Its a different texture. I worked myself with Carbon. There are different textiles with various knittings available. Like the patterns on knit-wear.
The reason has all something to do with stability. The usage in the Porsches interieur is purly optical. They take the original parts, glue the Fiber on top and coat it. For sure, some knittings are easier to bend then others, so on round curvy party they are easier to glue on the original parts than the others.
If we are looking to pure Carbon Fiber Parts (like you see in the GT or the Seats on the above picture) there you take a negative for and layer the Carbon Fibre inside. Based on the direction you put the textile you can influence the stability. Normally you have at least 2 layers which are running cross to each other (from the direction). High stability parts can easily come up to 6 or more layers. Sometimes with combination of other materials like honey-comb structures again for stability.
One to mention technique is been used in the McLaren SLR. Here the carbon fibre is knitted directly in the form of the car. Some front parts are - like a sock - knitted from ground off. This is - IMO - the future of car building.
let me know if you have any questions, as said, I started to work with this material 5 years ago. Its an interesting area (purly hobby... but thought many times to make a job out of that).
L@rs