Contents
When to use geometry shader?
Introduced as an extra stage between vertex processing and fragment processing, the geometry shader adds or deletes some elements in the geometry stream sent to the rendering pipeline.
What is a domain shader?
A domain shader is the third of three stages that work together to implement tessellation. The domain shader generates the surface geometry from the transformed control points from a hull shader and the UV coordinates. A domain shader is invoked once for each point generated by the fixed function tessellator.
What is Pixel Shader 3.0 on graphics cards?
A pixel shader is a software program that is used when processing graphics and it computes color and other graphic attributes of a pixel. It is possible to identify the pixel shader version of the graphics card installed on a computer system. .
How to render terrain based on heightmap shader?
This simple example will render a terrain based on a heightmap. Instead of building a mesh based on the heightmap, the mesh itself is just a regular grid and the heightmap is applied in the vertex shader. The full example can be found in HeightmapShader.escript.
What should the grid size be for terrain rendering?
Because the outer perimeter of each level must lie on the grid of the next-coarser level (as shown in Figure 2-4), the grid size n must be odd. Hardware may be optimized for texture sizes that are powers of 2, so we choose n = 2 k -1 (that is, 1 less than a power of 2) leaving 1 row and 1 column of the textures unused.
How is terrain rendered in geometry clipmap framework?
The geometry clipmap framework (Losasso and Hoppe 2004) treats the terrain as a 2D elevation image, prefiltering it into a mipmap pyramid of L levels as illustrated in Figure 2-1. For complex terrains, the full pyramid is too large to fit in memory.
How are level of detail techniques used in terrain rendering?
Numerous level-of-detail techniques have been developed to adapt the triangulation of the terrain mesh as a function of the view. However, most such techniques involve runtime creation and modification of mesh structures (vertex and index buffers), which can prove expensive on current graphics architectures.