MapWinGIS ActiveX Control

MapWinGIS is distributed as an ActiveX Control DLL. The project structure is organized into core DLL management files and the specific Map control implementation.

Core DLL Files

• MapWinGIS.h: The primary include file for the ActiveX Control DLL.
• MapWinGIS.cpp: Handles DLL initialization, termination, and bookkeeping.
• MapWinGIS.def: Contains essential information required by Microsoft Windows to run the DLL.
• MapWinGIS.odl: Contains the Object Description Language source code for the control's type library.
• MapWinGIS.rc: Manages Windows resources used by the project.

Map Control Implementation

• Map.h / Map.cpp: Declares and implements the CMapView C++ class, which is the core map control.
• MapPpg.h / MapPpg.cpp: Declares and implements the CMapViewPropPage C++ class, used for property pages.
• Map.bmp: The bitmap used to represent the CMapView control on tool palettes.

Searching the ShapeLib quadtree is a multi-stage process designed to balance speed and accuracy. Developers implementing spatial queries should follow this pattern:

1. Phase 1: Quadtree Traversal: Use SHPTreeFindLikelyShapes() to traverse the quadtree. This collects the shapeids of all shapes contained in quadtree nodes whose bounding rectangles overlap the search rectangle. This phase may return "false positives" because a shape's bounding box is often significantly smaller than its containing tree node.
2. Phase 2: Shape Verification: Fetch the actual shapes associated with the collected shapeids and verify if their specific bounding boxes fall within the area of interest.
3. Phase 3: Geometry Verification (Optional): For high precision, verify if the actual line segments or geometry of the shape cross the area of interest. This is more complex and often handled by the drawing engine's clipping logic rather than the search index.

You can build ShapeLib on Unix, MinGW, MSYS, or Windows using the provided CMake build system. This system replaces the traditional Makefile and makefile.vc with a more flexible approach that supports full testing.

Prerequisites

1. Download eg_data (Optional): Download the example data tree (e.g., via wget http://dl.maptools.org/dl/shapelib/shape_eg_data.zip) to enable 'stream1' tests.
2. Download ShapeLib Source: Obtain shapelib-1.3.0.tar.gz from OSGeo and unpack it.
3. Prepare Source Tree:
   • Copy the CMakeLists.txt file from this repository into the top-level of the unpacked ShapeLib source tree.
   • Apply the shapelib.patch to the source tree using patch -p1 < path/to/shapelib.patch. This patch optionally quiets error messages when ShapeLib cannot open shapefiles.

Build Steps

Create a separate build directory to perform an out-of-source build.

1. Configure

Run cmake with your preferred compiler and options.

• Use -G "Unix Makefiles" for Linux/Unix.
• Use -G "MSYS Makefiles" for MinGW/MSYS.
• Use -DEG_DATA:PATH=<path> to specify the location of the eg_data directory. If this is not provided, 'stream1' tests will be skipped.

2. Build and Install

Use make to compile and install the library.

3. Test

Run ctest to execute the test suite.

# 1. Setup source (example assumes source is in ../shapelib-1.3.0)
mkdir build_dir
cd build_dir

# 2. Configure
# Note: -DEG_DATA:PATH is required for 'stream1' tests
env CC=gcc CFLAGS="-O3 -Wuninitialized" \
cmake \
-G "Unix Makefiles" \
-DCMAKE_INSTALL_PREFIX=/home/software/shapelib/install \
-DEG_DATA:PATH=/home/software/shapefile/eg_data/ \
../shapelib-1.3.0 >& cmake.out

# 3. Build and install
make VERBOSE=1 -j4 install >& install.out

# 4. Test
ctest

The Index class uses a Tools::PropertySet to configure the behavior and storage of the spatial index. When initializing or modifying an index, you can set several key properties via the m_properties object.

Supported Properties