In July 2012, Final Fantasy Versus XIII was cancelled and reshaped into Final Fantasy XV. Hajime Tabata was placed in charge of the game and event director Hiroki Chiba was brought in to help Jun Akiyama remake the scene events in Luminous Studio.
Due to the game being remade in this new engine, all of Akiyama's event scenes using Crystal Tools when the game was called Final Fantasy Versus XIII were scrapped. Akiyama has since left the project, with Chiba taking over as the event director.
Final Fantasy XV uses Square Enix's Luminous Studio game engine. There are about 5 million polygons per frame with each character made up of at max 100,000 polygons.
The inner hair alone has 20,000 polygons, which is 5 times the previous generation.
Character models have around 600 bones, roughly 10-12 times greater than what was seen previous generation.
About 150 bones are for the face, 300 for hair and clothes, and 150 for the body.
There is a bone-based physical simulation technology applied so that clothing reacts to the body's movements.
The capacity of just one character's textures is about 30 megabytes. The team are using 2048 x 2048 texels and 4096 x 4096 texels for HD textures.
The game's resolution is 1920 x 1080 pixels (1080p), with a target of 30fps frame rate.
The modernistic art direction of Final Fantasy XV derives inspiration from real world locations, as opposed to the more fantasy-futuristic feel of Final Fantasy VIII and the main characters' clothes are designed by the clothing store Roen rather than being designed by Tetsuya Nomura.
In its strive for a more corporeal-looking world, the style is somewhat reminiscent of Final Fantasy VIII, although darker and more monochromatic.
While the beginning of the game takes place in a more contemporary setting, as the story progresses the player will find various fantasy environments and atmospheres similar to what past titles like Final Fantasy VII did.
With the improved processing power of the PlayStation 4 and X-Box One, the need for pre-rendered cutscenes than many of its main series predecessors.
Former director Tetsuya Nomura has commented that even in considerably dynamic scenes, the player will be in control of their character, and cited the scene where Leviathan is rioting through the city as an example.
One of the concepts of the game's graphic design is to keep the original monster designs by Yoshitaka Amano from the previous titles and to adapt them in a realistic way.
However, director Hajime Tabata has mentioned that in creating a new game, throwing in familiar elements just to please the fans gives an impression of shallowness.
Thus, Tabata thinks carefully how Final Fantasy icons apply to the setting and ensures they are included there because they are necessary.

During Final Fantasy XV's development Square Enix shows off 2 scan shots of the (PSS) Pre-integrated Skin Shading.
The second pair shows off the effect of pre-integrated skin shading, an advanced technique for rendering realistic skin in games. It was made by Eric Penner by using Siggraph which stands for Special Interest Group on GRAPhics and Interactive Techniques it's the name for annual computer graphics (CG) convened by the ACM SIGGRAPH organization.
The team of Square Enix is pulling out all the stops to make the alleged (and yet confirmed) successor of old Cid looking sexy.
The first pair of the screenshots showcases the difference between Cidney with a pre-rendered cutscene (on the left), and rendered in real-time (on the right), thanks to Luminous Studio engine.
Thanks to Twitter users Cadet and Ouji Night for sharing it.

New screenshots of Cidney in Final Fantasy XV.
The first screenshot showcases Cidney's beautiful eyes, showing how they have been modeled reproducting the structure of a real eye, allowing for realistic reflections, including those from the peripheral area.
The second pair of screenshots compares the eye model without (left) and with (right) the advanced eye shader.

The third picture showcases the advanced hair effects on Luna, the wig used as a model, and a performance capture session.
The hair is about 20,000-30,000 polygons per character, and Square Enix used the Light Scattering from Human Hair Fibers model by Stephen R. Marschner in order to retain a natural glossy look of the fibers and the way they reflect the light, Luna's hairstyle was created by a professional hair stylist.