IsVisible Method

Summary

Tests whether the specified LeadPoint structure is contained within this RasterRegion.

Syntax

Objective-C

C++/CLI

Java

Python

public bool IsVisible( 
   LeadPoint point 
)

- (BOOL)isVisible:(LeadPoint)point

public boolean isVisible( 
   LeadPoint point 
);

public: 
bool IsVisible(  
   LeadPoint point 
)

def IsVisible(self,point):

Parameters

point
The LeadPoint structure to test.

Return Value

true when point is contained within this RasterRegion; false, otherwise.

Example

This example will create a small elliptical region in an image, gets the RasterRegion object before resetting the image region. It will then switch the red and blue component of every pixel inside the region data.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
 
 
public void RasterRegionIsVisibleExample() 
{ 
   string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"); 
   string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1_IsVisibleRegion.bmp"); 
 
   using (RasterCodecs codecs = new RasterCodecs()) 
   { 
      // Load the source image 
      using (RasterImage image = codecs.Load(srcFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)) 
      { 
         // Add a small elliptical region 
         image.AddEllipseToRegion(null, new LeadRect(image.ImageWidth / 3, image.ImageHeight / 3, image.ImageWidth / 3, image.ImageHeight / 3), RasterRegionCombineMode.Set); 
 
         // Get the region 
         using (RasterRegion region = image.GetRegion(null)) 
         { 
            // Remove the region from the image 
            image.MakeRegionEmpty(); 
 
            // Loop the image pixels, if it is inside the region, switch 
            // the red and blue component of the pixel color 
            for (int y = 0; y < image.Height; y++) 
            { 
               for (int x = 0; x < image.Width; x++) 
               { 
                  // Check if this pixel is inside the region 
                  if (region.IsVisible(new LeadPoint(x, y))) 
                  { 
                     // Yes, flip its R and B component 
                     RasterColor color = image.GetPixelColor(y, x); 
                     color = new RasterColor(color.B, color.G, color.R); 
                     image.SetPixelColor(y, x, color); 
                  } 
               } 
            } 
         } 
         codecs.Save(image, destFileName, RasterImageFormat.Bmp, 24); 
      } 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}

Requirements

Target Platforms

Reference

RasterRegion Class

RasterRegion Members

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Help Version 22.0.2023.5.16

Leadtools Assembly

Introduction

Getting Started

Namespaces

Leadtools Namespace

Leadtools.ImageProcessing Namespace

Assemblies