minecraft-pi-reborn/mods/src/screenshot/screenshot.c

161 lines
4.1 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <png.h>
#include <libreborn/libreborn.h>
#include <GLES/gl.h>
#include <mods/screenshot/screenshot.h>
// Ensure Screenshots Folder Exists
static void ensure_screenshots_folder(char *screenshots) {
// Check Screenshots Folder
struct stat obj;
if (stat(screenshots, &obj) != 0 || !S_ISDIR(obj.st_mode)) {
// Create Screenshots Folder
int ret = mkdir(screenshots, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
if (ret != 0) {
// Unable To Create Folder
ERR("Error Creating Directory: %s: %s", screenshots, strerror(errno));
}
}
}
// 4 (Year) + 1 (Hyphen) + 2 (Month) + 1 (Hyphen) + 2 (Day) + 1 (Underscore) + 2 (Hour) + 1 (Period) + 2 (Minute) + 1 (Period) + 2 (Second) + 1 (Null Terminator)
#define TIME_SIZE 20
// Take Screenshot
static int save_png(const char *filename, unsigned char *pixels, int line_size, int width, int height) {
// Return value
int ret = 0;
// Variables
png_structp png = NULL;
png_infop info = NULL;
FILE *file = NULL;
png_colorp palette = NULL;
png_bytep rows[height];
for (int i = 0; i < height; ++i) {
rows[height - i - 1] = (png_bytep) (&pixels[i * line_size]);
}
// Init
png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png) {
ret = 1;
goto ret;
}
info = png_create_info_struct(png);
if (!info) {
ret = 1;
goto ret;
}
// Open File
file = fopen(filename, "wb");
if (!file) {
ret = 1;
goto ret;
}
// Prepare To Write
png_init_io(png, file);
png_set_IHDR(png, info, width, height, 8 /* Depth */, PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
palette = (png_colorp) png_malloc(png, PNG_MAX_PALETTE_LENGTH * sizeof(png_color));
if (!palette) {
ret = 1;
goto ret;
}
png_set_PLTE(png, info, palette, PNG_MAX_PALETTE_LENGTH);
png_write_info(png, info);
png_set_packing(png);
// Write
png_write_image(png, rows);
png_write_end(png, info);
ret:
// Free
if (palette != NULL) {
png_free(png, palette);
}
if (file != NULL) {
fclose(file);
}
if (png != NULL) {
png_destroy_write_struct(&png, &info);
}
// Return
return ret;
}
void screenshot_take(char *home) {
// Get Directory
char *screenshots = NULL;
safe_asprintf(&screenshots, "%s/screenshots", home);
// Get Timestamp
time_t rawtime;
struct tm *timeinfo;
time(&rawtime);
timeinfo = localtime(&rawtime);
char time[TIME_SIZE];
strftime(time, TIME_SIZE, "%Y-%m-%d_%H.%M.%S", timeinfo);
// Ensure Screenshots Folder Exists
ensure_screenshots_folder(screenshots);
// Prevent Overwriting Screenshots
int num = 1;
char *file = NULL;
safe_asprintf(&file, "%s/%s.png", screenshots, time);
while (access(file, F_OK) != -1) {
free(file);
file = NULL;
safe_asprintf(&file, "%s/%s-%i.png", screenshots, time, num);
num++;
}
// Get Image Size
GLint viewport[4];
glGetIntegerv(GL_VIEWPORT, viewport);
int x = viewport[0];
int y = viewport[1];
int width = viewport[2];
int height = viewport[3];
// Get Line Size
int line_size = width * 4;
{
// Handle Alignment
int alignment;
glGetIntegerv(GL_PACK_ALIGNMENT, &alignment);
// Round
int diff = line_size % alignment;
if (diff > 0) {
line_size = line_size + (alignment - diff);
}
}
int size = height * line_size;
// Read Pixels
unsigned char pixels[size];
glReadPixels(x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
// Save Image
if (save_png(file, pixels, line_size, width, height)) {
WARN("Screenshot Failed: %s", file);
} else {
INFO("Screenshot Saved: %s", file);
}
// Free
free(file);
free(screenshots);
}