1 files changed, 95 insertions, 0 deletions
diff --git a/engines/zvision/render_table.cpp b/engines/zvision/render_table.cpp
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+++ b/engines/zvision/render_table.cpp
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+/* ScummVM - Graphic Adventure Engine
+*
+* ScummVM is the legal property of its developers, whose names
+* are too numerous to list here. Please refer to the COPYRIGHT
+* file distributed with this source distribution.
+*
+* 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.
+
+* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*
+*/
+
+#include "common/scummsys.h"
+
+#include "zvision/render_table.h"
+
+
+namespace ZVision {
+
+RenderTable::RenderTable(uint32 numRows, uint32 numColumns)
+		: _numRows(numRows),
+		  _numColumns(numColumns) {
+	assert(numRows != 0 && numColumns != 0);
+
+	_internalBuffer = new Common::Point[numRows * numColumns];
+}
+
+RenderTable::~RenderTable() {
+	delete[] _internalBuffer;
+}
+
+void RenderTable::setRenderState(RenderState newState) {
+	_renderState = newState;
+
+	switch (newState) {
+	case PANORAMA:
+		_panoramaOptions.fieldOfView = 60;
+		_panoramaOptions.linearScale = 1;
+		generatePanoramaLookupTable();
+		break;
+	case TILT:
+		generateTiltLookupTable();
+		break;
+	case FLAT:
+		// Intentionally left empty
+		break;
+	}
+}
+
+void RenderTable::generatePanoramaLookupTable() {
+	float fieldOfView = _panoramaOptions.fieldOfView;
+	float scale = _panoramaOptions.linearScale;
+
+	memset(_internalBuffer, 0, _numRows * _numColumns * sizeof(uint16));
+
+	float halfWidth = (float)_numColumns / 2.0f;
+	float halfHeight = (float)_numRows / 2.0f;
+
+	float fovRadians = (fieldOfView * M_PI / 180.0f);
+	float halfHeightOverTan = halfHeight / tan(fovRadians);
+	float tanOverHalfHeight = tan(fovRadians) / halfHeight;
+
+	for (uint32 x = 0; x < _numRows; x++) {
+		// Add an offset of 0.01 to overcome zero tan/atan issue (vertical line on half of screen)
+		float xPos = (float)x - halfWidth + 0.01;
+		float tempX = atan(xPos*tanOverHalfHeight);
+
+		int32 newX = floor(scale * halfHeightOverTan * tempX);// + half_w);
+		float cosX = cos(tempX);
+
+		for (uint32 y = 0; y < _numColumns; y++) {
+			int32 newY = floor(halfHeight + (y - halfHeight) * cosX);
+
+			uint32 index = x * _numColumns + y;
+			_internalBuffer[index].x = newX; //pixel index
+			_internalBuffer[index].y = newY; //pixel index
+		}
+	}
+}
+
+void RenderTable::generateTiltLookupTable() {
+
+}
+
+} // End of namespace ZVision