diff --git a/util/test/demos/d3d11/d3d11_shader_editing.cpp b/util/test/demos/d3d11/d3d11_shader_editing.cpp
new file mode 100644
index 000000000..cecbb66ed
--- /dev/null
+++ b/util/test/demos/d3d11/d3d11_shader_editing.cpp
@@ -0,0 +1,111 @@
+/******************************************************************************
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019-2020 Baldur Karlsson
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ ******************************************************************************/
+
+#include "d3d11_test.h"
+
+RD_TEST(D3D11_Shader_Editing, D3D11GraphicsTest)
+{
+  static constexpr const char *Description =
+      "Ensures that shader editing works with different combinations of shader re-use.";
+
+  std::string vertex = R"EOSHADER(
+
+float4 main(float3 INpos : POSITION) : SV_Position
+{
+	float4 ret = float4(0,0,0,1);
+  ret.xyz += INpos.xyz;
+  return ret;
+}
+
+)EOSHADER";
+
+  std::string pixel = R"EOSHADER(
+
+float4 main() : SV_Target0
+{
+#if 1
+	return float4(0.0, 1.0, 0.0, 1.0);
+#else
+	return float4(0.0, 1.0, 1.0, 1.0);
+#endif
+}
+
+)EOSHADER";
+
+  int main()
+  {
+    // initialise, create window, create device, etc
+    if(!Init())
+      return 3;
+
+    ID3DBlobPtr vsblob = Compile(vertex, "main", "vs_4_0");
+    ID3DBlobPtr psblob = Compile(pixel, "main", "ps_4_0");
+
+    CreateDefaultInputLayout(vsblob);
+
+    ID3D11VertexShaderPtr vs = CreateVS(vsblob);
+    ID3D11PixelShaderPtr ps = CreatePS(psblob);
+
+    // compile again so that we can edit this one distinctly
+    ID3D11PixelShaderPtr ps2 = CreatePS(psblob);
+
+    ID3D11BufferPtr vb = MakeBuffer().Vertex().Data(DefaultTri);
+
+    ID3D11Texture2DPtr fltTex =
+        MakeTexture(DXGI_FORMAT_R32G32B32A32_FLOAT, screenWidth, screenHeight).RTV();
+    ID3D11RenderTargetViewPtr fltRT = MakeRTV(fltTex);
+
+    while(Running())
+    {
+      ClearRenderTargetView(bbRTV, {0.4f, 0.5f, 0.6f, 1.0f});
+      ClearRenderTargetView(fltRT, {0.4f, 0.5f, 0.6f, 1.0f});
+
+      IASetVertexBuffer(vb, sizeof(DefaultA2V), 0);
+      ctx->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+      ctx->IASetInputLayout(defaultLayout);
+
+      ctx->VSSetShader(vs, NULL, 0);
+      ctx->PSSetShader(ps, NULL, 0);
+
+      ctx->OMSetRenderTargets(1, &fltRT.GetInterfacePtr(), NULL);
+
+      RSSetViewport({0.0f, 0.0f, (float)screenWidth / 2.0f, (float)screenHeight, 0.0f, 1.0f});
+      setMarker("Draw 1");
+      ctx->Draw(3, 0);
+
+      ctx->PSSetShader(ps2, NULL, 0);
+
+      RSSetViewport({(float)screenWidth / 2.0f, 0.0f, (float)screenWidth / 2.0f,
+                     (float)screenHeight, 0.0f, 1.0f});
+      setMarker("Draw 2");
+      ctx->Draw(3, 0);
+
+      Present();
+    }
+
+    return 0;
+  }
+};
+
+REGISTER_TEST();
diff --git a/util/test/demos/d3d12/d3d12_shader_editing.cpp b/util/test/demos/d3d12/d3d12_shader_editing.cpp
new file mode 100644
index 000000000..dceaab696
--- /dev/null
+++ b/util/test/demos/d3d12/d3d12_shader_editing.cpp
@@ -0,0 +1,132 @@
+/******************************************************************************
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019-2020 Baldur Karlsson
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ ******************************************************************************/
+
+#include "d3d12_test.h"
+
+RD_TEST(D3D12_Shader_Editing, D3D12GraphicsTest)
+{
+  static constexpr const char *Description =
+      "Ensures that shader editing works with different combinations of shader re-use.";
+
+  std::string vertex = R"EOSHADER(
+
+float4 main(float3 INpos : POSITION) : SV_Position
+{
+	float4 ret = float4(0,0,0,1);
+  ret.xyz += INpos.xyz;
+  return ret;
+}
+
+)EOSHADER";
+
+  std::string pixel = R"EOSHADER(
+
+float4 main() : SV_Target0
+{
+#if 1
+	return float4(0.0, 1.0, 0.0, 1.0);
+#else
+	return float4(0.0, 1.0, 1.0, 1.0);
+#endif
+}
+
+)EOSHADER";
+
+  int main()
+  {
+    // initialise, create window, create device, etc
+    if(!Init())
+      return 3;
+
+    ID3DBlobPtr vsblob = Compile(vertex, "main", "vs_4_0");
+    ID3DBlobPtr psblob = Compile(pixel, "main", "ps_4_0");
+
+    // since we assign shader IDs based on blob hash, we need to make this blob slightly different
+    ID3DBlobPtr psblob2 = Compile(pixel + " ", "main", "ps_4_0");
+
+    ID3D12ResourcePtr vb = MakeBuffer().Data(DefaultTri);
+
+    ID3D12RootSignaturePtr sig = MakeSig({});
+
+    ID3D12PipelineStatePtr pso = MakePSO().RootSig(sig).InputLayout().VS(vsblob).PS(psblob).RTVs(
+        {DXGI_FORMAT_R32G32B32A32_FLOAT});
+    ID3D12PipelineStatePtr pso2 = MakePSO().RootSig(sig).InputLayout().VS(vsblob).PS(psblob2).RTVs(
+        {DXGI_FORMAT_R32G32B32A32_FLOAT});
+
+    ResourceBarrier(vb, D3D12_RESOURCE_STATE_COMMON, D3D12_RESOURCE_STATE_VERTEX_AND_CONSTANT_BUFFER);
+
+    ID3D12ResourcePtr rtvtex = MakeTexture(DXGI_FORMAT_R32G32B32A32_FLOAT, screenWidth, screenHeight)
+                                   .RTV()
+                                   .InitialState(D3D12_RESOURCE_STATE_RENDER_TARGET);
+
+    while(Running())
+    {
+      ID3D12GraphicsCommandListPtr cmd = GetCommandBuffer();
+
+      Reset(cmd);
+
+      ID3D12ResourcePtr bb = StartUsingBackbuffer(cmd, D3D12_RESOURCE_STATE_RENDER_TARGET);
+
+      D3D12_CPU_DESCRIPTOR_HANDLE bbrtv =
+          MakeRTV(bb).Format(DXGI_FORMAT_R8G8B8A8_UNORM_SRGB).CreateCPU(0);
+
+      D3D12_CPU_DESCRIPTOR_HANDLE offrtv = MakeRTV(rtvtex).CreateCPU(0);
+
+      ClearRenderTargetView(cmd, offrtv, {0.4f, 0.5f, 0.6f, 1.0f});
+      ClearRenderTargetView(cmd, bbrtv, {0.4f, 0.5f, 0.6f, 1.0f});
+
+      cmd->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+
+      IASetVertexBuffer(cmd, vb, sizeof(DefaultA2V), 0);
+      cmd->SetGraphicsRootSignature(sig);
+
+      RSSetScissorRect(cmd, {0, 0, screenWidth, screenHeight});
+
+      OMSetRenderTargets(cmd, {offrtv}, {});
+
+      RSSetViewport(cmd, {0.0f, 0.0f, (float)screenWidth / 2.0f, (float)screenHeight, 0.0f, 1.0f});
+      cmd->SetPipelineState(pso);
+      setMarker(cmd, "Draw 1");
+      cmd->DrawInstanced(3, 1, 0, 0);
+
+      RSSetViewport(cmd, {(float)screenWidth / 2.0f, 0.0f, (float)screenWidth / 2.0f,
+                          (float)screenHeight, 0.0f, 1.0f});
+      cmd->SetPipelineState(pso2);
+      setMarker(cmd, "Draw 2");
+      cmd->DrawInstanced(3, 1, 0, 0);
+
+      FinishUsingBackbuffer(cmd, D3D12_RESOURCE_STATE_RENDER_TARGET);
+
+      cmd->Close();
+
+      Submit({cmd});
+
+      Present();
+    }
+
+    return 0;
+  }
+};
+
+REGISTER_TEST();
diff --git a/util/test/demos/demos.vcxproj b/util/test/demos/demos.vcxproj
index efcc1a757..5dca80021 100644
--- a/util/test/demos/demos.vcxproj
+++ b/util/test/demos/demos.vcxproj
@@ -143,6 +143,7 @@
     <ClCompile Include="d3d11\d3d11_refcount_check.cpp" />
     <ClCompile Include="d3d11\d3d11_resource_lifetimes.cpp" />
     <ClCompile Include="d3d11\d3d11_saturate.cpp" />
+    <ClCompile Include="d3d11\d3d11_shader_editing.cpp" />
     <ClCompile Include="d3d11\d3d11_simple_dispatch.cpp" />
     <ClCompile Include="d3d11\d3d11_simple_triangle.cpp" />
     <ClCompile Include="d3d11\d3d11_stream_out.cpp" />
@@ -160,6 +161,7 @@
     <ClCompile Include="d3d12\d3d12_helpers.cpp" />
     <ClCompile Include="d3d12\d3d12_overlay_test.cpp" />
     <ClCompile Include="d3d12\d3d12_resource_lifetimes.cpp" />
+    <ClCompile Include="d3d12\d3d12_shader_editing.cpp" />
     <ClCompile Include="d3d12\d3d12_simple_triangle.cpp" />
     <ClCompile Include="d3d12\d3d12_test.cpp" />
     <ClCompile Include="d3d12\d3d12_texture_zoo.cpp" />
diff --git a/util/test/demos/demos.vcxproj.filters b/util/test/demos/demos.vcxproj.filters
index b78a923f0..835311d4b 100644
--- a/util/test/demos/demos.vcxproj.filters
+++ b/util/test/demos/demos.vcxproj.filters
@@ -367,6 +367,12 @@
     <ClCompile Include="vk\vk_separate_depth_stencil_layouts.cpp">
       <Filter>Vulkan\demos</Filter>
     </ClCompile>
+    <ClCompile Include="d3d11\d3d11_shader_editing.cpp">
+      <Filter>D3D11\demos</Filter>
+    </ClCompile>
+    <ClCompile Include="d3d12\d3d12_shader_editing.cpp">
+      <Filter>D3D12\demos</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <Filter Include="D3D11">
diff --git a/util/test/tests/D3D11/D3D11_Shader_Editing.py b/util/test/tests/D3D11/D3D11_Shader_Editing.py
new file mode 100644
index 000000000..156872cd5
--- /dev/null
+++ b/util/test/tests/D3D11/D3D11_Shader_Editing.py
@@ -0,0 +1,159 @@
+import copy
+import rdtest
+import renderdoc as rd
+from typing import Tuple
+
+
+class D3D11_Shader_Editing(rdtest.TestCase):
+    demos_test_name = 'D3D11_Shader_Editing'
+
+    def check_capture(self):
+        eid = self.find_draw("Draw 1").next.eventId
+        self.controller.SetFrameEvent(eid, False)
+
+        pipe: rd.PipeState = self.controller.GetPipelineState()
+
+        psrefl1: rd.ShaderReflection = pipe.GetShaderReflection(rd.ShaderStage.Pixel)
+
+        eid = self.find_draw("Draw 2").next.eventId
+        self.controller.SetFrameEvent(eid, False)
+
+        pipe: rd.PipeState = self.controller.GetPipelineState()
+
+        psrefl2: rd.ShaderReflection = pipe.GetShaderReflection(rd.ShaderStage.Pixel)
+        vsrefl: rd.ShaderReflection = pipe.GetShaderReflection(rd.ShaderStage.Vertex)
+
+        tex: rd.ResourceId = pipe.GetOutputTargets()[0].resourceId
+
+        # Both triangles should be green
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 0.0, 1.0])
+
+        rdtest.log.success("Values are as expected initially")
+
+        source: str = psrefl1.debugInfo.files[0].contents.replace('#if 1', '#if 0')
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(psrefl1.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Pixel)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        ps1 = newShader[0]
+
+        source: str = psrefl2.debugInfo.files[0].contents.replace('#if 1', '#if 0')
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(psrefl2.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Pixel)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        ps2 = newShader[0]
+
+        source: str = vsrefl.debugInfo.files[0].contents.replace('INpos.xyz', 'INpos.xyz+float3(1,1,1)')
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(vsrefl.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Vertex)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        offsetVS = newShader[0]
+
+        source: bytes = vsrefl.rawBytes
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(vsrefl.entryPoint,
+                                                                                 vsrefl.encoding, source,
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Vertex)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        nochangeVS = newShader[0]
+
+        # Edit both Pixel shaders
+        self.controller.ReplaceResource(psrefl1.resourceId, ps1)
+        self.controller.ReplaceResource(psrefl2.resourceId, ps2)
+
+        # Refresh the replay if it didn't happen already
+        self.controller.SetFrameEvent(eid, True)
+
+        # Triangles have green and blue channel
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 1.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after Pixel editing")
+
+        # Now "edit" the VS but don't change it. We should still get the same values
+        self.controller.ReplaceResource(vsrefl.resourceId, nochangeVS)
+        self.controller.SetFrameEvent(eid, True)
+
+        # Triangles have green and blue channel
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 1.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after no-op vertex editing")
+
+        # Change the VS to one that has ofpset the triangles off-centre
+        self.controller.ReplaceResource(vsrefl.resourceId, offsetVS)
+        self.controller.SetFrameEvent(eid, True)
+
+        # Original sample positions are now the clear color
+        self.check_pixel_value(tex, 0.25, 0.5, [0.4, 0.5, 0.6, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.4, 0.5, 0.6, 1.0])
+
+        # Triangles have green and blue channel
+        self.check_pixel_value(tex, 0.45, 0.05, [0.0, 1.0, 1.0, 1.0])
+        self.check_pixel_value(tex, 0.95, 0.05, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after ofpset vertex editing")
+
+        # Now undo the first ps edit
+        self.controller.RemoveReplacement(psrefl1.resourceId)
+        self.controller.SetFrameEvent(eid, True)
+
+        # Original sample positions are still the clear color
+        self.check_pixel_value(tex, 0.25, 0.5, [0.4, 0.5, 0.6, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.4, 0.5, 0.6, 1.0])
+
+        # The right triangle is the edited colour, the other two have reverted to green channel only
+        self.check_pixel_value(tex, 0.45, 0.05, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.95, 0.05, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after removing first Pixel edit")
+
+        # Now undo the first VS edit
+        self.controller.RemoveReplacement(vsrefl.resourceId)
+        self.controller.SetFrameEvent(eid, True)
+
+        # The right triangle is the edited colour, but they are back in the original positions
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after removing vertex edit")
+
+        # finally undo the second ps edit
+        self.controller.RemoveReplacement(psrefl2.resourceId)
+        self.controller.SetFrameEvent(eid, True)
+
+        # We should be back to where we started
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 0.0, 1.0])
+
+        rdtest.log.success("Values are as expected after removing all edits")
+
+        self.controller.FreeTargetResource(nochangeVS)
+        self.controller.FreeTargetResource(offsetVS)
+        self.controller.FreeTargetResource(ps1)
+        self.controller.FreeTargetResource(ps2)
diff --git a/util/test/tests/D3D12/D3D12_Shader_Editing.py b/util/test/tests/D3D12/D3D12_Shader_Editing.py
new file mode 100644
index 000000000..1c20acf5d
--- /dev/null
+++ b/util/test/tests/D3D12/D3D12_Shader_Editing.py
@@ -0,0 +1,161 @@
+import copy
+import rdtest
+import renderdoc as rd
+from typing import Tuple
+
+
+class D3D12_Shader_Editing(rdtest.TestCase):
+    demos_test_name = 'D3D12_Shader_Editing'
+
+    def check_capture(self):
+        eid = self.find_draw("Draw 1").next.eventId
+        self.controller.SetFrameEvent(eid, False)
+
+        pipe: rd.PipeState = self.controller.GetPipelineState()
+
+        psrefl1: rd.ShaderReflection = pipe.GetShaderReflection(rd.ShaderStage.Pixel)
+
+        eid = self.find_draw("Draw 2").next.eventId
+        self.controller.SetFrameEvent(eid, False)
+
+        pipe: rd.PipeState = self.controller.GetPipelineState()
+
+        psrefl2: rd.ShaderReflection = pipe.GetShaderReflection(rd.ShaderStage.Pixel)
+        vsrefl: rd.ShaderReflection = pipe.GetShaderReflection(rd.ShaderStage.Vertex)
+
+        tex: rd.ResourceId = pipe.GetOutputTargets()[0].resourceId
+
+        # Both triangles should be green
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 0.0, 1.0])
+
+        rdtest.log.success("Values are as expected initially")
+
+        source: str = psrefl1.debugInfo.files[0].contents.replace('#if 1', '#if 0')
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(psrefl1.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Pixel)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        ps1 = newShader[0]
+
+        source: str = psrefl2.debugInfo.files[0].contents.replace('#if 1', '#if 0')
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(psrefl2.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Pixel)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        ps2 = newShader[0]
+
+        source: str = vsrefl.debugInfo.files[0].contents.replace('INpos.xyz', 'INpos.xyz+float3(1,1,1)')
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(vsrefl.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Vertex)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        offsetVS = newShader[0]
+
+        # for D3D12 to ensure we get an actual different shader, we need to make a no-op source change
+        source: str = vsrefl.debugInfo.files[0].contents + ' '
+
+        newShader: Tuple[rd.ResourceId, str] = self.controller.BuildTargetShader(vsrefl.entryPoint,
+                                                                                 rd.ShaderEncoding.HLSL,
+                                                                                 bytes(source, 'UTF-8'),
+                                                                                 rd.ShaderCompileFlags(),
+                                                                                 rd.ShaderStage.Vertex)
+
+        if len(newShader[1]) != 0:
+            raise rdtest.TestFailureException("Failed to compile edited shader: {}".format(newShader[1]))
+
+        nochangeVS = newShader[0]
+
+        # Edit both Pixel shaders
+        self.controller.ReplaceResource(psrefl1.resourceId, ps1)
+        self.controller.ReplaceResource(psrefl2.resourceId, ps2)
+
+        # Refresh the replay if it didn't happen already
+        self.controller.SetFrameEvent(eid, True)
+
+        # Triangles have green and blue channel
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 1.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after Pixel editing")
+
+        # Now "edit" the VS but don't change it. We should still get the same values
+        self.controller.ReplaceResource(vsrefl.resourceId, nochangeVS)
+        self.controller.SetFrameEvent(eid, True)
+
+        # Triangles have green and blue channel
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 1.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after no-op vertex editing")
+
+        # Change the VS to one that has ofpset the triangles off-centre
+        self.controller.ReplaceResource(vsrefl.resourceId, offsetVS)
+        self.controller.SetFrameEvent(eid, True)
+
+        # Original sample positions are now the clear color
+        self.check_pixel_value(tex, 0.25, 0.5, [0.4, 0.5, 0.6, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.4, 0.5, 0.6, 1.0])
+
+        # Triangles have green and blue channel
+        self.check_pixel_value(tex, 0.45, 0.05, [0.0, 1.0, 1.0, 1.0])
+        self.check_pixel_value(tex, 0.95, 0.05, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after ofpset vertex editing")
+
+        # Now undo the first ps edit
+        self.controller.RemoveReplacement(psrefl1.resourceId)
+        self.controller.SetFrameEvent(eid, True)
+
+        # Original sample positions are still the clear color
+        self.check_pixel_value(tex, 0.25, 0.5, [0.4, 0.5, 0.6, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.4, 0.5, 0.6, 1.0])
+
+        # The right triangle is the edited colour, the other two have reverted to green channel only
+        self.check_pixel_value(tex, 0.45, 0.05, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.95, 0.05, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after removing first Pixel edit")
+
+        # Now undo the first VS edit
+        self.controller.RemoveReplacement(vsrefl.resourceId)
+        self.controller.SetFrameEvent(eid, True)
+
+        # The right triangle is the edited colour, but they are back in the original positions
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 1.0, 1.0])
+
+        rdtest.log.success("Values are as expected after removing vertex edit")
+
+        # finally undo the second ps edit
+        self.controller.RemoveReplacement(psrefl2.resourceId)
+        self.controller.SetFrameEvent(eid, True)
+
+        # We should be back to where we started
+        self.check_pixel_value(tex, 0.25, 0.5, [0.0, 1.0, 0.0, 1.0])
+        self.check_pixel_value(tex, 0.75, 0.5, [0.0, 1.0, 0.0, 1.0])
+
+        rdtest.log.success("Values are as expected after removing all edits")
+
+        self.controller.FreeTargetResource(nochangeVS)
+        self.controller.FreeTargetResource(offsetVS)
+        self.controller.FreeTargetResource(ps1)
+        self.controller.FreeTargetResource(ps2)