(y2, y1); swap(x2, x1);
}
if (y0 > y1) {
swap(y0, y1); swap(x0, x1);
}
/* Handle awkward all-on-same-line case as its own thing */
if (y0 == y2) {
a = b = x0;
if (x1 < a) {
a = x1;
} else if (x1 > b) {
b = x1;
}
if (x2 < a) {
a = x2;
} else if (x2 > b) {
b = x2;
}
gfx_drawFastHLine(a, y0, b - a + 1, color);
return;
}
int16_t
dx01 = x1 - x0,
dy01 = y1 - y0,
dx02 = x2 - x0,
dy02 = y2 - y0,
dx12 = x2 - x1,
dy12 = y2 - y1,
sa = 0,
sb = 0;
/* For upper part of triangle, find scanline crossings for segments
* 0-1 and 0-2. If y1=y2 (flat-bottomed triangle), the scanline y1
* is included here (and second loop will be skipped, avoiding a /0
* error there), otherwise scanline y1 is skipped here and handled
* in the second loop...which also avoids a /0 error here if y0=y1
* (flat-topped triangle).
*/
if (y1 == y2) {
last = y1; /* Include y1 scanline */
} else {
last = y1 - 1; /* Skip it */
}
for (y = y0; y <= last; y++) {
a = x0 + sa / dy01;
b = x0 + sb / dy02;
sa += dx01;
sb += dx02;
/* longhand:
a = x0 + (x1 - x0) * (y - y0) / (y1 - y0);
b = x0 + (x2 - x0) * (y - y0) / (y2 - y0);
*/
if (a > b) {
swap(a, b);
}
gfx_drawFastHLine(a, y, b - a + 1, color);
}
/* For lower part of triangle, find scanline crossings for segments
* 0-2 and 1-2. This loop is skipped if y1=y2.
*/
sa = dx12 * (y - y1);
sb = dx02 * (y - y0);
for (; y <= y2; y++) {
a = x1 + sa / dy12;
b = x0 + sb / dy02;
sa += dx12;
sb += dx02;
/* longhand:
a = x1 + (x2 - x1) * (y - y1) / (y2 - y1);
b = x0 + (x2 - x0) * (y - y0) / (y2 - y0);
*/
if (a > b) {
swap(a, b);
}
gfx_drawFastHLine(a, y, b - a + 1, color);
}
}
void gfx_drawBitmap(int16_t x, int16_t y,
const uint8_t *bitmap, int16_t w, int16_t h,
uint16_t color)
{
int16_t i, j, byteWidth = (w + 7) / 8;
for (j = 0; j < h; j++) {
for (i = 0; i < w; i++) {
if (pgm_read_byte(bitmap + j * byteWidth + i / 8) &
(128 >> (i & 7))) {
gfx_drawPixel(x + i, y + j, color);
}
}
}
}
void gfx_write(uint8_t c)
{
if (c == '\n') {
__gfx_state.cursor_y += __gfx_state.textsize * 12;
__gfx_state.cursor_x = 0;
} else if (c == '\r') {
/* skip em */
} else {
gfx_drawChar(__gfx_state.cursor_x, __gfx_state.cursor_y,
c, __gfx_state.textcolor, __gfx_state.textbgcolor,
__gfx_state.textsize);
__gfx_state.cursor_x += __gfx_state.textsize * 8;
if (__gfx_state.wrap &&
(__gfx_state.cursor_x > (__gfx_state._width -
__gfx_state.textsize*8))) {
__gfx_state.cursor_y += __gfx_state.textsize * 12;
__gfx_state.cursor_x = 0;
}
}
}
void gfx_puts(char *s)
{
while (*s) {
gfx_write(*s);
s++;
}
}
/* Draw a character */
void gfx_drawChar(int16_t x, int16_t y, unsigned char c,
uint16_t color, uint16_t bg, uint8_t size)
{
int8_t i, j, line;
int8_t descender;
unsigned const char *glyph;
glyph = &mcm_font[(c & 0x7f) * 9];
descender = (*glyph & 0x80) != 0;
for (i = 0; i < 12; i++) {
line = 0x00;
if (descender) {
if (i > 2) {
line = *(glyph + (i - 3));
}
} else {
if (i < 9) {
line = *(glyph + i);
}
}
line &= 0x7f;
for (j = 0; j < 8; j++) {
if (line & 0x80) {
if (size == 1) /* default size */
gfx_drawPixel(x+j, y+i, color);
else { /* big size */
gfx_fillRect(x+(j*size), y+(i*size),
size, size, color);
}
} else if (bg != color) {
if (size == 1) /* default size */
gfx_drawPixel(x+j, y+i, bg);
else { /* big size */
gfx_fillRect(x+j*size, y+i*size,
size, size, bg);
}
}
line <<= 1;
}
}
}
void gfx_setCursor(int16_t x, int16_t y)
{
__gfx_state.cursor_x = x;
__gfx_state.cursor_y = y;
}
void gfx_setTextSize(uint8_t s)
{
__gfx_state.textsize = (s > 0) ? s : 1;
}
void gfx_setTextColor(uint16_t c, uint16_t b)
{
__gfx_state.textcolor = c;
__gfx_state.textbgcolor = b;
}
void gfx_setTextWrap(uint8_t w)
{
__gfx_state.wrap = w;
}
uint8_t gfx_getRotation(void)
{
return __gfx_state.rotation;
}
void gfx_setRotation(uint8_t x)
{
__gfx_state.rotation = (x & 3);
switch (__gfx_state.rotation) {
case 0:
case 2:
__gfx_state._width = GFX_WIDTH;
__gfx_state._height = GFX_HEIGHT;
break;
case 1:
case 3:
__gfx_state._width = GFX_HEIGHT;
__gfx_state._height = GFX_WIDTH;
break;
}
}
/* Return the size of the display (per current rotation) */
uint16_t gfx_width(void)
{
return __gfx_state._width;
}
uint16_t gfx_height(void)
{
return __gfx_state._height;
}