//
// SuperTux (Statistics module)
// Copyright (C) 2004 Ricardo Cruz <rick2@aeiou.pt>
-// Copyright (C) 2006 Ondrej Hosek <white.timberwolf@aon.at>
+// Copyright (C) 2006 Ondrej Hosek <ondra.hosek@gmail.com>
+// Copyright (C) 2006 Christoph Sommer <christoph.sommer@2006.expires.deltadevelopment.de>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
-//
+//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
#include <config.h>
+#include <assert.h>
+#include <math.h>
+#include <sstream>
+#include <iomanip>
+#include <limits>
#include "video/drawing_context.hpp"
#include "gettext.hpp"
+#include "lisp/writer.hpp"
#include "lisp/lisp.hpp"
#include "resources.hpp"
#include "main.hpp"
#include "statistics.hpp"
-
-Statistics global_stats;
-
-std::string
-stat_name_to_string(int stat_enum)
-{
- switch(stat_enum)
- {
-// case SCORE_STAT:
-// return "score";
- case COINS_COLLECTED_STAT:
- return "coins-collected";
- case BADGUYS_KILLED_STAT:
- return "badguys-killed";
- case TIME_NEEDED_STAT:
- return "time-needed";;
- }
- return "";
+#include "log.hpp"
+#include "scripting/squirrel_util.hpp"
+
+namespace {
+ const int nv_coins = std::numeric_limits<int>::min();
+ const int nv_badguys = std::numeric_limits<int>::min();
+ const float nv_time = std::numeric_limits<float>::max();
+ const int nv_secrets = std::numeric_limits<int>::min();
}
-int
-my_min(int a, int b)
-{
-if(a == -1)
- return b;
-if(b == -1)
- return a;
-return std::min(a, b);
-}
+float WMAP_INFO_LEFT_X;
+float WMAP_INFO_RIGHT_X;
+float WMAP_INFO_TOP_Y1;
+float WMAP_INFO_TOP_Y2;
-Statistics::Statistics()
+Statistics::Statistics() : coins(nv_coins), total_coins(nv_coins), badguys(nv_badguys), total_badguys(nv_badguys), time(nv_time), secrets(nv_secrets), total_secrets(nv_secrets), valid(true)
{
- display_stat = 1;
-
- for(int i = 0; i < NUM_STATS; i++)
- for(int j = 0; j < 2; j++)
- stats[i][j] = -1;
+ WMAP_INFO_LEFT_X = (SCREEN_WIDTH/2 + 80) + 32;
+ WMAP_INFO_RIGHT_X = SCREEN_WIDTH/2 + 368;
+ WMAP_INFO_TOP_Y1 = SCREEN_HEIGHT/2 + 172 - 16;
+ WMAP_INFO_TOP_Y2 = SCREEN_HEIGHT/2 + 172;
}
Statistics::~Statistics()
{
}
+/*
void
Statistics::parse(const lisp::Lisp& reader)
{
- for(int i = 0; i < NUM_STATS; i++) {
- reader.get(stat_name_to_string(i).c_str(), stats[i][SPLAYER]);
- reader.get((stat_name_to_string(i) + "-total").c_str(), stats[i][STOTAL]);
- }
+ reader.get("coins-collected", coins);
+ reader.get("coins-collected-total", total_coins);
+ reader.get("badguys-killed", badguys);
+ reader.get("badguys-killed-total", total_badguys);
+ reader.get("time-needed", time);
+ reader.get("secrets-found", secrets);
+ reader.get("secrets-found-total", total_secrets);
}
void
Statistics::write(lisp::Writer& writer)
{
- for(int i = 0; i < NUM_STATS; i++) {
- writer.write_int(stat_name_to_string(i), stats[i][SPLAYER]);
- writer.write_int(stat_name_to_string(i) + "-total", stats[i][STOTAL]);
- }
+ writer.write("coins-collected", coins);
+ writer.write("coins-collected-total", total_coins);
+ writer.write("badguys-killed", badguys);
+ writer.write("badguys-killed-total", total_badguys);
+ writer.write("time-needed", time);
+ writer.write("secrets-found", secrets);
+ writer.write("secrets-found-total", total_secrets);
}
+*/
-//define TOTAL_DISPLAY_TIME 3400
-//define FADING_TIME 600
-
-#define TOTAL_DISPLAY_TIME 5
-#define FADING_TIME 1
-
-#define WMAP_INFO_LEFT_X 520
-#define WMAP_INFO_RIGHT_X 740
+void
+Statistics::serialize_to_squirrel(HSQUIRRELVM vm)
+{
+ // TODO: there's some bug in the unserialization routines that breaks stuff when an empty statistics table is written, so -- as a workaround -- let's make sure we will actually write something first
+ if (!((coins != nv_coins) || (total_coins != nv_coins) || (badguys != nv_badguys) || (total_badguys != nv_badguys) || (time != nv_time) || (secrets != nv_secrets) || (total_secrets != nv_secrets))) return;
+
+ sq_pushstring(vm, "statistics", -1);
+ sq_newtable(vm);
+ if (coins != nv_coins) Scripting::store_int(vm, "coins-collected", coins);
+ if (total_coins != nv_coins) Scripting::store_int(vm, "coins-collected-total", total_coins);
+ if (badguys != nv_badguys) Scripting::store_int(vm, "badguys-killed", badguys);
+ if (total_badguys != nv_badguys) Scripting::store_int(vm, "badguys-killed-total", total_badguys);
+ if (time != nv_time) Scripting::store_float(vm, "time-needed", time);
+ if (secrets != nv_secrets) Scripting::store_int(vm, "secrets-found", secrets);
+ if (total_secrets != nv_secrets) Scripting::store_int(vm, "secrets-found-total", total_secrets);
+ sq_createslot(vm, -3);
+}
void
-Statistics::draw_worldmap_info(DrawingContext& context)
+Statistics::unserialize_from_squirrel(HSQUIRRELVM vm)
{
- if(stats[COINS_COLLECTED_STAT][SPLAYER] == -1) // not initialized yet
+ sq_pushstring(vm, "statistics", -1);
+ if(SQ_FAILED(sq_get(vm, -2))) {
return;
-
-// if(timer.check())
- if (!timer.started())
- {
- timer.start(TOTAL_DISPLAY_TIME);
- display_stat++;
- if(display_stat >= NUM_STATS)
- display_stat = 0;
-
- if((display_stat == TIME_NEEDED_STAT) && (stats[TIME_NEEDED_STAT][STOTAL] == -1))
- { // no timer in level
- display_stat++;
- if(display_stat >= NUM_STATS)
- display_stat = 0;
- }
}
-
- char str[128];
-
- context.draw_text(white_small_text, _("- Best Level Statistics -"),
- Vector((WMAP_INFO_LEFT_X + WMAP_INFO_RIGHT_X) / 2, 470),
- CENTER_ALLIGN, LAYER_GUI);
-
- // Score has been removed
- //sprintf(str, _("Max score:"));
- //context.draw_text(white_small_text, str, Vector(WMAP_INFO_LEFT_X, 490), LEFT_ALLIGN, LAYER_GUI);
-
- //sprintf(str, "%d", stats[SCORE_STAT][SPLAYER]);
- //context.draw_text(white_small_text, str, Vector(WMAP_INFO_RIGHT_X, 490), RIGHT_ALLIGN, LAYER_GUI);
-
- float alpha;
- if(timer.get_timegone() < FADING_TIME)
- alpha = (timer.get_timegone() * 1.0f / FADING_TIME);
- else if(timer.get_timeleft() < FADING_TIME)
- alpha = (timer.get_timeleft() * 1.0f / FADING_TIME);
- else
- alpha = 1.0f;
-
- context.push_transform();
- context.set_alpha(alpha);
-
- if(display_stat == COINS_COLLECTED_STAT)
- sprintf(str, _("Max coins collected:"));
- else if(display_stat == BADGUYS_KILLED_STAT)
- sprintf(str, _("Max fragging:"));
- else// if(display_stat == TIME_NEEDED_STAT)
- sprintf(str, _("Min time needed:"));
-
- // y == 508 before score was removed
- context.draw_text(white_small_text, str, Vector(WMAP_INFO_LEFT_X, 490), LEFT_ALLIGN, LAYER_GUI);
-
- if(display_stat == COINS_COLLECTED_STAT)
- sprintf(str, "%d/%d", stats[COINS_COLLECTED_STAT][SPLAYER],
- stats[COINS_COLLECTED_STAT][STOTAL]);
- else if(display_stat == BADGUYS_KILLED_STAT)
- sprintf(str, "%d/%d", stats[BADGUYS_KILLED_STAT][SPLAYER],
- stats[BADGUYS_KILLED_STAT][STOTAL]);
- else// if(display_stat == TIME_NEEDED_STAT)
- sprintf(str, "%d/%d", stats[TIME_NEEDED_STAT][SPLAYER],
- stats[TIME_NEEDED_STAT][STOTAL]);
-
- context.draw_text(white_small_text, str, Vector(WMAP_INFO_RIGHT_X, 490), RIGHT_ALLIGN, LAYER_GUI);
-
- context.pop_transform();
+ Scripting::get_int(vm, "coins-collected", coins);
+ Scripting::get_int(vm, "coins-collected-total", total_coins);
+ Scripting::get_int(vm, "badguys-killed", badguys);
+ Scripting::get_int(vm, "badguys-killed-total", total_badguys);
+ Scripting::get_float(vm, "time-needed", time);
+ Scripting::get_int(vm, "secrets-found", secrets);
+ Scripting::get_int(vm, "secrets-found-total", total_secrets);
+ sq_pop(vm, 1);
}
void
-Statistics::draw_message_info(DrawingContext& context, std::string title)
+Statistics::draw_worldmap_info(DrawingContext& context)
{
- if(stats[COINS_COLLECTED_STAT][SPLAYER] == -1) // not initialized yet
- return;
-
- context.draw_text(gold_text, title, Vector(SCREEN_WIDTH/2, 410), CENTER_ALLIGN, LAYER_GUI);
+ // skip draw if level was never played
+ if (coins == nv_coins) return;
- char str[128];
+ // skip draw if stats were declared invalid
+ if (!valid) return;
- //sprintf(str, _( "Max score: %d"), stats[SCORE_STAT][SPLAYER]);
- //context.draw_text(white_text, str, Vector(SCREEN_WIDTH/2, 450), CENTER_ALLIGN, LAYER_GUI);
+ context.draw_text(small_font, std::string("- ") + _("Best Level Statistics") + " -", Vector((WMAP_INFO_LEFT_X + WMAP_INFO_RIGHT_X) / 2, WMAP_INFO_TOP_Y1), ALIGN_CENTER, LAYER_GUI,Statistics::header_color);
- for(int i = 0; i < NUM_STATS; i++)
+ std::string caption_buf;
+ std::string stat_buf;
+ float posy = WMAP_INFO_TOP_Y2;
+ for (int stat_no = 0; stat_no < 4; stat_no++) {
+ switch (stat_no)
{
- if(i == COINS_COLLECTED_STAT)
- sprintf(str, _("Max coins collected: %d / %d"),
- stats[COINS_COLLECTED_STAT][SPLAYER],
- stats[COINS_COLLECTED_STAT][STOTAL]);
- else if(i == BADGUYS_KILLED_STAT)
- sprintf(str, _("Max fragging: %d / %d"),
- stats[BADGUYS_KILLED_STAT][SPLAYER],
- stats[BADGUYS_KILLED_STAT][STOTAL]);
- else if((i == TIME_NEEDED_STAT) && (stats[TIME_NEEDED_STAT][STOTAL] != -1))
- sprintf(str, _("Min time needed: %d / %d"),
- stats[TIME_NEEDED_STAT][SPLAYER],
- stats[TIME_NEEDED_STAT][STOTAL]);
- else
- continue;
-
-
- // y == (462 + i*18) before score removal
- context.draw_text(white_small_text, str, Vector(SCREEN_WIDTH/2, 450 + (i+1)*18), CENTER_ALLIGN, LAYER_GUI);
+ case 0:
+ caption_buf = _("Max coins collected:");
+ stat_buf = coins_to_string(coins, total_coins);
+ break;
+ case 1:
+ caption_buf = _("Max fragging:");
+ stat_buf = frags_to_string(badguys, total_badguys);
+ break;
+ case 2:
+ caption_buf = _("Min time needed:");
+ stat_buf = time_to_string(time);
+ break;
+ case 3:
+ caption_buf = _("Max secrets found:");
+ stat_buf = secrets_to_string(secrets, total_secrets);
+ break;
+ default:
+ log_debug << "Invalid stat requested to be drawn" << std::endl;
+ break;
}
+
+ context.draw_text(small_font, caption_buf, Vector(WMAP_INFO_LEFT_X, posy), ALIGN_LEFT, LAYER_GUI, Statistics::header_color);
+ context.draw_text(small_font, stat_buf, Vector(WMAP_INFO_RIGHT_X, posy), ALIGN_RIGHT, LAYER_GUI, Statistics::header_color);
+ posy += small_font->get_height() + 2;
+ }
+
}
-void
+void
Statistics::draw_endseq_panel(DrawingContext& context, Statistics* best_stats, Surface* backdrop)
{
- // abort if statistics are not yet initialized
- if(stats[COINS_COLLECTED_STAT][SPLAYER] == -1) return;
+ // skip draw if level was never played
+ // TODO: do we need this?
+ if (coins == nv_coins) return;
+
+ // skip draw if stats were declared invalid
+ if (!valid) return;
// abort if we have no backdrop
if (!backdrop) return;
-
- int box_w = 130+130+130;
+
+ int box_w = 220+110+110;
int box_h = 30+20+20+20;
int box_x = (int)((SCREEN_WIDTH - box_w) / 2);
int box_y = (int)(SCREEN_HEIGHT / 2) - box_h;
int bd_y = box_y + (box_h / 2) - (bd_h / 2);
int col1_x = box_x;
- int col2_x = col1_x+130;
+ int col2_x = col1_x+200;
int col3_x = col2_x+130;
int row1_y = box_y;
int row3_y = row2_y+20;
int row4_y = row3_y+20;
+ context.push_transform();
+ context.set_alpha(0.5);
context.draw_surface(backdrop, Vector(bd_x, bd_y), LAYER_GUI);
+ context.pop_transform();
- char buf[129];
- context.draw_text(white_text, "You", Vector(col2_x, row1_y), LEFT_ALLIGN, LAYER_GUI);
- context.draw_text(white_text, "Best", Vector(col3_x, row1_y), LEFT_ALLIGN, LAYER_GUI);
-
- context.draw_text(white_text, "Coins", Vector(col1_x, row2_y), LEFT_ALLIGN, LAYER_GUI);
- snprintf(buf, 128, "%d/%d", stats[COINS_COLLECTED_STAT][SPLAYER], stats[COINS_COLLECTED_STAT][STOTAL]);
- context.draw_text(gold_text, buf, Vector(col2_x, row2_y), LEFT_ALLIGN, LAYER_GUI);
- if (best_stats && (best_stats->stats[COINS_COLLECTED_STAT][SPLAYER] > stats[COINS_COLLECTED_STAT][SPLAYER])) {
- snprintf(buf, 128, "%d/%d", best_stats->stats[COINS_COLLECTED_STAT][SPLAYER], best_stats->stats[COINS_COLLECTED_STAT][STOTAL]);
- }
- context.draw_text(gold_text, buf, Vector(col3_x, row2_y), LEFT_ALLIGN, LAYER_GUI);
-
- context.draw_text(white_text, "Time", Vector(col1_x, row3_y), LEFT_ALLIGN, LAYER_GUI);
- snprintf(buf, 128, "%d:%02d", stats[TIME_NEEDED_STAT][SPLAYER] / 60, stats[TIME_NEEDED_STAT][SPLAYER] % 60);
- context.draw_text(gold_text, buf, Vector(col2_x, row3_y), LEFT_ALLIGN, LAYER_GUI);
- if (best_stats && (best_stats->stats[TIME_NEEDED_STAT][SPLAYER] < stats[TIME_NEEDED_STAT][SPLAYER])) {
- snprintf(buf, 128, "%d:%02d", best_stats->stats[TIME_NEEDED_STAT][SPLAYER] / 60, best_stats->stats[TIME_NEEDED_STAT][SPLAYER] % 60);
- }
- context.draw_text(gold_text, buf, Vector(col3_x, row3_y), LEFT_ALLIGN, LAYER_GUI);
-
- context.draw_text(white_text, "Badguys", Vector(col1_x, row4_y), LEFT_ALLIGN, LAYER_GUI);
- snprintf(buf, 128, "%d/%d", stats[BADGUYS_KILLED_STAT][SPLAYER], stats[BADGUYS_KILLED_STAT][STOTAL]);
- context.draw_text(gold_text, buf, Vector(col2_x, row4_y), LEFT_ALLIGN, LAYER_GUI);
- if (best_stats && (best_stats->stats[BADGUYS_KILLED_STAT][SPLAYER] > stats[BADGUYS_KILLED_STAT][SPLAYER])) {
- snprintf(buf, 128, "%d/%d", best_stats->stats[BADGUYS_KILLED_STAT][SPLAYER], best_stats->stats[BADGUYS_KILLED_STAT][STOTAL]);
- }
- context.draw_text(gold_text, buf, Vector(col3_x, row4_y), LEFT_ALLIGN, LAYER_GUI);
-
+ context.draw_text(normal_font, _("You"), Vector(col2_x, row1_y), ALIGN_LEFT, LAYER_GUI, Statistics::header_color);
+ context.draw_text(normal_font, _("Best"), Vector(col3_x, row1_y), ALIGN_LEFT, LAYER_GUI, Statistics::header_color);
+
+ context.draw_text(normal_font, _("Coins"), Vector(col2_x-16, row3_y), ALIGN_RIGHT, LAYER_GUI, Statistics::header_color);
+ int coins_best = (best_stats && (best_stats->coins > coins)) ? best_stats->coins : coins;
+ int total_coins_best = (best_stats && (best_stats->total_coins > total_coins)) ? best_stats->total_coins : total_coins;
+ context.draw_text(normal_font, coins_to_string(coins, total_coins), Vector(col2_x, row3_y), ALIGN_LEFT, LAYER_GUI, Statistics::text_color);
+ context.draw_text(normal_font, coins_to_string(coins_best, total_coins_best), Vector(col3_x, row3_y), ALIGN_LEFT, LAYER_GUI, Statistics::text_color);
+
+ context.draw_text(normal_font, _("Secrets"), Vector(col2_x-16, row4_y), ALIGN_RIGHT, LAYER_GUI, Statistics::header_color);
+ int secrets_best = (best_stats && (best_stats->secrets > secrets)) ? best_stats->secrets : secrets;
+ int total_secrets_best = (best_stats && (best_stats->total_secrets > total_secrets)) ? best_stats->total_secrets : total_secrets;
+ context.draw_text(normal_font, secrets_to_string(secrets, total_secrets), Vector(col2_x, row4_y), ALIGN_LEFT, LAYER_GUI, Statistics::text_color);
+ context.draw_text(normal_font, secrets_to_string(secrets_best, total_secrets_best), Vector(col3_x, row4_y), ALIGN_LEFT, LAYER_GUI, Statistics::text_color);
+
+ context.draw_text(normal_font, _("Time"), Vector(col2_x-16, row2_y), ALIGN_RIGHT, LAYER_GUI, Statistics::header_color);
+ float time_best = (best_stats && (best_stats->time < time)) ? best_stats->time : time;
+ context.draw_text(normal_font, time_to_string(time), Vector(col2_x, row2_y), ALIGN_LEFT, LAYER_GUI, Statistics::text_color);
+ context.draw_text(normal_font, time_to_string(time_best), Vector(col3_x, row2_y), ALIGN_LEFT, LAYER_GUI, Statistics::text_color);
}
void
-Statistics::add_points(int stat, int points)
+Statistics::zero()
{
- stats[stat][SPLAYER] += points;
+ reset();
+ total_coins = 0;
+ total_badguys = 0;
+ total_secrets = 0;
}
-int
-Statistics::get_points(int stat)
+void
+Statistics::reset()
{
- return stats[stat][SPLAYER];
+ coins = 0;
+ badguys = 0;
+ time = 0;
+ secrets = 0;
}
void
-Statistics::set_points(int stat, int points)
+Statistics::merge(const Statistics& s2)
{
- stats[stat][SPLAYER] = points;
+ if (!s2.valid) return;
+ coins = std::max(coins, s2.coins);
+ total_coins = s2.total_coins;
+ badguys = std::max(badguys, s2.badguys);
+ total_badguys = s2.total_badguys;
+ time = std::min(time, s2.time);
+ secrets = std::max(secrets, s2.secrets);
+ total_secrets = s2.total_secrets;
}
void
-Statistics::set_total_points(int stat, int points)
+Statistics::operator+=(const Statistics& s2)
{
- stats[stat][STOTAL] = points;
+ if (!s2.valid) return;
+ if (s2.coins != nv_coins) coins += s2.coins;
+ if (s2.total_coins != nv_coins) total_coins += s2.total_coins;
+ if (s2.badguys != nv_badguys) badguys += s2.badguys;
+ if (s2.total_badguys != nv_badguys) total_badguys += s2.total_badguys;
+ if (s2.time != nv_time) time += s2.time;
+ if (s2.secrets != nv_secrets) secrets += s2.secrets;
+ if (s2.total_secrets != nv_secrets) total_secrets += s2.total_secrets;
}
void
-Statistics::reset()
+Statistics::declare_invalid()
{
- for(int i = 0; i < NUM_STATS; i++)
- stats[i][SPLAYER] = 0;
+ valid = false;
}
-void
-Statistics::merge(Statistics& stats_)
-{
-// stats[SCORE_STAT][SPLAYER] = std::max(stats[SCORE_STAT][SPLAYER], stats_.stats[SCORE_STAT][SPLAYER]);
- stats[COINS_COLLECTED_STAT][SPLAYER] = std::max(stats[COINS_COLLECTED_STAT][SPLAYER], stats_.stats[COINS_COLLECTED_STAT][SPLAYER]);
- stats[BADGUYS_KILLED_STAT][SPLAYER] =
- std::max(stats[BADGUYS_KILLED_STAT][SPLAYER], stats_.stats[BADGUYS_KILLED_STAT][SPLAYER]);
- stats[TIME_NEEDED_STAT][SPLAYER] =
- my_min(stats[TIME_NEEDED_STAT][SPLAYER], stats_.stats[TIME_NEEDED_STAT][SPLAYER]);
-
- stats[COINS_COLLECTED_STAT][STOTAL] = stats_.stats[COINS_COLLECTED_STAT][STOTAL];
- stats[BADGUYS_KILLED_STAT][STOTAL] = stats_.stats[BADGUYS_KILLED_STAT][STOTAL];
- stats[TIME_NEEDED_STAT][STOTAL] = stats_.stats[TIME_NEEDED_STAT][STOTAL];
+std::string
+Statistics::coins_to_string(int coins, int total_coins) {
+ std::ostringstream os;
+ os << std::min(coins, 999) << "/" << std::min(total_coins, 999);
+ return os.str();
}
-void
-Statistics::operator+=(const Statistics& stats_)
-{
- for(int i = 0; i < NUM_STATS; i++)
- {
- if(stats_.stats[i][SPLAYER] == -1)
- continue;
- stats[i][SPLAYER] += stats_.stats[i][SPLAYER];
- if(stats_.stats[i][STOTAL] != -1)
- stats[i][STOTAL] += stats_.stats[i][STOTAL];
- }
+std::string
+Statistics::frags_to_string(int badguys, int total_badguys) {
+ std::ostringstream os;
+ os << std::min(badguys, 999) << "/" << std::min(total_badguys, 999);
+ return os.str();
+}
+
+std::string
+Statistics::time_to_string(float time) {
+ int time_csecs = std::min(static_cast<int>(time * 100), 99 * 6000 + 9999);
+ int mins = (time_csecs / 6000);
+ int secs = (time_csecs % 6000) / 100;
+ int cscs = (time_csecs % 6000) % 100;
+
+ std::ostringstream os;
+ os << std::setw(2) << std::setfill('0') << mins << ":" << std::setw(2) << std::setfill('0') << secs << "." << std::setw(2) << std::setfill('0') << cscs;
+ return os.str();
}
+
+std::string
+Statistics::secrets_to_string(int secrets, int total_secrets) {
+ std::ostringstream os;
+ os << std::min(secrets, 999) << "/" << std::min(total_secrets, 999);
+ return os.str();
+}
+
projects / supertux.git / blobdiff