# Volume cannot display in in iOS

**URL:** https://discourse.vtk.org/t/volume-cannot-display-in-in-ios/2807
**Category:** Support
**Created:** [March 12, 2020, 4:04am UTC](https://discourse.vtk.org/t/volume-cannot-display-in-in-ios/2807 "2020-03-12T04:04:25Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![cocacc](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/c/77aa72/32.png) [@cocacc](https://discourse.vtk.org/u/cocacc)
#### Post date: [March 12, 2020, 4:04am UTC](https://discourse.vtk.org/t/volume-cannot-display-in-in-ios/2807/1 "2020-03-12T04:04:25Z")

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I want to display Volume in iPhone (iPhone xR os 13.4 Xcode 11.3.1 VTK 8.2.0）

I use Examples /VTK-8.2.0/Examples/iOS/VolumeRender

but I got the error message：  
**Generic Warning: In /VTK-8.2.0/Rendering/OpenGL2/vtkOpenGLState.cxx, line 617**

**Error glEnable/Disable1 OpenGL errors detected**

**0 : (1286) Unknown error**

**with stack trace of**

**WARNING: The stack could not be examined because backtrace is not supported.**

**Generic Warning: In /VTK/build/CMakeExternals/Build/vtk-ios-device-arm64/Rendering/OpenGL2/vtkOpenGLError.h, line 207**

**Failed to allocate 3D texture.1 OpenGL errors detected**

**0 : (1282) Invalid operation**

**ERROR: In /VTK-8.2.0/Rendering/VolumeOpenGL2/vtkVolumeTexture.cxx, line 762**

**vtkVolumeTexture (0x10460e340): Texture 3D allocation failed!**

**ERROR: In /VTK-8.2.0/Rendering/OpenGL2/vtkShaderProgram.cxx, line 461**

**vtkShaderProgram (0x2816b0870): 1: #version 300 es**

**ERROR: In /VTK-8.2.0/Rendering/OpenGL2/vtkShaderProgram.cxx, line 462**

**vtkShaderProgram (0x2816b0870): ERROR: 0:416: ‘/’ does not operate on ‘vec2’ and 'ivec2’**

**ERROR: 0:417: Use of undeclared identifier 'jitterValue’**

**ERROR: In /VTK-8.2.0/Rendering/VolumeOpenGL2/vtkOpenGLGPUVolumeRayCastMapper.cxx, line 3029**

**vtkOpenGLGPUVolumeRayCastMapper (0x107d07200): Shader failed to compile**

I don’t know how to solve it

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<div class="post-metadata">

### Author: ![wonki](https://discourse.vtk.org/user_avatar/discourse.vtk.org/wonki/32/2345_2.png) [@wonki](https://discourse.vtk.org/u/wonki)
#### Post date: [September 18, 2020, 2:44am UTC](https://discourse.vtk.org/t/volume-cannot-display-in-in-ios/2807/2 "2020-09-18T02:44:31Z")

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I have same issue too… Did you resolve this???