/** Handles populating PVRShaman-specific content and delegates remainder to the standard population mechanisms. */
bool CC3PVRShamanShaderSemantics::populateUniform( CC3GLSLUniform* uniform, CC3NodeDrawingVisitor* visitor )
{
//LogTrace(@"%@ retrieving semantic value for %@", self, uniform.fullDescription);
GLenum semantic = uniform->getSemantic();
GLuint semanticIndex = uniform->getSemanticIndex();
GLint uniformSize = uniform->getSize();
CC3Viewport vp;
if ( super::populateUniform( uniform, visitor ) )
return true;
switch (semantic)
{
// Sets a vec2, specific to PVRShaman, that combines the falloff angle (in degrees) and exponent
case kCC3PVRShamanSemanticLightSpotFalloff:
for (GLint i = 0; i < uniformSize; i++)
{
CC3Light* light = visitor->getLightAt( semanticIndex + i );
uniform->setPoint( ccp(light->getSpotCutoffAngle(), light->getSpotExponent()), i );
}
return true;
case kCC3PVRShamanSemanticElapsedTimeLastFrame:
// Time of last frame. Just subtract frame time from current time
uniform->setFloat( visitor->getScene()->getElapsedTimeSinceOpened() - visitor->getDeltaTime() );
return true;
case kCC3PVRShamanSemanticViewportSize:
vp = visitor->getRenderSurface()->getViewport();
uniform->setPoint( ccp(vp.w, vp.h) );
return true;
case kCC3PVRShamanSemanticViewportClipping:
{
// Applies the field of view angle to the narrower aspect.
vp = visitor->getRenderSurface()->getViewport();
GLfloat aspect = (GLfloat) vp.w / (GLfloat) vp.h;
CC3Camera* cam = visitor->getCamera();
GLfloat fovWidth, fovHeight;
if (aspect >= 1.0f) { // Landscape
fovHeight = CC3DegToRad(cam->getEffectiveFieldOfView());
fovWidth = fovHeight * aspect;
} else { // Portrait
fovWidth = CC3DegToRad(cam->getEffectiveFieldOfView());
fovHeight = fovWidth / aspect;
}
uniform->setVector4( CC3Vector4(cam->getNearClippingDistance(), cam->getFarClippingDistance(), fovWidth, fovHeight) );
return true;
}
default:
return false;
}
}
void CC3Frustum::populateFrom( GLfloat fieldOfView, GLfloat aspect, GLfloat nearClip, GLfloat farClip )
{
GLfloat rightClip, topClip;
GLfloat halfFOV = fieldOfView / 2.0f;
// Apply the field of view angle to the narrower aspect.
if ( aspect >= 1.0f )
{ // Landscape
topClip = nearClip * tanf(CC3DegToRad(halfFOV));
rightClip = topClip * aspect;
}
else
{ // Portrait
rightClip = nearClip * tanf(CC3DegToRad(halfFOV));
topClip = rightClip / aspect;
}
populateRight( rightClip, topClip, nearClip, farClip );
}
/**
* Returns a point representing the top-right corner of the near clipping plane,
* expressed as a proportional multiple of the nearClippingDistance.
*
* The returned point will have the same aspect ratio as the viewport. The component
* values of the point are calculated taking into consideration the effectiveFieldOfView,
* fieldOfViewOrientation, and fieldOfViewAspectOrientation properties.
*/
CCPoint CC3Camera::getOrientedFieldOfViewAspect()
{
GLfloat halfFOV = getEffectiveFieldOfView() / 2.0f;
GLfloat aspect = ((GLfloat) _viewport.w / (GLfloat) _viewport.h);
GLfloat right, top, diag, orientationCorrection;
switch (_fieldOfViewOrientation)
{
case CC3FieldOfViewOrientationVertical:
top = tanf(CC3DegToRad(halfFOV));
right = top * aspect;
orientationCorrection = 1.0f / aspect;
break;
case CC3FieldOfViewOrientationDiagonal:
diag = tanf(CC3DegToRad(halfFOV));
top = diag / sqrtf((aspect * aspect) + 1.0f);
right = top * aspect;
orientationCorrection = 1.0f;
break;
case CC3FieldOfViewOrientationHorizontal:
default:
right = tanf(CC3DegToRad(halfFOV));
top = right / aspect;
orientationCorrection = aspect;
break;
}
// If the aspect doesn't match the intended orientation,
// bring them in alignment by scaling by the orientation correction.
if ((isDeviceOrientationLandscape(_fieldOfViewAspectOrientation) && (aspect < 1.0f)) ||
(isDeviceOrientationPortrait(_fieldOfViewAspectOrientation ) && (aspect > 1.0f)))
{
right *= orientationCorrection;
top *= orientationCorrection;
}
return ccp(right, top);
}
