/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdint.h>
#include <sys/types.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/fb.h>
#include <linux/input.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <cutils/memory.h>
#include <asm-generic/mman.h>
#include <sys/mman.h>
#include <utils/threads.h>
#include <unistd.h>
#include <math.h>
using namespace android;
#ifndef FBIO_WAITFORVSYNC
#define FBIO_WAITFORVSYNC _IOW('F', 0x20, __u32)
#endif
struct Buffer {
size_t w;
size_t h;
size_t s;
union {
void* addr;
uint32_t* pixels;
};
};
void clearBuffer(Buffer* buf, uint32_t pixel) {
android_memset32(buf->pixels, pixel, buf->s * buf->h * 4);
}
void drawTwoPixels(Buffer* buf, uint32_t pixel, ssize_t x, ssize_t y, size_t w) {
if (y>0 && y<ssize_t(buf->h)) {
uint32_t* bits = buf->pixels + y * buf->s;
if (x>=0 && x<ssize_t(buf->w)) {
bits[x] = pixel;
}
ssize_t W(w);
if ((x+W)>=0 && (x+W)<ssize_t(buf->w)) {
bits[x+W] = pixel;
}
}
}
void drawHLine(Buffer* buf, uint32_t pixel, ssize_t x, ssize_t y, size_t w) {
if (y>0 && y<ssize_t(buf->h)) {
ssize_t W(w);
if (x<0) {
W += x;
x = 0;
}
if (x+w > buf->w) {
W = buf->w - x;
}
if (W>0) {
uint32_t* bits = buf->pixels + y * buf->s + x;
android_memset32(bits, pixel, W*4);
}
}
}
void drawRect(Buffer* buf, uint32_t pixel, ssize_t x, ssize_t y, size_t w, size_t h) {
ssize_t W(w), H(h);
if (x<0) {
w += x;
x = 0;
}
if (y<0) {
h += y;
y = 0;
}
if (x+w > buf->w) W = buf->w - x;
if (y+h > buf->h) H = buf->h - y;
if (W>0 && H>0) {
uint32_t* bits = buf->pixels + y * buf->s + x;
for (ssize_t i=0 ; i<H ; i++) {
android_memset32(bits, pixel, W*4);
bits += buf->s;
}
}
}
void drawCircle(Buffer* buf, uint32_t pixel,
size_t x0, size_t y0, size_t radius, bool filled = false) {
ssize_t f = 1 - radius;
ssize_t ddF_x = 1;
ssize_t ddF_y = -2 * radius;
ssize_t x = 0;
ssize_t y = radius;
if (filled) {
drawHLine(buf, pixel, x0-radius, y0, 2*radius);
} else {
drawTwoPixels(buf, pixel, x0-radius, y0, 2*radius);
}
while (x < y) {
if (f >= 0) {
y--;
ddF_y += 2;
f += ddF_y;
}
x++;
ddF_x += 2;
f += ddF_x;
if (filled) {
drawHLine(buf, pixel, x0-x, y0+y, 2*x);
drawHLine(buf, pixel, x0-x, y0-y, 2*x);
drawHLine(buf, pixel, x0-y, y0+x, 2*y);
drawHLine(buf, pixel, x0-y, y0-x, 2*y);
} else {
drawTwoPixels(buf, pixel, x0-x, y0+y, 2*x);
drawTwoPixels(buf, pixel, x0-x, y0-y, 2*x);
drawTwoPixels(buf, pixel, x0-y, y0+x, 2*y);
drawTwoPixels(buf, pixel, x0-y, y0-x, 2*y);
}
}
}
class TouchEvents {
class EventThread : public Thread {
int fd;
virtual bool threadLoop() {
input_event event;
int first_down = 0;
do {
read(fd, &event, sizeof(event));
if (event.type == EV_ABS) {
if (event.code == ABS_MT_TRACKING_ID) {
down = event.value == -1 ? 0 : 1;
first_down = down;
}
if (event.code == ABS_MT_POSITION_X) {
x = event.value;
}
if (event.code == ABS_MT_POSITION_Y) {
y = event.value;
}
}
} while (event.type == EV_SYN);
return true;
}
public:
int x, y, down;
EventThread() : Thread(false),
x(0), y(0), down(0)
{
fd = open("/dev/input/event1", O_RDONLY);
}
};
sp<EventThread> thread;
public:
TouchEvents() {
thread = new EventThread();
thread->run("EventThread", PRIORITY_URGENT_DISPLAY);
}
int getMostRecentPosition(int* x, int* y) {
*x = thread->x;
*y = thread->y;
return thread->down;
}
};
struct Queue {
struct position {
int x, y;
};
int index;
position q[16];
Queue() : index(0) { }
void push(int x, int y) {
index++;
index &= 0xF;
q[index].x = x;
q[index].y = y;
}
void get(int lag, int* x, int* y) {
const int i = (index - lag) & 0xF;
*x = q[i].x;
*y = q[i].y;
}
};
extern char *optarg;
extern int optind;
extern int optopt;
extern int opterr;
extern int optreset;
void usage(const char* name) {
printf("\nusage: %s [-h] [-l lag]\n", name);
}
int main(int argc, char** argv) {
fb_var_screeninfo vi;
fb_fix_screeninfo fi;
int lag = 0;
int fd = open("/dev/graphics/fb0", O_RDWR);
ioctl(fd, FBIOGET_VSCREENINFO, &vi);
ioctl(fd, FBIOGET_FSCREENINFO, &fi);
void* bits = mmap(0, fi.smem_len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
Buffer framebuffer;
framebuffer.w = vi.xres;
framebuffer.h = vi.yres;
framebuffer.s = fi.line_length / (vi.bits_per_pixel >> 3);
framebuffer.addr = bits;
int ch;
while ((ch = getopt(argc, argv, "hl:")) != -1) {
switch (ch) {
case 'l':
lag = atoi(optarg);
break;
case 'h':
default:
usage(argv[0]);
exit(0);
}
}
argc -= optind;
argv += optind;
TouchEvents touch;
Queue queue;
int x=0, y=0;
int lag_x=0, lag_y=0;
clearBuffer(&framebuffer, 0);
while (true) {
uint32_t crt = 0;
ioctl(fd, FBIO_WAITFORVSYNC, &crt);
// draw beam marker
drawRect(&framebuffer, 0x400000, framebuffer.w-2, 0, 2, framebuffer.h);
// erase screen
if (lag) {
drawCircle(&framebuffer, 0, lag_x, lag_y, 100);
drawHLine(&framebuffer, 0, 0, lag_y, 32);
}
drawCircle(&framebuffer, 0, x, y, 100, true);
drawHLine(&framebuffer, 0, 0, y, 32);
// draw a line at y=1000
drawHLine(&framebuffer, 0x808080, 0, 1000, framebuffer.w);
// get touch events
touch.getMostRecentPosition(&x, &y);
queue.push(x, y);
queue.get(lag, &lag_x, &lag_y);
if (lag) {
drawCircle(&framebuffer, 0x00FF00, lag_x, lag_y, 100);
drawHLine(&framebuffer, 0x00FF00, 0, lag_y, 32);
}
drawCircle(&framebuffer, 0xFFFFFF, x, y, 100, true);
drawHLine(&framebuffer, 0xFFFFFF, 0, y, 32);
// draw end of frame beam marker
drawRect(&framebuffer, 0x004000, framebuffer.w-2, 0, 2, framebuffer.h);
}
close(fd);
return 0;
}