Cg is a high-level shading language developed by Nvidia.
Questions tagged [cg]
300 questions
0
votes
1 answer
Get the vertex_id variable in a NVIDIA CG vertex shader to create Index Map
I need to generate an Index Map (Index list) containing the id of each projected vertex. My shader code is based on NVIDIA CG 3.0 and I can't find in the documentation the build-in variable name to extract the id of each vertex.
In GLSL is something…
tat0
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0
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1 answer
Default parameter values via semantics in GLSL
I know little to nothing about the actual writing of shaders although I have a basic understanding of their place in the rendering pipeline. I have a CG shader that I have aquired from here and here. I am attempting to convert these shaders to…
Mako_Energy
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Can a distortion matrix be a combination of a rotation and a scale?
Consider the following transformation matrix for distortion in a 2D space.
[1 a 0]
M=[b 1 0]
[0 0 1]
Is it possible to obtain the same transformation by combinating a rotation and a scale?
andrepcg
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Shader of pressure card
I need to write a shader of pressure map. Similar to the following:
Card
It is necessary to provide closed lines with borders, which shows tonality of pressure and the corresponding color gradation areas with different pressures. Maybe in future it…
user2391797
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SkyBox texture not showing (NVIDIA CG)
This is my Box.cpp code:
using namespace std;
#include
#include "Box.h"
void MyErrorCallback(void)
{
const char* errorString = cgGetErrorString(cgGetError());
printf("Cg error: %s", errorString);
}
Box::Box(CGcontext cgContext,…
Itzik984
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0
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1 answer
Cg: omit depth write
I am outputting depth in Cg in a branch, like so:
ZWrite On
..
void frag(v2f IN, out color : COLOR, out depth : DEPTH) {
if (statement) {
color = float4(1);
} else {
color = float4(0);
depth = 0;
}
}
However as you see I omit writing the…
RobotRock
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0
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Random value in nVidia CG language shader (Unity)
I'm diving into CG shaders. I'm baking a vertex shader that needs one random constant (computed just once at start time). I know that in Unity it's pretty easy to pass a value from a script to the shader, but I'd like to know if there is any way to…
Steak Overflow
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1 answer
Encoding data in an 8-bit float (cg)
The language is cg.
I have an 8-bit float that must be between 0 and 1 (it's the 'a' component of a float4 rgba color value). I want to store a 6-bit unsigned integer and a 2-bit unsigned integer in that. How can I safely store these two values in…
lifeformed
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CG shader threshold function
Is there some builtin fragment function in CG that allows me to compute the following without conditionals?
y = x>bias?1.0f:0.0f;
matthias_buehlmann
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shader - CG/GLSL/HLSL how to implement jittering
In computer graphics it's a common technique to apply jittering to sampling positions in order to avoid visible sampling patterns.
What's the proper way to apply jittering to sampl-positions in a fragment shader? One way I could think of would be to…
matthias_buehlmann
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0
votes
1 answer
CG runtime linker error with cmake project (g++)
I'm getting these linker errors:
/usr/bin/ld: cannot find -lCg
/usr/bin/ld: cannot find -lCgGL
I'm using the FindCg.cmake frome here: http://code.google.com/p/nvidia-texture-tools/source/browse/branches/2.0/cmake/FindCg.cmake?r=452
Then adding the…
bitgregor
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1 answer
Ogre3d / Compositor related issue
I killed my whole day trying to figure out, why the code below is not working:
I have this .compositor script:
compositor BW
{
technique
{
texture rt0 target_width target_height PF_A8R8G8B8
target rt0
{
…
Anon
- 1,274
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0
votes
1 answer
Non-constant index into uniform array CG Shader
According to this nVidia CG tutorial (and my own experience) accessing uniform arrays in CG shaders with a non-constant index is either inefficient or unsupported (more often than not, unsupported it seems).
My question is; how can I circumvent this…
DAVco
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0
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2 answers
CG to GLSL: f3texRECT equivalent?
I'm trying to convert a CG program to a GLSL program.
What I've done so far seems correct, but the GLSL shader outputs an incorrect output. The incorrect behavior is defined by a set of test images.
The only dark point on which I'm investigating is…
Luca
- 11,646
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0
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1 answer
3D model rendering and shaders
I have a 3D model and while rendering i am using shaders to calculate the vertex color(computationally intensive task), based on some parameters. These parameters change with time. So basically i need to calculate the vertex color based on the…
rps
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