You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
172 lines
5.9 KiB
172 lines
5.9 KiB
// Copyright 2021 Paul Cotter (@gr1mr3aver)
|
|
// Copyright 2021 Nick Brassel (@tzarc)
|
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
|
|
#include "qp.h"
|
|
#include "qp_internal.h"
|
|
#include "qp_comms.h"
|
|
#include "qp_draw.h"
|
|
|
|
// Utilize 8-way symmetry to draw circles
|
|
static bool qp_circle_helper_impl(painter_device_t device, uint16_t centerx, uint16_t centery, uint16_t offsetx, uint16_t offsety, bool filled) {
|
|
/*
|
|
Circles have the property of 8-way symmetry, so eight pixels can be drawn
|
|
for each computed [offsetx,offsety] given the center coordinates
|
|
represented by [centerx,centery].
|
|
|
|
For filled circles, we can draw horizontal lines between each pair of
|
|
pixels with the same final value of y.
|
|
|
|
Two special cases exist and have been optimized:
|
|
1) offsetx == offsety (the final point), makes half the coordinates
|
|
equivalent, so we can omit them (and the corresponding fill lines)
|
|
2) offsetx == 0 (the starting point) means that some horizontal lines
|
|
would be a single pixel in length, so we write individual pixels instead.
|
|
This also makes half the symmetrical points identical to their twins,
|
|
so we only need four points or two points and one line
|
|
*/
|
|
|
|
int16_t xpx = ((int16_t)centerx) + ((int16_t)offsetx);
|
|
int16_t xmx = ((int16_t)centerx) - ((int16_t)offsetx);
|
|
int16_t xpy = ((int16_t)centerx) + ((int16_t)offsety);
|
|
int16_t xmy = ((int16_t)centerx) - ((int16_t)offsety);
|
|
int16_t ypx = ((int16_t)centery) + ((int16_t)offsetx);
|
|
int16_t ymx = ((int16_t)centery) - ((int16_t)offsetx);
|
|
int16_t ypy = ((int16_t)centery) + ((int16_t)offsety);
|
|
int16_t ymy = ((int16_t)centery) - ((int16_t)offsety);
|
|
|
|
if (offsetx == 0) {
|
|
if (!qp_internal_setpixel_impl(device, centerx, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, centerx, ymy)) {
|
|
return false;
|
|
}
|
|
if (filled) {
|
|
if (!qp_internal_fillrect_helper_impl(device, xpy, centery, xmy, centery)) {
|
|
return false;
|
|
}
|
|
} else {
|
|
if (!qp_internal_setpixel_impl(device, xpy, centery)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmy, centery)) {
|
|
return false;
|
|
}
|
|
}
|
|
} else if (offsetx == offsety) {
|
|
if (filled) {
|
|
if (!qp_internal_fillrect_helper_impl(device, xpy, ypy, xmy, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_fillrect_helper_impl(device, xpy, ymy, xmy, ymy)) {
|
|
return false;
|
|
}
|
|
} else {
|
|
if (!qp_internal_setpixel_impl(device, xpy, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmy, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xpy, ymy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmy, ymy)) {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
} else {
|
|
if (filled) {
|
|
if (!qp_internal_fillrect_helper_impl(device, xpx, ypy, xmx, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_fillrect_helper_impl(device, xpx, ymy, xmx, ymy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_fillrect_helper_impl(device, xpy, ypx, xmy, ypx)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_fillrect_helper_impl(device, xpy, ymx, xmy, ymx)) {
|
|
return false;
|
|
}
|
|
} else {
|
|
if (!qp_internal_setpixel_impl(device, xpx, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmx, ypy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xpx, ymy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmx, ymy)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xpy, ypx)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmy, ypx)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xpy, ymx)) {
|
|
return false;
|
|
}
|
|
if (!qp_internal_setpixel_impl(device, xmy, ymx)) {
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
|
|
// Quantum Painter External API: qp_circle
|
|
|
|
bool qp_circle(painter_device_t device, uint16_t x, uint16_t y, uint16_t radius, uint8_t hue, uint8_t sat, uint8_t val, bool filled) {
|
|
qp_dprintf("qp_circle: entry\n");
|
|
struct painter_driver_t *driver = (struct painter_driver_t *)device;
|
|
if (!driver->validate_ok) {
|
|
qp_dprintf("qp_circle: fail (validation_ok == false)\n");
|
|
return false;
|
|
}
|
|
|
|
// plot the initial set of points for x, y and r
|
|
int16_t xcalc = 0;
|
|
int16_t ycalc = (int16_t)radius;
|
|
int16_t err = ((5 - (radius >> 2)) >> 2);
|
|
|
|
qp_internal_fill_pixdata(device, (radius * 2) + 1, hue, sat, val);
|
|
|
|
if (!qp_comms_start(device)) {
|
|
qp_dprintf("qp_circle: fail (could not start comms)\n");
|
|
return false;
|
|
}
|
|
|
|
bool ret = true;
|
|
if (!qp_circle_helper_impl(device, x, y, xcalc, ycalc, filled)) {
|
|
ret = false;
|
|
}
|
|
|
|
if (ret) {
|
|
while (xcalc < ycalc) {
|
|
xcalc++;
|
|
if (err < 0) {
|
|
err += (xcalc << 1) + 1;
|
|
} else {
|
|
ycalc--;
|
|
err += ((xcalc - ycalc) << 1) + 1;
|
|
}
|
|
if (!qp_circle_helper_impl(device, x, y, xcalc, ycalc, filled)) {
|
|
ret = false;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
qp_dprintf("qp_circle: %s\n", ret ? "ok" : "fail");
|
|
qp_comms_stop(device);
|
|
return ret;
|
|
}
|