MF_API void MFView_TransformPoint3DTo2D(const MFVector& point, MFVector *pResult)
{
MFMatrix proj, viewProj, view;
// get the perspective projection matrix
proj.SetPerspective(pCurrentView->fov, pCurrentView->nearPlane, pCurrentView->farPlane, pCurrentView->aspectRatio);
// in this special case, we'll make the projection matrix produce a 0-1 value in z across all platforms (some platforms project into different 'z' spaces)
float zn = pCurrentView->nearPlane;
float zf = pCurrentView->farPlane;
float zd = zf-zn;
float zs = zf/zd;
proj.m[10] = zs;
proj.m[14] = -zn*zs;
// get the view matrix (which we will need to calculate if we are in ortho mode)
if(!MFView_IsOrtho())
view = MFView_GetWorldToViewMatrix();
else
view.Inverse(MFView_GetCameraMatrix());
viewProj.Multiply4x4(view, proj);
// apply the projection and perform the perspective divide
MFVector transformed;
transformed = ApplyMatrix(point, viewProj);
transformed *= MFRcp(transformed.w);
// and shift the result into the ortho rect
transformed.x += 1.0f;
transformed.y = -transformed.y + 1.0f;
*pResult = transformed * MakeVector(pCurrentView->orthoRect.width*0.5f, pCurrentView->orthoRect.height*0.5f) + MakeVector(pCurrentView->orthoRect.x, pCurrentView->orthoRect.y);
}
MF_API const MFMatrix& MFView_GetWorldToScreenMatrix()
{
if(pCurrentView->viewProjDirty)
{
pCurrentView->viewProj.Multiply4x4(MFView_GetWorldToViewMatrix(), MFView_GetViewToScreenMatrix());
pCurrentView->viewProjDirty = false;
}
return pCurrentView->viewProj;
}
MF_API void MFView_TransformPoint2DTo3D(const MFVector& point, MFVector *pResult, MFVector *pResultRayDir)
{
MFMatrix proj, viewProj, view;
// get the perspective projection matrix
proj.SetPerspective(pCurrentView->fov, pCurrentView->nearPlane, pCurrentView->farPlane, pCurrentView->aspectRatio);
// in this special case, we'll make the projection matrix produce a 0-1 value in z across all platforms (some platforms project into different 'z' spaces)
float zn = pCurrentView->nearPlane;
float zf = pCurrentView->farPlane;
float zd = zf-zn;
float zs = zf/zd;
proj.m[10] = zs;
proj.m[14] = -zn*zs;
// get the view matrix (which we will need to calculate if we are in ortho mode)
if(!MFView_IsOrtho())
view = MFView_GetWorldToViewMatrix();
else
view.Inverse(MFView_GetCameraMatrix());
viewProj.Multiply4x4(view, proj);
// inverse projection
viewProj.Inverse();
// which the point from ortho space back into homogeneous space
*pResult = point;
*pResult -= MakeVector(pCurrentView->orthoRect.x, pCurrentView->orthoRect.y);
*pResult *= MakeVector(MFRcp(pCurrentView->orthoRect.width*0.5f), MFRcp(pCurrentView->orthoRect.height*0.5f));
pResult->x -= 1.0f;
pResult->y = -pResult->y + 1.0f;
// and un-project
// TODO: undo the perspective divide (f**k)
*pResult = ApplyMatrix(*pResult, viewProj);
if(pResultRayDir)
{
// calculate the pixels rays direction..
}
}
MF_API MFMatrix* MFView_GetLocalToView(const MFMatrix& localToWorld, MFMatrix *pOutput)
{
pOutput->Multiply4x4(localToWorld, MFView_GetWorldToViewMatrix());
return pOutput;
}
MF_API void MFParticleSystem_Draw(MFParticleSystem *pParticleSystem)
{
int numParticles = pParticleSystem->particles.GetLength();
if(numParticles == 0)
return;
// render particles
MFView_Push();
MFMatrix ltv = MFView_GetWorldToViewMatrix();
MFView_SetCameraMatrix(MFMatrix::identity);
// update and draw each particle
if(pParticleSystem->params.rotationRate != 0.0f)
{
MFParticleSystem_DrawRotating(pParticleSystem, ltv);
MFView_Pop();
return;
}
float fadeStart = pParticleSystem->params.life - pParticleSystem->params.fadeDelay;
MFMaterial_SetMaterial(pParticleSystem->pMaterial);
MFPrimitive(PT_QuadList, 0);
MFBegin(numParticles * 2);
MFParticle **ppI = pParticleSystem->particles.Begin();
while(*ppI)
{
MFParticle *pParticle = *ppI;
float dt = MFSystem_TimeDelta();
pParticle->size += pParticleSystem->params.scaleRate * dt;
pParticle->velocity += pParticleSystem->params.force * dt;
pParticle->pos += pParticle->velocity * dt;
float halfSize = pParticle->size * 0.5f;
float alpha = MFMin(pParticle->life / fadeStart, 1.0f);
MFVector pos = ApplyMatrixH(pParticle->pos, ltv);
MFSetColourV(MakeVector(pParticle->colour, pParticle->colour.w * alpha));
MFSetTexCoord1(0, 0);
MFSetPosition(pos.x - halfSize, pos.y + halfSize, pos.z);
MFSetTexCoord1(1, 1);
MFSetPosition(pos.x + halfSize, pos.y - halfSize, pos.z);
pParticle->life -= dt;
if(pParticle->life < 0.0f)
pParticleSystem->particles.Destroy(ppI);
ppI++;
}
MFEnd();
MFView_Pop();
}
