Velvet Assassin For Mac

 



I just got news that Vel­vet Assas­sin has been port­ed over to the Mac and is avail­able on the App Store! How­ev­er, I was not at all involved in the Mac port and I don’t know the devel­op­ers who did—it came as a sur­prise to me as to any­one else in the for­mer team. Here is a direct iTunes link: http://itunes.apple.com/app/id586878367.

Velvet Assassin is a stealth video game for Microsoft Windows and Xbox 360, released in 2009. Velvet Assassin's working title was Sabotage. It was released on the Mac app store in 2013. Overview Violette sneaking up on an unaware soldier. Velvet Assassin is a third-person stealth action game developed by Replay and published by SouthPeak for the Xbox 360 and PC on April 30, 2009. The Steam version later supported Mac platforms on January 19, 2013. Set in World War II, players control British secret agent Violette Summer (loosely based on real-life World War II spy Violette. Velvet Assassin now on the Mac App Store! Buy it Now: Inspired by the fascinating story and unbreakable spirit of British secret agen.

Velvet Assassin For Mac Torrent

Shader Bug on ATI graphic cards

Unfor­tu­nate­ly there is a shad­er bug with ATI graph­ics chips. It hap­pened to me while try­ing it out on a 2011 iMac with an ATI Radeon HD 5670. I got reports from friends that this is not a prob­lem of the Mac port itself but it hap­pens on PC too. The prob­lem is relat­ed to ATI chips with dri­vers that are new­er than 2010 or so. Here is a screen­shot:

Velvet assassin fix

The bug appears as low frame rate and with the main char­ac­ter shad­ed sol­id black, except for eyes and attach­ments. This hints at a numer­i­cal float­ing-point prob­lem con­nect­ed to soft-skin­ning. And indeed, I was able to track down the cul­prit and there are two things hap­pen­ing:

  • There is a square-root oper­a­tion in the ver­tex shad­er that gen­er­ates NaN, but only when soft-skin­ning is enabled. This is respon­si­ble for the black shad­ing on the char­ac­ters.
  • The low frame rate is relat­ed to the address reg­is­ter indi­rec­tion used for soft-skin­ning. The dri­ver is some­how mis-com­pil­ing this code, since the per­for­mance returns to nor­mal when this part is com­ment­ed out (but then, of course, the char­ac­ters are not ani­mat­ed). There is not much that can be done about this with­out a fix from ATI.
Mac

Patch

I have made a patch to at least fix the visu­al appear­ance, so the char­ac­ters are no longer black. Unzip the patch and replace the two shad­er files in the Vel­vet Assas­sin data fold­er. On the Mac, this is locat­ed inside the app pack­age, exact­ly here:

Down­load the patch:

As a side effect, you’ll now get to see all the things that I did not have room to write about in the ShaderX book. For all of those who are going to dis­sect the shad­er code, you’ll find the fol­low­ing fea­tures in there:

  • Algo­rith­mic anti-alias­ing of spec­u­lar high­lights (and envi­ron­ment maps too), when high qual­i­ty is select­ed. It is done via a heuris­tic that low­ers the mate­r­i­al glossi­ness depen­dent on the ddx/ddy of the nor­mal, so both nor­mal-map per­tu­ba­tion and fine geom­e­try is tak­en into account.
  • Envi­ron­ment maps are inte­grat­ed in the shad­ing mod­el, with auto­mat­ic selec­tion of a mip lev­el that cor­re­sponds to the size of spec­u­lar high­light.
  • Two modes of alpha-trans­paren­cy: One mode to be used as a trans­par­ent but sol­id sur­face (like glass), then the spec­u­lar reflec­tion is not mod­i­fied by the alpha val­ue; and anoth­er mode for alpha as a cov­er­age val­ue (for instance when fad­ing-out strands of hair) so the spec­u­lar reflec­tion must be atten­u­at­ed too.
  • Lots of gam­ma/de-gam­ma mag­ic.

Velvet Assassin For Mac Osx

Enjoy!