formZ SDK | 4.0 Call Back Reference | RenderZone Shader
FZ_SHDR_CBAK_TRNS_FSET_TYPE
formZ transparency shader callbacks function set id.
FZ_SHDR_CBAK_TRNS_FSET_NAME
formZ transparency shader callbacks function set name.
FZ_SHDR_CBAK_TRNS_FSET_VERSION
formZ transparency shader callbacks function set version.
Description
Function set for transparency shaders. The functions in this set need to
be supplied by the plugin or script to implement a transparency shader.
The main shader function is the fz_shdr_cbak_trns_pixel callback. It is expected
to compute the transparency of a surface pixel. Depending
on whether the shader is a 2d or 3d shader, the 2d texture
space coordinate (s,t) or the 3d texture space coordinate (x,y,z)
relating to the pixel should be taken as the basis of the transparency
computation. These coordinate values can be retrieved with the functions
(2d) or fz_shdr_get_tspace_pnt (3d). The pixel
transparency may also be computed from other surface information,
such as the surface normal, which is the case in the formZ
Neon transparency shader. If the fz_shdr_cbak_trns_pixel function returns 0.0
the pixel is considered completely opaque. If the fz_shdr_cbak_trns_pixel function
returns 1.0 the pixel is considered completely transparent and
therefore invisible. Values less than 0.0 and greater than
1.0 are not accepted and will be clamped to 0.0 or 1.0.
There are required and optional functions. The required functions
are :
fz_shdr_cbak_trns_name
fz_shdr_cbak_trns_pixel
All other functions are optional, but must be supplied to
enable a certain functionality. For example, if the transparency
shader has any parameters, the fz_shdr_cbak_trns_set_parameters function must be supplied.
It is also advisable to implement a fz_shdr_cbak_trns_pre_render function, if
the fz_shdr_cbak_trns_pixel function uses information which can be calculated
once and does not change during the course of a rendering.
It is important to note, that the fz_shdr_cbak_trns_pixel function is called
at least once for each pixel, potentially thousands of times
during a single rendering. The faster the fz_shdr_cbak_trns_pixel function, the faster
the rendering will be.
Availability
5.0.0.0
Functions:
fz_shdr_cbak_trns_set_parameters
Defined in