Helper function for videomodelist.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@1736 dfc29bdd-3216-0410-991c-e03cc46cb475

include/IVideoModeList.h

@@ -33,6 +33,13 @@ namespace video
 		\return Size of screen in pixels of the specified video mode. */
 		virtual core::dimension2d<s32> getVideoModeResolution(s32 modeNumber) const = 0;
 
+		//! Get a supported screen size with certain constraints.
+		/** \param minSize: Minimum dimensions required.
+		\param maxSize: Maximum dimensions allowed.
+		\return Size of screen in pixels which matches the requirements.
+		as good as possible. */
+		virtual core::dimension2d<s32> getVideoModeResolution(const core::dimension2d<s32>& minSize, const core::dimension2d<s32>& maxSize) const = 0;
+
 		//! Get the pixel depth of a video mode in bits.
 		/** \param modeNumber: zero based index of the video mode.
 		\return Size of each pixel of the specified video mode in bits. */

include/irrMath.h

@@ -8,6 +8,7 @@
 #include "IrrCompileConfig.h"
 #include "irrTypes.h"
 #include <math.h>
+#include <stdlib.h> // for abs() etc.
 
 #if defined(_IRR_SOLARIS_PLATFORM_) || defined(__BORLANDC__) || defined (__BCPLUSPLUS__) || defined (_WIN32_WCE)
 	#define sqrtf(X) (f32)sqrt((f64)(X))

source/Irrlicht/CVideoModeList.cpp

@@ -3,6 +3,7 @@
 // For conditions of distribution and use, see copyright notice in irrlicht.h
 
 #include "CVideoModeList.h"
+#include "irrMath.h"
 
 namespace irr
 {
@@ -45,6 +46,45 @@ core::dimension2d<s32> CVideoModeList::getVideoModeResolution(s32 modeNumber) co
 }
 
 
+core::dimension2d<s32> CVideoModeList::getVideoModeResolution(
+		const core::dimension2d<s32>& minSize,
+		const core::dimension2d<s32>& maxSize) const
+{
+	u32 best=VideoModes.size();
+	// if only one or no mode
+	if (best<2)
+		return getVideoModeResolution(0);
+
+	u32 i;
+	for (i=0; i<VideoModes.size(); ++i)
+	{
+		if (VideoModes[i].size.Width>=minSize.Width &&
+			VideoModes[i].size.Height>=minSize.Height &&
+			VideoModes[i].size.Width<=maxSize.Width &&
+			VideoModes[i].size.Height<=maxSize.Height)
+			best=i;
+	}
+	// we take the last one found, the largest one fitting
+	if (best<VideoModes.size())
+		return VideoModes[best].size;
+	const u32 minArea = minSize.getArea();
+	const u32 maxArea = maxSize.getArea();
+	u32 minDist = 0xffffffff;
+	best=0;
+	for (i=0; i<VideoModes.size(); ++i)
+	{
+		const u32 area = VideoModes[i].size.getArea();
+		const u32 dist = core::min_(abs(minArea-area), abs(maxArea-area));
+		if (dist<minDist)
+		{
+			minDist=dist;
+			best=i;
+		}
+	}
+	return VideoModes[best].size;
+}
+
+
 //! Returns the pixel depth of a video mode in bits.
 s32 CVideoModeList::getVideoModeDepth(s32 modeNumber) const
 {

source/Irrlicht/CVideoModeList.h

@@ -27,6 +27,9 @@ namespace video
 		//! Returns the screen size of a video mode in pixels.
 		virtual core::dimension2d<s32> getVideoModeResolution(s32 modeNumber) const;
 
+		//! Returns the screen size of an optimal video mode in pixels.
+		virtual core::dimension2d<s32> getVideoModeResolution(const core::dimension2d<s32>& minSize, const core::dimension2d<s32>& maxSize) const;
+
 		//! Returns the pixel depth of a video mode in bits.
 		virtual s32 getVideoModeDepth(s32 modeNumber) const;