Amount of Quake in Half Life 2

[daemonicky]

I know, that Half Life is cpp version of Quake, plus some variations (I do not know these). Someone said, that Half Life 2 is pretty much Quake (or Half Life) with some third party additions - like graphics (shaders, big textures, ...), physics (havok) ... Is it a big overstatement? Does somebody know how much Half Life 2 and Quake differ?
Thanks.

[ooppee]

Differs in many fashions. Has all the extra texture formats, sound engine features (surround sound for one), normal mapping, gloss textures ect. There's so much to list.

I know just from models:
-skeletal animation instead of vertex
-weighed skeleton (requires above)
-animation blending (having lower/upper body animate independantly)
-hitboxes assigned to areas on the skeleton - allowing more "realistic" damage options.
-"Merging" 2 models through the skeleton (like the p_models with the player model)
-Movement groups (talking mouths) that are independent of animation.
-Assigning a sound to execute on a animation without need of source code editing.
-Ragdolls
-Normal map textures
-Gloss textures
-Various support for different texture formats
-Alpha Channel support (not that "this color is invisible" thing)
-32bit textures over 8bit
-MUCH larger texture support and polycount support.

Those are just things in models I can think of right away.

[Spike]

the original half-life had 70% of those features too.

Quake3 is basically just Quake2 but with a few shader effects, for example, and 3rd party libs like jpg support.

Doom3 is basically just Quake3 but with a physics engine and no lights... err... sorry, realtime lights.

as with all things, you can have features out of your ears, but the important thing is how they all combine to provide a complete game. Each individual feature is simple, and many of those features you don't even realise could be listed as a feature. Its generally only the graphical ones that people will ever mention.