Openlayers STContains, intersecting lines
I have an app running OpenLayers and have come across an interesting problem.
I create a polygon, called Project. Then I have sub-projects that are inside that polygon.
The first time you create a sub-project, I clip the sub-project so that it is inside the Project.
SpatialManager.ClipShape(subShape, projectShape);
When you go to edit a project, I want to make sure that you keep the sub-project inside the Project.
if(projectShape.STContains(subShape).isFalse)
The problem comes with the clipping/contains. When clipping, the project and sub-project share the same boundary lines.
STContains wont be true because they share lines.
Is there anyway to check if a polygon contains a percentage of another shape, or contains with sharing lines?
Thanks.
You are looking for STIntersects, which will return true if either polygon has any point in common with the other, including on an edge. You might also find STTouches useful, which will return true if two polygons touch, even at a single point, but do not have any interior points inside the other. STContains isn't working for you because the polygons share a common boundary, or to quote from the DE-9IM explained below:
Geometry b lies in the interior of a. Another definition: "a 'contains' b iff no points of b lie in the exterior of a, and at least one point of the interior of b lies in the interior of a
There is something with the slightly scary name of Dimensionally Extended nine-Intersection Model, which is abbreviated to DE-9IM for obvious reasons, which explains the underlying theory of spatial predicates.
- Is this declaration UB?
- Calling an external C function (in a shared lib) from Perl with Inline/C does not work
- Eclipse C/C++ how to find variable belongs to which struct quickly
- Is this truly best way to delete last element in C?
- Why do we need address virtualization in an operating system?
- Can a real floating-point type alias a complex floating-point type in C?
- Shadowing an iterator inside a for loop has undefined (?) behaviour in C
- Can a C program execute successfully if main() is defined as a macro?
- Ambiguity in scope of for loop declaration versus body
- Understanding the difference in timing of two functions that increment each element of an integer array
- Why MSVC generates warning C4127 when constant is used in "while" - C
- Executing a user-space function from the kernel space
- Why must the variable used to hold getchar's return value be declared as int?
- mpirun -np 4 ./a.out doesn't use all my cores (ubuntu 24.04LTS)
- Sleep for N seconds and wait for keypress
- Dereference twice in gdb
- Is it safe to cast a struct pointer to a different struct pointer having a prefix of elements?
- Can a C compiler legally reject a program if its call stack depth exceeds a fixed limit at compile time?
- return type defaults to 'int' [-Wimplicit-int]
- What is the scope of `fesetround()`?
- Which specific optimization flag causes libm functions to be treated as pure?
- How to render text in SDL2?
- Why would you use 'extern "C++"'?
- Strange Behavior Compiler Ignoring NULL Check Unless I Print Something in the if Statement
- Fast inverse square root using fixed point instead of floating point
- What is the const qualifier attached to in C: the memory area or the pointer?
- GCC options for strictest C code?
- How to do an explicit fall-through in C
- How do compilers treat CONST qualifier when the pointer points to a memory location obtained with malloc()?
- C: cmocka headers - how to unittest?