graphicsdeviceinterface/screendriver/inc/CoordTransformation.inl
author Faisal Memon <faisal.memon@nokia.com>
Fri, 25 Jun 2010 17:49:58 +0100
branchEGL_MERGE
changeset 105 158b2308cc08
parent 0 5d03bc08d59c
permissions -rw-r--r--
Fix def files so that the implementation agnostic interface definition has no non-standards defined entry points, and change the eglrefimpl specific implementation to place its private entry points high up in the ordinal order space in the implementation region, not the standards based entrypoints region.

// Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// Converts logical coordinate value to physical coordinate value.
// Then adjusts the value, assuming that it must be within the drawing rectangle.
// The first, "<0" check is arguable - should it be there or not!?
// Because it HIDES negative values of "x" coordinate, so possible programmer's errors!
// But with used logical to physical transformation it is possible that some logical
// coordinate value might be transformed to negative physical coordinate value and 
// then it has to be checked and set to 0.
// 
//

inline TInt Log2Phys(TInt aCoordVal, TInt aScalingOrigin, TInt aScalingFactor, TInt aSize) 
	{
	aCoordVal = aScalingOrigin + aCoordVal * aScalingFactor;
	return aCoordVal < 0 ? 0 : aCoordVal >= aSize ? (aSize - 1) : aCoordVal;
	}

//Converts logical coordinate value to physical coordinate value.
//Then adjusts the value, assuming that it represents right-bottom coordinate of the logical 
//rectangle. The first, "<0" check is arguable - should it be there or not!?
//Because it HIDES negative values of "x" coordinate, so possible programmer's errors!
//But with used logical to physical transformation it is possible that some logical
//coordinate value is transformed to negative physical coordinate value and then it has to
//be checked and set to 0.
inline TInt RBtmLog2Phys(TInt aCoordVal, TInt aScalingOrigin, TInt aScalingFactor, TInt aSize) 
	{
	aCoordVal = aScalingOrigin + aCoordVal * aScalingFactor;
	return aCoordVal < 0 ? 0 : aCoordVal > aSize ? aSize : aCoordVal;
	}