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scale raster and position correctly

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git-svn-id: http://svn.osgeo.org/qgis/trunk@316 c8812cc2-4d05-0410-92ff-de0c093fc19c
This commit is contained in:
stevehalasz 2003-12-03 04:04:30 +00:00
parent b18f5e3b13
commit d3bd11082e
1 changed files with 56 additions and 14 deletions
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70
src/qgsrasterlayer.cpp
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@ -19,6 +19,7 @@
#include <qpainter.h>
#include <stdio.h>
#include "qgspoint.h"
#include "qgsrect.h"
#include "qgsrasterlayer.h"
#include "gdal_priv.h"
@ -33,6 +34,27 @@ QgsRasterLayer::QgsRasterLayer(QString path, QString baseName)
gdalDataset = (GDALDataset *) GDALOpen( path, GA_ReadOnly );
std::cout << "Raster Count: " << gdalDataset->GetRasterCount() << std::endl;
double adfGeoTransform[6];
if( gdalDataset->GetGeoTransform( adfGeoTransform ) == CE_None )
{
printf( "Origin = (%.6f,%.6f)\n",
adfGeoTransform[0], adfGeoTransform[3] );
printf( "Pixel Size = (%.6f,%.6f)\n",
adfGeoTransform[1], adfGeoTransform[5] );
}
const char *projRef = gdalDataset->GetProjectionRef();
double XMax = adfGeoTransform[0] + gdalDataset->GetRasterXSize() * adfGeoTransform[1] +
gdalDataset->GetRasterYSize() * adfGeoTransform[2];
double YMin = adfGeoTransform[3] + gdalDataset->GetRasterXSize() * adfGeoTransform[4] +
gdalDataset->GetRasterYSize() * adfGeoTransform[5];
layerExtent.setXmax(XMax);
layerExtent.setXmin(adfGeoTransform[0]);
layerExtent.setYmax(adfGeoTransform[3]);
layerExtent.setYmin(YMin);
}
QgsRasterLayer::~QgsRasterLayer()
@ -60,6 +82,22 @@ void QgsRasterLayer::draw(QPainter * p, QgsRect * viewExtent, QgsCoordinateTrans
std::cout << "QgsRasterLayer::draw()" << std::endl;
std::cout << "gdalDataset->GetRasterCount(): " << gdalDataset->GetRasterCount() << std::endl;
std::cout << "Layer extent: " << layerExtent.stringRep() << std::endl;
// get dimensions of raster image in map coordinate space
QgsPoint topLeft = cXf->transform(layerExtent.xMin(), layerExtent.yMax());
QgsPoint bottomRight = cXf->transform(layerExtent.xMax(), layerExtent.yMin());
//QPoint topLeft = cXf->transform(topLeft);
//QPoint bottomRight = layerExtent.bottomRight();
//bottomRight = cXf->transform(bottomRight);
int lXSize = bottomRight.xToInt() - topLeft.xToInt();
int lYSize = bottomRight.yToInt() - topLeft.yToInt();
std::cout << "xMin: " << layerExtent.xMin() <<std::endl;
std::cout << "yMax: " << layerExtent.yMax() <<std::endl;
std::cout << "xMax: " << layerExtent.xMax() <<std::endl;
std::cout << "yMin: " << layerExtent.yMin() <<std::endl;
std::cout << "lXSize: " << lXSize <<std::endl;
std::cout << "lYSize: " << lYSize <<std::endl;
// if there is more than one raster band they can be for red, green, blue, etc.
// so this loop doesn't make much sense right now
@ -69,27 +107,31 @@ void QgsRasterLayer::draw(QPainter * p, QgsRect * viewExtent, QgsCoordinateTrans
// http://cugir.mannlib.cornell.edu/browse_map/quad_map.html
for (int i = 1; i <= gdalDataset->GetRasterCount(); i++) {
GDALRasterBand *gdalBand = gdalDataset->GetRasterBand( i );
std::cout << "gdalBand->GetOverviewCount(): " << gdalBand->GetOverviewCount() <<std::endl;
int nXSize = gdalBand->GetXSize();
int nYSize = gdalBand->GetYSize();
// read raster 1 line at a time
// display image at 0,0
for (int nYOff = 0; nYOff < nYSize; nYOff++) {
uint *scanline = (uint*) CPLMalloc(sizeof(uint)*nXSize);
CPLErr result = gdalBand->RasterIO(
GF_Read, 0, nYOff, nXSize, 1, scanline, nXSize, 1, GDT_UInt32, 0, 0 );
// read entire raster
// treat scandata as a pseudo-multidimensional array
// RasterIO() takes care of scaling down image
// TODO: need to clip to map size or we run out of memory when zooming in
uint *scandata = (uint*) CPLMalloc(sizeof(uint)*lXSize * sizeof(uint)*lYSize);
CPLErr result = gdalBand->RasterIO(
GF_Read, 0, 0, nXSize, nYSize, scandata, lXSize, lYSize, GDT_UInt32, 0, 0 );
GDALColorTable *colorTable = gdalBand->GetColorTable();
GDALColorTable *colorTable = gdalBand->GetColorTable();
// print each point in scanline using color looked up in color table
for (int i = 0; i < nXSize; i++) {
const GDALColorEntry *colorEntry = GDALGetColorEntry (colorTable, scanline[i]);
// print each point in scandata using color looked up in color table
for (int i = 0; i < lXSize; i++) {
for (int j =0; j < lYSize; j++) {
const GDALColorEntry *colorEntry = GDALGetColorEntry(colorTable, scandata[i*lXSize + j]);
p->setPen(QColor(colorEntry->c1, colorEntry->c2, colorEntry->c3));
p->drawPoint(i, nYOff);
p->drawPoint(topLeft.xToInt() + j, topLeft.yToInt() + i);
}
CPLFree(scanline);
}
CPLFree(scandata);
}
}