Hi,

sorry to ask another question on shadow mapping but i’d like to know if i’m doing all correctly (because nothing goes right).

I’m following this tutorial:

Ampoff

The shader code is this:

```
[VERTEX SHADER]
uniform mat4 tmatrix;
varying vec4 projCoord;
void main()
{
vec3 lightVect, trueNormal;
vec4 realPos = gl_ModelViewMatrix * gl_Vertex;
lightVect = normalize(gl_LightSource[0].position.xyz - realPos.xyz);
trueNormal = gl_NormalMatrix * gl_Normal;
projCoord = tmatrix * realPos;
gl_FrontColor = vec4(dot(lightVect, trueNormal) - 0.1);
gl_TexCoord[0] = gl_MultiTexCoord0;
gl_Position = ftransform();
}
[FRAGMENT SHADER]
uniform sampler2D shadowMap;
uniform sampler2D lightTex;
varying vec4 projCoord;
const vec4 ambient = vec4(0.13), boost = vec4(1.06);
void main()
{
vec3 projectiveBiased = (projCoord.xyz / projCoord.q);
projectiveBiased = (projectiveBiased + 1.0) * 0.5;
vec4 shadowValue = texture2D(shadowMap, projectiveBiased.xy);
// vec4 lightValue = texture2D(lightTex, projectiveBiased.xy);
//if(shadowValue.z < projectiveBiased.z)
// gl_FragColor = ambient;
//else
// gl_FragColor = boost * gl_Color * lightValue + ambient;
if(shadowValue.z < projectiveBiased.z)
gl_FragColor = vec4(0.3,0.3,0.3,1.0);
else
gl_FragColor = vec4(1.0,1.0,1.0,1.0);
}
```

OK, this is what i’m doing:

- i take depth values from light view putting that in a depth texture;
- i calculate tmatrix in this way:

```
glPushMatrix();
glLoadIdentity();
glMultMatrix(lightProjectionMatrix);
glMultMatrix(lightViewMatrix);
glMultMatrix(InvCameraViewMatrix);
textureMatrix = glGet(GL_MODELVIEW_MATRIX);
glPopMatrix();
```

- i pass tmatrix and depth texture to shader and draw the scene.

Results are wrong, and when i move camera it seems that texture coordinates are not correctly calculated.

Am i doing something wrong?

Thank you very much.