• Advertisement
  • Popular Tags

  • Popular Now

  • Advertisement
  • Similar Content

    • By cozzie
      Hi all,
      As a part of the debug drawing system in my engine,  I want to add support for rendering simple text on screen  (aka HUD/ HUD style). From what I've read there are a few options, in short:
      1. Write your own font sprite renderer
      2. Using Direct2D/Directwrite, combine with DX11 rendertarget/ backbuffer
      3. Use an external library, like the directx toolkit etc.
      I want to go for number 2, but articles/ documentation confused me a bit. Some say you need to create a DX10 device, to be able to do this, because it doesn't directly work with the DX11 device.  But other articles tell that this was 'patched' later on and should work now.
      Can someone shed some light on this and ideally provide me an example or article on  how to set this up?
      All input is appreciated.
    • By stale
      I've just started learning about tessellation from Frank Luna's DX11 book. I'm getting some very weird behavior when I try to render a tessellated quad patch if I also render a mesh in the same frame. The tessellated quad patch renders just fine if it's the only thing I'm rendering. This is pictured below:
      However, when I attempt to render the same tessellated quad patch along with the other entities in the scene (which are simple triangle-lists), I get the following error:

      I have no idea why this is happening, and google searches have given me no leads at all. I use the following code to render the tessellated quad patch:
      ID3D11DeviceContext* dc = GetGFXDeviceContext(); dc->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_4_CONTROL_POINT_PATCHLIST); dc->IASetInputLayout(ShaderManager::GetInstance()->m_JQuadTess->m_InputLayout); float blendFactors[] = { 0.0f, 0.0f, 0.0f, 0.0f }; // only used with D3D11_BLEND_BLEND_FACTOR dc->RSSetState(m_rasterizerStates[RSWIREFRAME]); dc->OMSetBlendState(m_blendStates[BSNOBLEND], blendFactors, 0xffffffff); dc->OMSetDepthStencilState(m_depthStencilStates[DSDEFAULT], 0); ID3DX11EffectTechnique* activeTech = ShaderManager::GetInstance()->m_JQuadTess->Tech; D3DX11_TECHNIQUE_DESC techDesc; activeTech->GetDesc(&techDesc); for (unsigned int p = 0; p < techDesc.Passes; p++) { TerrainVisual* terrainVisual = (TerrainVisual*)entity->m_VisualComponent; UINT stride = sizeof(TerrainVertex); UINT offset = 0; GetGFXDeviceContext()->IASetVertexBuffers(0, 1, &terrainVisual->m_VB, &stride, &offset); Vector3 eyePos = Vector3(cam->m_position); Matrix rotation = Matrix::CreateFromYawPitchRoll(entity->m_rotationEuler.x, entity->m_rotationEuler.y, entity->m_rotationEuler.z); Matrix model = rotation * Matrix::CreateTranslation(entity->m_position); Matrix view = cam->GetLookAtMatrix(); Matrix MVP = model * view * m_ProjectionMatrix; ShaderManager::GetInstance()->m_JQuadTess->SetEyePosW(eyePos); ShaderManager::GetInstance()->m_JQuadTess->SetWorld(model); ShaderManager::GetInstance()->m_JQuadTess->SetWorldViewProj(MVP); activeTech->GetPassByIndex(p)->Apply(0, GetGFXDeviceContext()); GetGFXDeviceContext()->Draw(4, 0); } dc->RSSetState(0); dc->OMSetBlendState(0, blendFactors, 0xffffffff); dc->OMSetDepthStencilState(0, 0); I draw my scene by looping through the list of entities and calling the associated draw method depending on the entity's "visual type":
      for (unsigned int i = 0; i < scene->GetEntityList()->size(); i++) { Entity* entity = scene->GetEntityList()->at(i); if (entity->m_VisualComponent->m_visualType == VisualType::MESH) DrawMeshEntity(entity, cam, sun, point); else if (entity->m_VisualComponent->m_visualType == VisualType::BILLBOARD) DrawBillboardEntity(entity, cam, sun, point); else if (entity->m_VisualComponent->m_visualType == VisualType::TERRAIN) DrawTerrainEntity(entity, cam); } HR(m_swapChain->Present(0, 0)); Any help/advice would be much appreciated!
    • By KaiserJohan
      Am trying a basebones tessellation shader and getting unexpected result when increasing the tessellation factor. Am rendering a group of quads and trying to apply tessellation to them.
      OutsideTess = (1,1,1,1), InsideTess= (1,1)

      OutsideTess = (1,1,1,1), InsideTess= (2,1)

      I expected 4 triangles in the quad, not two. Any idea of whats wrong?
      struct PatchTess { float mEdgeTess[4] : SV_TessFactor; float mInsideTess[2] : SV_InsideTessFactor; }; struct VertexOut { float4 mWorldPosition : POSITION; float mTessFactor : TESS; }; struct DomainOut { float4 mWorldPosition : SV_POSITION; }; struct HullOut { float4 mWorldPosition : POSITION; }; Hull shader:
      PatchTess PatchHS(InputPatch<VertexOut, 3> inputVertices) { PatchTess patch; patch.mEdgeTess[ 0 ] = 1; patch.mEdgeTess[ 1 ] = 1; patch.mEdgeTess[ 2 ] = 1; patch.mEdgeTess[ 3 ] = 1; patch.mInsideTess[ 0 ] = 2; patch.mInsideTess[ 1 ] = 1; return patch; } [domain("quad")] [partitioning("fractional_odd")] [outputtopology("triangle_ccw")] [outputcontrolpoints(4)] [patchconstantfunc("PatchHS")] [maxtessfactor( 64.0 )] HullOut hull_main(InputPatch<VertexOut, 3> verticeData, uint index : SV_OutputControlPointID) { HullOut ret; ret.mWorldPosition = verticeData[index].mWorldPosition; return ret; }  
      Domain shader:
      [domain("quad")] DomainOut domain_main(PatchTess patchTess, float2 uv : SV_DomainLocation, const OutputPatch<HullOut, 4> quad) { DomainOut ret; const float MipInterval = 20.0f; ret.mWorldPosition.xz = quad[ 0 ].mWorldPosition.xz * ( 1.0f - uv.x ) * ( 1.0f - uv.y ) + quad[ 1 ].mWorldPosition.xz * uv.x * ( 1.0f - uv.y ) + quad[ 2 ].mWorldPosition.xz * ( 1.0f - uv.x ) * uv.y + quad[ 3 ].mWorldPosition.xz * uv.x * uv.y ; ret.mWorldPosition.y = quad[ 0 ].mWorldPosition.y; ret.mWorldPosition.w = 1; ret.mWorldPosition = mul( gFrameViewProj, ret.mWorldPosition ); return ret; }  
      Any ideas what could be wrong with these shaders?
    • By simco50
      I've stumbled upon Urho3D engine and found that it has a really nice and easy to read code structure.
      I think the graphics abstraction looks really interesting and I like the idea of how it defers pipeline state changes until just before the draw call to resolve redundant state changes.
      This is done by saving the state changes (blendEnabled/SRV changes/RTV changes) in member variables and just before the draw, apply the actual state changes using the graphics context.
      It looks something like this (pseudo):
      void PrepareDraw() { if(renderTargetsDirty) { pD3D11DeviceContext->OMSetRenderTarget(mCurrentRenderTargets); renderTargetsDirty = false } if(texturesDirty) { pD3D11DeviceContext->PSSetShaderResourceView(..., mCurrentSRVs); texturesDirty = false } .... //Some more state changes } This all looked like a great design at first but I've found that there is one big issue with this which I don't really understand how it is solved in their case and how I would tackle it.
      I'll explain it by example, imagine I have two rendertargets: my backbuffer RT and an offscreen RT.
      Say I want to render my backbuffer to the offscreen RT and then back to the backbuffer (Just for the sake of the example).
      You would do something like this:
      //Render to the offscreen RT pGraphics->SetRenderTarget(pOffscreenRT->GetRTV()); pGraphics->SetTexture(diffuseSlot, pDefaultRT->GetSRV()) pGraphics->DrawQuad() pGraphics->SetTexture(diffuseSlot, nullptr); //Remove the default RT from input //Render to the default (screen) RT pGraphics->SetRenderTarget(nullptr); //Default RT pGraphics->SetTexture(diffuseSlot, pOffscreenRT->GetSRV()) pGraphics->DrawQuad(); The problem here is that the second time the application loop comes around, the offscreen rendertarget is still bound as input ShaderResourceView when it gets set as a RenderTargetView because in Urho3D, the state of the RenderTargetView will always be changed before the ShaderResourceViews (see top code snippet) even when I set the SRV to nullptr before using it as a RTV like above causing errors because a resource can't be bound to both input and rendertarget.
      What is usually the solution to this?
    • By MehdiUBP
      I wrote a MatCap shader following this idea:
      Given the image representing the texture, we compute the sample point by taking the dot product of the vertex normal and the camera position and remapping this to [0,1].
      This seems to work well when I look straight at an object with this shader. However, in cases where the camera points slightly on the side, I can see the texture stretch a lot.
      Could anyone give me a hint as how to get a nice matcap shader ?
      Here's what I wrote:
      Shader "Unlit/Matcap"
              _MainTex ("Texture", 2D) = "white" {}
              Tags { "RenderType"="Opaque" }
              LOD 100
                  #pragma vertex vert
                  #pragma fragment frag
                  // make fog work
                  #include "UnityCG.cginc"
                  struct appdata
                      float4 vertex : POSITION;
                      float3 normal : NORMAL;
                  struct v2f
                      float2 worldNormal : TEXCOORD0;
                      float4 vertex : SV_POSITION;
                  sampler2D _MainTex;            
                  v2f vert (appdata v)
                      v2f o;
                      o.vertex = UnityObjectToClipPos(v.vertex);
                      o.worldNormal = mul((float3x3)UNITY_MATRIX_V, UnityObjectToWorldNormal(v.normal)).xy*0.3 + 0.5;  //UnityObjectToClipPos(v.normal)*0.5 + 0.5;
                      return o;
                  fixed4 frag (v2f i) : SV_Target
                      // sample the texture
                      fixed4 col = tex2D(_MainTex, i.worldNormal);
                      // apply fog
                      return col;
  • Advertisement
  • Advertisement
Sign in to follow this  

DX11 Instancing

This topic is 2214 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts


I have been following this tutorial , but while experimenting I reached a dead end. The addition I was trying to implement is a dynamic updating rotation per instance.

So first, i define

// TriangleTest.h
struct InstanceType
D3DXVECTOR3 position;
D3DXVECTOR3 rotation;

for my Instance buffer Type, which leads me to define

// vertexshader.vs
struct VertexInputType
float3 position : POSITION;
float4 color : COLOR;
float3 instancePosition : POSITION1;
float3 instanceRotation : POSITION2;

in my vertex Shader file. Note that I have changed the usage of semantic type TEXCOORD from the tutorial, as I feel more comfortable having positions use POSITION, as well as giving the position a float3 type.

I set up my InputElementDescription array like this

polygonLayout[0].SemanticName = "POSITION";
polygonLayout[0].SemanticIndex = 0;
polygonLayout[0].Format = DXGI_FORMAT_R32G32B32_FLOAT;
polygonLayout[0].InputSlot = 0;
polygonLayout[0].AlignedByteOffset = 0;
polygonLayout[0].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[0].InstanceDataStepRate = 0;
polygonLayout[1].SemanticName = "COLOR";
polygonLayout[1].SemanticIndex = 0;
polygonLayout[1].Format = DXGI_FORMAT_R32G32B32A32_FLOAT;
polygonLayout[1].InputSlot = 0;
polygonLayout[1].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
polygonLayout[1].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
polygonLayout[1].InstanceDataStepRate = 0;
polygonLayout[2].SemanticName = "POSITION";
polygonLayout[2].SemanticIndex = 1;
polygonLayout[2].Format = DXGI_FORMAT_R32G32B32_FLOAT;
polygonLayout[2].InputSlot = 1;
polygonLayout[2].AlignedByteOffset = 0;
polygonLayout[2].InputSlotClass = D3D11_INPUT_PER_INSTANCE_DATA;
polygonLayout[2].InstanceDataStepRate = 1;
polygonLayout[3].SemanticName = "POSITION";
polygonLayout[3].SemanticIndex = 2;
polygonLayout[3].Format = DXGI_FORMAT_R32G32B32_FLOAT;
polygonLayout[3].InputSlot = 1;
polygonLayout[3].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
polygonLayout[3].InputSlotClass = D3D11_INPUT_PER_INSTANCE_DATA;
polygonLayout[3].InstanceDataStepRate = 1;

and create the input layouts.
In my model class (TriangeTest), i use this to update the dynamic instance buffer ( completely created as D3D11_USAGE_DYNAMIC, with D3D11_CP_ACCESS_WRITE)

void TriangleTest::Frame(ID3D11DeviceContext* deviceContext) {
for (int i = 0; i < this->i_instanceCount; i++) {
D3DXVec3Add(&(m_instanceList.rotation), &(m_instanceList.rotation), &D3DXVECTOR3(1,0,0.0f));
void TriangleTest::UpdateBuffers(ID3D11DeviceContext* deviceContext) {
HRESULT result;
D3D11_MAPPED_SUBRESOURCE mappedResource;
InstanceType* instancePtr;

result =deviceContext->Map(m_instanceBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mappedResource);
if(FAILED(result)) throw CException("Could not remap instance buffer");
instancePtr = (InstanceType*)mappedResource.pData;
memcpy(instancePtr, (void*)m_instanceList, (sizeof(InstanceType) * i_instanceCount));
deviceContext->Unmap(m_instanceBuffer, 0);

, where m_instanceList is an array of InstanceType holding all information on the position and rotation per triangle. Of course, theFrame(...) function gets called once per frame.

Then I use the shader as provided and replace instancePosition with instanceRotation,which should make my triangles slide out to the right.

PixelInputType TextureVertexShader(VertexInputType input)
PixelInputType output;

// Change the position vector to be 4 units for proper matrix calculations.
input.position.w = 1.0f;
Here is where we use the instanced position information to modify the position of each triangle we are drawing.
// Update the position of the vertices based on the data for this particular instance.
input.position.x += input.instanceRotation.x;
input.position.y += input.instanceRotation.y;
input.position.z += input.instanceRotation.z;
// Calculate the position of the vertex against the world, view, and projection matrices.
output.position = mul(input.position, worldMatrix);
output.position = mul(output.position, viewMatrix);
output.position = mul(output.position, projectionMatrix);

// Store the texture coordinates for the pixel shader.
output.tex = input.tex;

return output;

But when I run it (complete without errors), the triangles stay still on the screen. Even when using instancePosition again. They move however, if I change the semantic type of inputPosition to TEXCOORD and update the position in the Frame procedure, but even then I get no motion from the instanceRotation.

Which leads me to think, that my InputElementLayoutDescription is wrong. But how? I have tried many a combination already, but don't understand.

Can anyone enlighten me with their ideas?

Share this post

Link to post
Share on other sites
I'm taking a bit of a guess here but it might be because your first semantic usage of POSITION is not POSITION0 (zero) which is causing the binding to fail for some reason; try giving it the semantic POSITION0 and see if that helps.

Share this post

Link to post
Share on other sites
That actually did the trick.
Thank you so very much, i thought I had tried this before, but my mind was so messed up with this, I screwed it completely and tested it with some update code disabled. I was already going to tell you how it doesn't work, but kept trying once more to consider your answer, and Voila.

It actually works.

Share this post

Link to post
Share on other sites
Sign in to follow this  

  • Advertisement