Setting a timer vertexshader constant?

[cooljayman]

Im trying to set a Timer value as a vertexShader Constant, OnSetConstants:

Code: Select all

u32 currtime = device->getTimer()->getTime();

	   services->setVertexShaderConstant("Timer", reinterpret_cast<f32*>(&currtime), 1);

But the time going into the shader is not getting updated? What am I doing wrong?

[FuzzYspo0N]

My guess is you are passing a u32 into a f32 variable. this is quite interesting becuase a had this problem recently using animations where if i cast it to f32 and it was outside of the environment, it didnt get changed at all, because it kept getting truncated to 0

dont cast variables to and from without casting it before properly

[arras]

I did have similar problems and it was also caused by casting.

[Halifax]

Well this is just a simple problem of how you are casting. Here is what you are saying with this:

Code: Select all

reinterpret_cast<f32*>(&currtime)

Reference my pointer, then cast the u32* to an f32* so that it is instead accessed by 9 bytes (I forget how big floats are) instead of 4 bytes. When you cast between pointers it just changes the way in which they are accessed for when you do 'pointer++' etc. So casting u32* to u8* would mean that 'pointer++' would increment through the value 1 byte at a time instead of 4 bytes. So to correct this, you just need to change the order of operations:

Code: Select all

tempFloat = (f32)currtime;
... use &tempFloat ...