On 07.06.2009 22:22, Henri Verbeet wrote:
Even if the format isn't lockable, you can still use the data with a shader.
If it's a typical depth format the shader will see normalized values.
Information on DF16 seems to be sparse, one thing I found was: http://discussms.hosting.lsoft.com/SCRIPTS/WA-MSD.EXE?A2=ind0611A&L=DIRE... It says that DF16 returns "real" depth values - which would indeed be normalized.
Typically float formats aren't normalized, so you can have values outside the traditional [0.0,1.0] range. If there's no specific extension for this format you could use GL_DEPTH_COMPONENT32F as internal format and GL_HALF_FLOAT_ARB as type, although that would waste some memory, of course.
On what graphics cards is that extension supported? DF16 is supported since the R300. It appears that float depth formats are much younger, so it seems unlikely DF16 is actually a float format internally. Does D3D(9) allow a depth range outside [0.0,1.0] anyway?
Is there any specific application that needs this format?
Some ATI graphics demos (e.g. Toy Shop). Probably at least some games that use shadow mapping.
-f.r.