Third Pass: Geometry Separation and Reprojection

Image Set B

The next major issue involves excessive texture doubling from prominent areas of geometry onto other surfaces that are part of the same object. The image (below) shows the water tank and pipes on the left side of the arch on image set B, doubling onto the building facades and especially problematic between frames 30 and 70.

Experimentation established two ways that the doubling artefacts can be addressed, one being corrective and the other preventative. The corrective approach involves overpainting the affected areas of texture using the patch projection method. However initial tests on this particular image set indicated that several patches would be required over the 40 affected frames. This feels prohibitive in terms of time and effort.

The preventative approach calls on previous work where I have established that, by separating these geometric elements from the main body of the building and projecting the textures of just these elements with new shaders, the problem is eradicated. This would effectively become a separate layered projection just for these elements using the same projection cameras (0 and 50) as the main building.

Image Set C

This set also presented major doubling issues from the stone pillars, streetlamps and railings, doubling onto the structures behind.

Initial testing found that multiple patch projections would be needed to correct this, especially on the leftmost building in the set, and the decision was taken to split the pillars/lamps from the main geometric structure and project them separately using their own layered projection system.

The image below shows the elements separated from the main geometric structure projected using temporary shaders

Image Set D

There are major doubling issues on building 6 (left), most evident in the bollards and chains, the ornamental orbs on the staircase and the nearmost corner tower structure.

Initial testing found that multiple patch projections would be needed to correct this, especially on the leftmost building in the set. However this can be avoided by implementing a similar approach to that used on image set C; separating this geometry from the main structure and projecting separately.

Other than the aforementioned resolution loss, there are no doubling or smearing artefacts apparent on building 7 (right).

Given that these elements were part of the same image set when the first pass resolution tests were undertaken, the same projection cameras as those used to project the main building can be deployed. 

This method proved to be so effective, that the same approach was used to separate and reproject other problematic geometric elements, in particular the tower on the front corner of the leftmost building on image set D, which is creating similar doubling issues when part of the same shader network as the main building.

The image below shows the elements separated from the main geometric structure projected using temporary shaders.

As there is overlap between the patio elements and the protruding structures, these could not use the same shader setup so would need separate networks.