Tipoun

08-10-2011, 01:40 AM

Hello everybody,

I'm new in OpenGL programming, and I have a problem.

I have a scene whith one model. My model appears correct but lighting not. When I turn around it, the light moves too, and causes bad results.

I create a camera class, I think it's ok because I can turn around my model correctly:

class Camera

{

public:

Camera()

: _yaw(0), _pitch(0), _roll(0)

{

}

Matrix4x4f getMatrix() const

{

Vector3f up = _rotation.rotatedVector(Vector3f(0, 1, 0)); // up vector

Vector3f target = _rotation.rotatedVector(Vector3f(0, 0, -1)) + _position; // forward vector

Matrix4x4f viewMatrix;

viewMatrix.lookAt(_position, target, up);

return viewMatrix;

}

void move(Vector3f distance)

{

_position += _rotation.rotatedVector(distance);

}

void rotate(float yaw, float pitch, float roll = 0)

{

_yaw += yaw;

_pitch += pitch;

_roll += roll;

Quaternionf y = Quaternionf::fromAxisAndAngle(Vector3f(0, 1, 0), _yaw);

Quaternionf p = Quaternionf::fromAxisAndAngle(Vector3f(1, 0, 0), _pitch);

Quaternionf r = Quaternionf::fromAxisAndAngle(Vector3f(0, 0, 1), _roll);

_rotation = y * p * r;

}

Vector4f position() const

{

return Vector4f(_position.x(), _position.y(), _position.z());

}

void setPosition(const Vector3f &pos)

{

_position = pos;

}

private:

Vector3f _position;

Quaternionf _rotation;

float _yaw, _pitch, _roll;

float _fov, _near, _far;

};

Then I have a function that sets uniforms:

glUseProgram(_programID);

Matrix4x4f camMatrix = scene->activeCamera().getMatrix();

Matrix4x4f mvMatrix = camMatrix * object->modelMatrix();

glUniformMatrix4fv(mvMatrixUniformLocation, 1, GL_FALSE, mvMatrix);

glUniformMatrix4fv(mvpMatrixUniformLocation, 1, GL_FALSE, scene->projectionMatrix() * mvMatrix);

glUniformMatrix3fv(normalMatrixUniformLocation, 1, GL_FALSE, mvMatrix.normalMatrix());

glUniform4fv(diffuseUniformLocation, 1, object->model()->diffuse());

//glUniform4fv(l0PosUniformLocation, 1, (mvMatrix * scene->light().position()));

For the last line, when I want to send light position do I need to convert it in model view transformation ?

Finally my shaders:

#version 150

// Per vertex

in vec4 in_Vertex;

in vec3 in_Normal;

in vec2 in_TexCoord;

// Per batch

uniform mat4 mvMatrix;

uniform mat4 mvpMatrix;

uniform mat3 normalMatrix;

// To fragment program

smooth out vec3 vEyeNormal;

smooth out vec3 vEyeVec;

smooth out vec4 vEyeLightDir;

void main(void)

{

gl_Position = mvpMatrix * in_Vertex;

vEyeNormal = (normalMatrix * in_Normal).xyz;

vec3 vVertex = (mvMatrix * in_Vertex).xyz;

vEyeLightDir = vec4(10.0, 0.0, 0.0, 1.0) - vVertex; // light position in hard

vEyeVec = -vVertex;

}

#version 150

// From vertex program

smooth in vec3 vEyeNormal;

smooth in vec3 vEyeVec;

smooth in vec4 vEyeLightDir;

// Per batch

uniform mat4 mvMatrix;

uniform mat4 mvpMatrix;

uniform mat3 normalMatrix;

vec4 diffuse;

// Final color

out vec4 out_Color;

void main(void)

{

vec3 N = normalize(vEyeNormal);

vec3 L = normalize(vEyeLightDir);

float NdotL = max(0.0, dot(L, N));

out_Color = vec4(diffuse.xyz * NdotL, 1.0);

}

So I don't understand why my lighting moves when I rotate my camera.

Can you help me ?

Thanks a lot

Tipoun

I'm new in OpenGL programming, and I have a problem.

I have a scene whith one model. My model appears correct but lighting not. When I turn around it, the light moves too, and causes bad results.

I create a camera class, I think it's ok because I can turn around my model correctly:

class Camera

{

public:

Camera()

: _yaw(0), _pitch(0), _roll(0)

{

}

Matrix4x4f getMatrix() const

{

Vector3f up = _rotation.rotatedVector(Vector3f(0, 1, 0)); // up vector

Vector3f target = _rotation.rotatedVector(Vector3f(0, 0, -1)) + _position; // forward vector

Matrix4x4f viewMatrix;

viewMatrix.lookAt(_position, target, up);

return viewMatrix;

}

void move(Vector3f distance)

{

_position += _rotation.rotatedVector(distance);

}

void rotate(float yaw, float pitch, float roll = 0)

{

_yaw += yaw;

_pitch += pitch;

_roll += roll;

Quaternionf y = Quaternionf::fromAxisAndAngle(Vector3f(0, 1, 0), _yaw);

Quaternionf p = Quaternionf::fromAxisAndAngle(Vector3f(1, 0, 0), _pitch);

Quaternionf r = Quaternionf::fromAxisAndAngle(Vector3f(0, 0, 1), _roll);

_rotation = y * p * r;

}

Vector4f position() const

{

return Vector4f(_position.x(), _position.y(), _position.z());

}

void setPosition(const Vector3f &pos)

{

_position = pos;

}

private:

Vector3f _position;

Quaternionf _rotation;

float _yaw, _pitch, _roll;

float _fov, _near, _far;

};

Then I have a function that sets uniforms:

glUseProgram(_programID);

Matrix4x4f camMatrix = scene->activeCamera().getMatrix();

Matrix4x4f mvMatrix = camMatrix * object->modelMatrix();

glUniformMatrix4fv(mvMatrixUniformLocation, 1, GL_FALSE, mvMatrix);

glUniformMatrix4fv(mvpMatrixUniformLocation, 1, GL_FALSE, scene->projectionMatrix() * mvMatrix);

glUniformMatrix3fv(normalMatrixUniformLocation, 1, GL_FALSE, mvMatrix.normalMatrix());

glUniform4fv(diffuseUniformLocation, 1, object->model()->diffuse());

//glUniform4fv(l0PosUniformLocation, 1, (mvMatrix * scene->light().position()));

For the last line, when I want to send light position do I need to convert it in model view transformation ?

Finally my shaders:

#version 150

// Per vertex

in vec4 in_Vertex;

in vec3 in_Normal;

in vec2 in_TexCoord;

// Per batch

uniform mat4 mvMatrix;

uniform mat4 mvpMatrix;

uniform mat3 normalMatrix;

// To fragment program

smooth out vec3 vEyeNormal;

smooth out vec3 vEyeVec;

smooth out vec4 vEyeLightDir;

void main(void)

{

gl_Position = mvpMatrix * in_Vertex;

vEyeNormal = (normalMatrix * in_Normal).xyz;

vec3 vVertex = (mvMatrix * in_Vertex).xyz;

vEyeLightDir = vec4(10.0, 0.0, 0.0, 1.0) - vVertex; // light position in hard

vEyeVec = -vVertex;

}

#version 150

// From vertex program

smooth in vec3 vEyeNormal;

smooth in vec3 vEyeVec;

smooth in vec4 vEyeLightDir;

// Per batch

uniform mat4 mvMatrix;

uniform mat4 mvpMatrix;

uniform mat3 normalMatrix;

vec4 diffuse;

// Final color

out vec4 out_Color;

void main(void)

{

vec3 N = normalize(vEyeNormal);

vec3 L = normalize(vEyeLightDir);

float NdotL = max(0.0, dot(L, N));

out_Color = vec4(diffuse.xyz * NdotL, 1.0);

}

So I don't understand why my lighting moves when I rotate my camera.

Can you help me ?

Thanks a lot

Tipoun