Home
Blogs
Forums
News
Portfolios
Projects
Tutorials
19 users logged in
New? Learn about game development.
Before posting, review our community guidelines.
Follow Us
Chat in the GameDev.net Discord!
Mastodon
Back to Graphics and GPU Programming

point light shadowing problem

Started by
1 comment, last by Asem 14 years, 3 months ago
I've looked over the net and found info on this but some of it is not clear. I have my FBO set up like this. Bind a CubeMap Texture Tell it to clamp to edge for s,t,r format the cubemap with GL_DEPTH_COMPONENT32f with no pixel data since I'll be reading to it from the framebuffer. Set FBO to use a GL_DEPTH_ATTACHMENT Set a renderbuffer for the depth buffer ------------- Bind FBO set draw back buffer to none clear the depth buffer for x, -x, y, -y, z, -z { attachTexToFBO(+x + i);//It's the glFrameBufferRenderTexture something like that set view to the pointlights position... (I'm kinda confused here) --I use a lookat matrix to try to do this. --I handle all the matrix math since I'm using opengl3.2 core render objects } unbind FBO use shadowshader render objects stop shadowshader -------------- 

void RenderFBO()
{


    static float dt = 0.0f;

    if( runTime )
        dt += 0.1f;

glMatrixMode( GL_PROJECTION );
glLoadIdentity();
gluPerspective(90.0, 1.333, 0.1, 100.0);
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();

matrix_math::Mat4X4<float> cameraDirection[6];
for(int i=0; i<6; i++)
    cameraDirection.identityClear();

///Setup Views
/*
//-Z, Z
cameraDirection[5] = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]) * matrix_math::MatrixRotationRoll(0.0f) * matrix_math::MatrixRotationYaw(0.0f) * matrix_math::MatrixRotationPitch(0.0f);
cameraDirection[4] = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]) * matrix_math::MatrixRotationRoll(0.0f) * matrix_math::MatrixRotationYaw(0.0f) * matrix_math::MatrixRotationPitch(-180.0f);

//-Y, Y
cameraDirection[3] = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]) * matrix_math::MatrixRotationRoll(180.0f) * matrix_math::MatrixRotationYaw(0.0f) * matrix_math::MatrixRotationPitch(-90.0f);
cameraDirection[2] = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]) * matrix_math::MatrixRotationRoll(0.0f) * matrix_math::MatrixRotationYaw(0.0f) * matrix_math::MatrixRotationPitch(-90.0f);

//-X, X
cameraDirection[1] = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]) * matrix_math::MatrixRotationRoll(-90.0f) * matrix_math::MatrixRotationYaw(0.0f) * matrix_math::MatrixRotationPitch(-90.0f);
cameraDirection[0] = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]) * matrix_math::MatrixRotationRoll(90.0f) * matrix_math::MatrixRotationYaw(0.0f) * matrix_math::MatrixRotationPitch(-90.0f);
*/
///Setup Projection
matrix_math::Mat4X4<float> world;
matrix_math::Mat4X4<float> viewMatrix;
projection = matrix_math::PerspectiveMatrix<float>(90.0f, float(Width)/float(Height), 0.1f, 100.0f);

/////////////
//-Z, +Z
cameraDirection[5] = matrix_math::LookAtMatrix(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2], 4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]-1.0f, -1.0f, 0.0f, 0.0f);
cameraDirection[4] = matrix_math::LookAtMatrix(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2], 4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]+0.0f,  1.0f, 0.0f, 0.0f);

//-Y, Y
cameraDirection[3] = matrix_math::LookAtMatrix(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2], 4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f)-1.0f, movementL[2], 0.0f, 0.0f, -1.0f);//okay -
cameraDirection[2] = matrix_math::LookAtMatrix(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2], 4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f)+1.0f, movementL[2], 0.0f, 0.0f,  1.0f);//okay +

//-X, +X
cameraDirection[1] = matrix_math::LookAtMatrix(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2], 4.0f*cos(dt*0.5f)-1.0f, 4.0f*sin(dt*0.5f), movementL[2], 0.0f, -1.0f, 0.0f);//okay -
cameraDirection[0] = matrix_math::LookAtMatrix(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2], -4.0f*cos(dt*0.5f)+1.0f, 4.0f*sin(dt*0.5f), -movementL[2], 1.0f,  0.0f, 0.0f);//okay +

///

    vector_math::Vec3<float> lightPosition = vector_math::Vec3<float>(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]);
    glProgramUniform3fvEXT( depthShader->GetHandle(), glGetUniformLocation(depthShader->GetHandle(), "lightPosition"), 1, lightPosition.getXYZ() );



glClear(GL_DEPTH_BUFFER_BIT);	
///PROBLEM HERE I DONT THINK THE CUBEMAP IS BEING FILLED RIGHT
for(int i=0; i<6; i++)
{

    glFramebufferTexture2D( GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT ,  GL_TEXTURE_CUBE_MAP_POSITIVE_X+i, fbo->GetTexture(), 0);
    
  


    ////////////////////////
    ////////////////////////
    ////////////////////////

    ///Draw Data



    matrix_math::Mat4X4<float> viewMatrix = cameraDirection;
    //---


/*
    glBindBuffer( GL_UNIFORM_BUFFER, UniformBufferTransPHandle );
        glBufferSubData( GL_UNIFORM_BUFFER, 0, sizeof(ModelViewMatrix), &ModelViewMatrix.matrixA[0]);
    glBindBuffer(GL_UNIFORM_BUFFER, 0);
*/
    depthShader->UseShader();

    world.identityClear();
    world = matrix_math::MatrixTranslation(0.0f, 0.0f, 0.0f);
    //projection
    glUniform3fv(glGetUniformLocation(depthShader->GetHandle(), "lightPosition"), 1, lightPosition.getXYZ());
    glUniformMatrix4fv(glGetUniformLocation(depthShader->GetHandle(), "projectionMatrix"), 1, GL_FALSE, &projection.matrixA[0]);
    glUniformMatrix4fv(glGetUniformLocation(depthShader->GetHandle(), "viewMatrix"), 1, GL_FALSE, &viewMatrix.matrixA[0]);
    glUniformMatrix4fv(glGetUniformLocation(depthShader->GetHandle(), "worldMatrix"), 1, GL_FALSE, &world.matrixA[0]);

        myCube2->Draw();
    depthShader->StopShader();

    glFinish();
    //---

    //matrix_math::Mat4X4<float> pMatrix = matrix_math::MatrixTranslation(0.0f, 0.0f, -1.0f) * matrix_math::MatrixScale(5.0f, 5.0f, 1.0f) * ModelViewMatrix;
    //ModelViewMatrix *= matrix_math::MatrixScale(5.0f, 5.0f, 1.0f);// * matrix_math::MatrixTranslation(0.0f, 0.0f, -2.0f);


/*
    glBindBuffer( GL_UNIFORM_BUFFER, UniformBufferTransPHandle );
        glBufferSubData( GL_UNIFORM_BUFFER, 0, sizeof(ModelViewMatrix), &pMatrix.matrixA[0]);
    glBindBuffer(GL_UNIFORM_BUFFER, 0);
*/

    depthShader->UseShader();

    world.identityClear();
    world =  matrix_math::MatrixScale(5.0f, 5.0f, 1.0f) * matrix_math::MatrixTranslation(0.0f, 0.0f, -1.0f);
    //projection


    glUniformMatrix4fv(glGetUniformLocation(depthShader->GetHandle(), "projectionMatrix"), 1, GL_FALSE, &projection.matrixA[0]);
    glUniformMatrix4fv(glGetUniformLocation(depthShader->GetHandle(), "viewMatrix"), 1, GL_FALSE, &viewMatrix.matrixA[0]);
    glUniformMatrix4fv(glGetUniformLocation(depthShader->GetHandle(), "worldMatrix"), 1, GL_FALSE, &world.matrixA[0]);

       myPlane2->Draw();
    depthShader->StopShader();

    glFinish();



    ////////////////////////
    ////////////////////////
    ////////////////////////
    ////////////////////////

}
}
////////////
////////////
/////////////
///////////////

void Render()
{
    fbo->UseBuffer();
        glCullFace( GL_FRONT );
          RenderFBO();
        glCullFace( GL_BACK );
    fbo->StopBuffer();

    glFlush();


    projection = matrix_math::PerspectiveMatrix<float>(45.0f, float(Width)/float(Height), 0.1f, 100.0f);
    static float dt = 0.0f;

    if( runTime )
        dt += 0.1f;

  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);		// Clear The Screen And The Depth Buffer
  glLoadIdentity();


    matrix_math::Mat4X4<float> lookAtCam = matrix_math::LookAtMatrix(movement[0], movement[1], movement[2], movement[4], 0.0f, 0.0f, 0.0f, 0.0f, 1.0f);

    matrix_math::Mat4X4<float> ModelViewMatrix;
    matrix_math::Mat4X4<float> viewMatrix;
    matrix_math::Mat4X4<float> worldMatrix;

    ModelViewMatrix = lookAtCam;

    ///Look into how to calculate the normal matrix
    matrix_math::Mat4X4<float> NormalMatrix;
    matrix_math::Mat4X4<float> NormalMatrixTmp;


    ////////////////////////
    ////////////////////////
    ////////////////////////


    ///Set Data

    //vector_math::Vec4<float> LightPosition = matrix_math::matrixVecMultiply<float>( ModelViewMatrix , vector_math::Vec4<float>(movementL[0], movementL[1], movementL[2], 1.0f) ); //Should have beenm fine but it's off
    //vector_math::Vec4<float> LightPosition = vector_math::Vec4<float>(movementL[0], movementL[1], movementL[2], 1.0f); //OKAY!!
    vector_math::Vec3<float> LightPosition = vector_math::Vec3<float>(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]); //OKAY!!
    vector_math::Vec3<float> eyePosition = vector_math::Vec3<float>(movement[0], movement[1], movement[2]); //OKAY!!



    ///PointLight Visual
    showLightPosition->UseShader();

        worldMatrix.identityClear();
        worldMatrix = matrix_math::MatrixTranslation(4.0f*cos(dt*0.5f), 4.0f*sin(dt*0.5f), movementL[2]);
        viewMatrix = lookAtCam;
        //projection

        glUniformMatrix4fv( glGetUniformLocation(showLightPosition->GetHandle(), "worldMatrix"), 1, GL_FALSE, &worldMatrix.matrixA[0]);
        glUniformMatrix4fv( glGetUniformLocation(showLightPosition->GetHandle(), "viewMatrix"), 1, GL_FALSE, &viewMatrix.matrixA[0]);
        glUniformMatrix4fv( glGetUniformLocation(showLightPosition->GetHandle(), "projectionMatrix"), 1, GL_FALSE, &projection.matrixA[0]);

        GLuint attribPos = glGetAttribLocation(showLightPosition->GetHandle(), "Vertex");

        glBindBuffer(GL_ARRAY_BUFFER, pointBuffer);
        glVertexAttribPointer(attribPos, 1, GL_FLOAT, GL_FALSE, sizeof(float)*4, 0);

        glEnableVertexAttribArray( attribPos );
        glDrawArrays(GL_POINTS, 0, 1);
        glBindBuffer(GL_ARRAY_BUFFER, 0);

    showLightPosition->StopShader();

glFinish();

    ///Set Data For Light Shader
    lightProp.color = vector_math::Vec4<float>(1.0f, 1.0f, 1.0f, 1.0f);
    lightProp.ambientColor = vector_math::Vec4<float>(0.0f, 0.0f, 0.0f, 1.0f);
    lightProp.specColor = vector_math::Vec4<float>(1.0f, 0.0f, 0.0f, 1.0f);
    lightProp.shine = 1.0f;

    glProgramUniform4fvEXT(pointlight_shader_15->GetHandle(), LColor, 1, lightProp.color.getXYZW());
    glProgramUniform4fvEXT(pointlight_shader_15->GetHandle(), LSpec , 1, lightProp.specColor.getXYZW());
    glProgramUniform4fvEXT(pointlight_shader_15->GetHandle(), LAmb  , 1, lightProp.ambientColor.getXYZW());
    glProgramUniform1fEXT (pointlight_shader_15->GetHandle(), LShine, lightProp.shine);

    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), uniformProjectionMatrix, 1, GL_FALSE, &projection.matrixA[0]);
    glProgramUniform3fvEXT(pointlight_shader_15->GetHandle(), uniformLP, 1, LightPosition.getXYZ());
    glProgramUniform3fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "eyePosition"), 1, eyePosition.getXYZ());


glFinish();

/*
    glBindBuffer( GL_UNIFORM_BUFFER, UniformBufferTransPHandle );
        glBufferSubData( GL_UNIFORM_BUFFER, 0, sizeof(ModelViewMatrix), &ModelViewMatrix.matrixA[0]);
    glBindBuffer(GL_UNIFORM_BUFFER, 0);
*/
    ///Draw Data

    worldMatrix.identityClear();
    worldMatrix = matrix_math::MatrixTranslation(0.0f, 0.0f, 0.0f);
    viewMatrix = lookAtCam;
    //projection

    NormalMatrix.identityClear();
    NormalMatrixTmp.identityClear();
    NormalMatrixTmp = matrix_math::MatrixInverse( worldMatrix );
    NormalMatrix = matrix_math::MatrixTranspose( NormalMatrixTmp );

    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "worldMatrix"), 1, GL_FALSE, &worldMatrix.matrixA[0]);
    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "viewMatrix"), 1, GL_FALSE, &viewMatrix.matrixA[0]);

    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "NormalMatrix"), 1, GL_FALSE, &NormalMatrix.matrixA[0]);

    pointlight_shader_15->UseShader();
        glUniform4f(glGetUniformLocation(pointlight_shader_15->GetHandle(), "matColor")  , 1.0f, 1.0f, 1.0f, 1.0f);
        glUniform1i(uniformSwitch, 0);
        myCube->Draw();
    pointlight_shader_15->StopShader();

glFinish();

    //matrix_math::Mat4X4<float> pMatrix = ModelViewMatrix * matrix_math::MatrixScale(5.0f, 5.0f, 1.0f) *  matrix_math::MatrixTranslation(0.0f, 0.0f, -1.0f);
    //ModelViewMatrix *= matrix_math::MatrixScale(5.0f, 5.0f, 1.0f);// * matrix_math::MatrixTranslation(0.0f, 0.0f, -2.0f);





/*
    glBindBuffer( GL_UNIFORM_BUFFER, UniformBufferTransPHandle );
        glBufferSubData( GL_UNIFORM_BUFFER, 0, sizeof(pMatrix), &pMatrix.matrixA[0]);
    glBindBuffer(GL_UNIFORM_BUFFER, 0);
*/
    //glPolygonMode( GL_FRONT_AND_BACK, GL_LINE );
    //glLineWidth(2.0);

    fbo->UseRenderTexture();



    pointlight_shader_15->UseShader();
        glUniform1f(glGetUniformLocation(pointlight_shader_15->GetHandle(), "time")  , dt);
        glUniform4f(glGetUniformLocation(pointlight_shader_15->GetHandle(), "matColor")  , 1.0f, 1.0f, 1.0f, 1.0f);
        glUniform1i(uniformSwitch, 2);

    worldMatrix.identityClear();
    worldMatrix = matrix_math::MatrixScale(5.0f, 5.0f, 1.0f) * matrix_math::MatrixTranslation(0.0f, 0.0f, -1.0f);
    viewMatrix = lookAtCam;
    //projection

    NormalMatrix.identityClear();
    NormalMatrixTmp.identityClear();
    NormalMatrixTmp = matrix_math::MatrixInverse( worldMatrix );
    NormalMatrix = matrix_math::MatrixTranspose( NormalMatrixTmp );

    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "worldMatrix"), 1, GL_FALSE, &worldMatrix.matrixA[0]);
    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "viewMatrix"), 1, GL_FALSE, &viewMatrix.matrixA[0]);

    glProgramUniformMatrix4fvEXT(pointlight_shader_15->GetHandle(), glGetUniformLocation(pointlight_shader_15->GetHandle(), "NormalMatrix"), 1, GL_FALSE, &NormalMatrix.matrixA[0]);

        myPlane->Draw();///

    pointlight_shader_15->StopShader();


    ////////////////////////
    ////////////////////////
    ////////////////////////
    ////////////////////////

    glFinish();

  // swap buffers to display, since we're double buffered.
  SDL_GL_SwapBuffers();
}
I say depthshader but I just render a reguler white shader since I was thinking the depth buffer would do it for me instead. int the frag shader i use samplerCubeShadow and feed in a normalized -lightvec.xyz and make q = 0.0. Tell me if i left out some info. I've trying to follow the directx cubmap shadow tutorial that can be found on gamedev and adapt it to opengl.
Advertisement
sorry if it seems a little weird I plan to clean up later since it's supposed to just get this working anyway.
Sorry but I really need help on this (I've been trying for some time).

Would it be better to just have a depth shader and calculate the depth from the shader rather than using the depth buffer?


If I use a depth buffer are the values from 0 to zfar value or 0 to 1 (assuming floating point)?

When I try to create the view from the point lights perspective am I supposed to feed this into gl_Position

gl_Position = Vertices * worldMatrix * viewMatrix * perspectiveMatrix;

Assuming that the objects position is at (0,0,0) and the viewMatrix is supposed to match the light's position(depending the on the cubemap ie +x, -x, etc)?

Finally, should I clear the depth buffer for ever part of the cubemap attached to the FBO or just once...

glClear(GL_DEPTH_BUFFER_BIT);
for(int i=0; i<6; i++)
{
glFrameBufferTexture(GL_CUBEMAP_POSITIVE_X + i)
RenderObjects();
}

or like this

for(int i=0; i<6; i++)
{
glClear(GL_DEPTH_BUFFER_BIT);
glFrameBufferTexture(GL_CUBEMAP_POSITIVE_X + i)
RenderObjects();
}

I've done shadows for spot lights but for some reason I can't wrap my mind around this(shadows using a cubemap for point lights) and am most likely missing some small detail that I;ve missed but I'm not sure what.

This topic is closed to new replies.

Advertisement

Popular Topics

aigan
The promise of freedom in story games Game Design and Theory
Nosey
Ideas for a new genre (anonimous) Game Design and Theory
KielanT
DirectX 12 Renderer Graphics and GPU Programming
MrK45
Inheriting from application registered class AngelCode
Advertisement

Recommended Tutorials

TheItalianJob71
A Resource Manager for Game Assets General and Gameplay Programming
GameDev.net
Huffman Compression General and Gameplay Programming
JoshuaWaring
Cache In A Multi-Core Environment General and Gameplay Programming
Alconost
When do videos need voiceovers? Music and Sound FX
Myopic Rhino
Dynamic 3D Scene Graphs Graphics and GPU Programming

Reticulating splines

About GameDev.net
Community Guidelines
Terms of Service
Privacy Policy
Contact Us
Copyright (c) 1999-2024 GameDev.net, LLC
Back to Top