Method UpdateConstants

GTE/Samples/Graphics/Lights/LightsWindow3.cpp:342–385

}

void LightsWindow3::UpdateConstants()
{
    // The pvw-matrices are updated automatically whenever the camera moves
    // or the trackball is rotated, which happens before this call.  Here we
    // need to update the camera model position, light model position, and
    // light model direction.

    // Compute the model-to-world transforms for the planes and spheres.
    Matrix4x4<float> wMatrix[GNUM][SNUM];
    Matrix4x4<float> rotate = mTrackBall.GetOrientation();
    wMatrix[GPLN][SVTX] = DoTransform(rotate, mPlane[SVTX]->worldTransform.GetHMatrix());
    wMatrix[GPLN][SPXL] = DoTransform(rotate, mPlane[SPXL]->worldTransform.GetHMatrix());
    wMatrix[GSPH][SVTX] = DoTransform(rotate, mSphere[SVTX]->worldTransform.GetHMatrix());
    wMatrix[GSPH][SPXL] = DoTransform(rotate, mSphere[SPXL]->worldTransform.GetHMatrix());

    // Compute the world-to-model transforms for the planes and spheres.
    Matrix4x4<float> invWMatrix[GNUM][SNUM];
    for (int32_t gt = 0; gt < GNUM; ++gt)
    {
        for (int32_t st = 0; st < SNUM; ++st)
        {
            invWMatrix[gt][st] = Inverse(wMatrix[gt][st]);
        }
    }

    Vector4<float> cameraWorldPosition = mCamera->GetPosition();
    for (int32_t lt = 0; lt < LNUM; ++lt)
    {
        for (int32_t gt = 0; gt < GNUM; ++gt)
        {
            for (int32_t st = 0; st < SNUM; ++st)
            {
                auto effect = mEffect[lt][gt][st];
                auto lighting = mEffect[lt][gt][st]->GetLighting();
                auto geometry = mEffect[lt][gt][st]->GetGeometry();
                auto const& invwmat = invWMatrix[gt][st];
                geometry->lightModelPosition = DoTransform(invwmat, mLightWorldPosition[st]);
                geometry->lightModelDirection = DoTransform(invwmat, mLightWorldDirection);
                geometry->cameraModelPosition = DoTransform(invwmat, cameraWorldPosition);
                effect->UpdateGeometryConstant();
            }
        }
    }
}