Initial revision

source/gameengine/Rasterizer/RAS_FramingManager.cpp

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+/**
+ * $Id$
+ * ***** BEGIN GPL/BL DUAL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version. The Blender
+ * Foundation also sells licenses for use in proprietary software under
+ * the Blender License.  See http://www.blender.org/BL/ for information
+ * about this.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL/BL DUAL LICENSE BLOCK *****
+ */
+
+#include "RAS_FramingManager.h"
+
+#include "RAS_Rect.h"
+
+	void
+RAS_FramingManager::
+ComputeDefaultFrustum(
+	const float camnear,
+	const float camfar,
+	const float lens,
+	const float design_aspect_ratio,
+	RAS_FrameFrustum & frustum
+){
+		
+	/*
+	 * Magic Blender calculation.
+	 * Blender does not give a Field of View as lens but a size
+	 * at 16 units away from the lens.
+	 */
+	float halfSize = 16.f * camnear / lens;
+	float sizeX;
+	float sizeY;
+
+	if (design_aspect_ratio > 1.f) {
+		// halfsize defines the width
+		sizeX = halfSize;
+		sizeY = halfSize/design_aspect_ratio;
+	} else {
+		// halfsize defines the height
+		sizeX = halfSize * design_aspect_ratio;
+		sizeY = halfSize;
+	}
+		
+	frustum.x2 = sizeX;
+	frustum.x1 = -frustum.x2;
+	frustum.y2 = sizeY;
+	frustum.y1 = -frustum.y2;
+	frustum.camnear = camnear;
+	frustum.camfar = camfar;
+}
+
+	void
+RAS_FramingManager::
+ComputeBestFitViewRect(
+	const RAS_Rect &availableViewport,
+	const float design_aspect_ratio,
+	RAS_Rect &viewport
+){
+	// try and honour the aspect ratio when setting the 
+	// drawable area. If we don't do this we are liable
+	// to get a lot of distortion in the rendered image.
+	
+	int width = availableViewport.GetWidth();
+	int height = availableViewport.GetHeight();
+	float window_aspect = float(width)/float(height);
+
+	if (window_aspect < design_aspect_ratio) {
+		int v_height = (int)(width / design_aspect_ratio); 
+		int left_over = (height - v_height) / 2; 
+			
+		viewport.SetLeft(availableViewport.GetLeft());
+		viewport.SetBottom(availableViewport.GetBottom() + left_over);
+		viewport.SetRight(availableViewport.GetLeft() + width);
+		viewport.SetTop(availableViewport.GetBottom() + left_over + v_height);
+
+	} else {
+		int v_width = (int)(height * design_aspect_ratio);
+		int left_over = (width - v_width) / 2; 
+
+		viewport.SetLeft(availableViewport.GetLeft() + left_over);
+		viewport.SetBottom(availableViewport.GetBottom());
+		viewport.SetRight(availableViewport.GetLeft() + v_width + left_over);
+		viewport.SetTop(availableViewport.GetBottom() + height);
+	}
+}
+
+	void
+RAS_FramingManager::
+ComputeViewport(
+	const RAS_FrameSettings &settings,
+	const RAS_Rect &availableViewport,
+	RAS_Rect &viewport
+){
+
+	RAS_FrameSettings::RAS_FrameType type = settings.FrameType();
+	const int winx = availableViewport.GetWidth();
+	const int winy = availableViewport.GetHeight();
+
+	const float design_width = float(settings.DesignAspectWidth());
+	const float design_height = float(settings.DesignAspectHeight());
+
+	float design_aspect_ratio = float(1);
+
+	if (design_height == float(0)) {
+		// well this is ill defined 
+		// lets just scale the thing
+
+		type = RAS_FrameSettings::e_frame_scale;
+	} else {
+		design_aspect_ratio = design_width/design_height;
+	}
+
+	switch (type) {
+
+		case RAS_FrameSettings::e_frame_scale :
+		case RAS_FrameSettings::e_frame_extend:
+		{
+			viewport.SetLeft(availableViewport.GetLeft());
+			viewport.SetBottom(availableViewport.GetBottom());
+			viewport.SetRight(availableViewport.GetLeft() + int(winx));
+			viewport.SetTop(availableViewport.GetBottom() + int(winy));
+
+			break;
+		}
+
+		case RAS_FrameSettings::e_frame_bars:
+		{
+			ComputeBestFitViewRect(
+				availableViewport,
+				design_aspect_ratio,	
+				viewport
+			);
+		
+			break;
+		}
+		default :
+			break;
+	}
+}
+
+	void
+RAS_FramingManager::
+ComputeFrustum(
+	const RAS_FrameSettings &settings,
+	const RAS_Rect &availableViewport,
+	const RAS_Rect &viewport,
+	const float lens,
+	const float camnear,
+	const float camfar,
+	RAS_FrameFrustum &frustum
+){
+
+	const int winx = availableViewport.GetWidth();
+	const int winy = availableViewport.GetHeight();
+
+	RAS_FrameSettings::RAS_FrameType type = settings.FrameType();
+
+	const float design_width = float(settings.DesignAspectWidth());
+	const float design_height = float(settings.DesignAspectHeight());
+
+	float design_aspect_ratio = float(1);
+
+	if (design_height == float(0)) {
+		// well this is ill defined 
+		// lets just scale the thing
+
+		type = RAS_FrameSettings::e_frame_scale;
+	} else {
+		design_aspect_ratio = design_width/design_height;
+	}
+	
+	ComputeDefaultFrustum(
+		camnear,
+		camfar,
+		lens,
+		design_aspect_ratio,
+		frustum
+	);
+
+	switch (type) {
+
+		case RAS_FrameSettings::e_frame_extend:
+		{
+			RAS_Rect vt;
+			ComputeBestFitViewRect(
+				availableViewport,
+				design_aspect_ratio,	
+				vt
+			);
+
+			// now scale the calculated frustum by the difference
+			// between vt and the viewport in each axis.
+			// These are always > 1
+
+			float x_scale = float(viewport.GetWidth())/float(vt.GetWidth());
+			float y_scale = float(viewport.GetHeight())/float(vt.GetHeight());
+
+			frustum.x1 *= x_scale;
+			frustum.x2 *= x_scale;
+			frustum.y1 *= y_scale;
+			frustum.y2 *= y_scale;
+	
+			break;
+		}	
+		case RAS_FrameSettings::e_frame_scale :
+		case RAS_FrameSettings::e_frame_bars:
+		default :
+			break;
+	}
+}	
+
+
+