• 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 Mip map initialisation

This topic is 1993 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

So my adventures in D3D11 continue. I am struggling to understand how mipmapping works. In this project I am also trying not to depend on D3DX11 so I am creating textures programmatically. However I am struggling to understand how the mip map generation works. Here's how I create a texture (minus error checking etc)

DWORD* loaded_data; // loaded using FreeImage

uint width = FreeImage_GetWidth(image32);
uint height = FreeImage_GetHeight(image32);
uint mips = GetNumMipLevels(width, height);
Desc.Width = width;
Desc.Height = height;
Desc.MipLevels = mips; // auto-generates the whole chain
Desc.MiscFlags = 0;
Desc.ArraySize = 1;
Desc.CPUAccessFlags = 0;
Desc.SampleDesc.Count = 1;
Desc.SampleDesc.Quality = 0;

D3D11_SUBRESOURCE_DATA* initialData = new D3D11_SUBRESOURCE_DATA[mips];

for (uint i = 0; i < mips; i++)
uint mip = (uint)powf(2.f, (float)i);
initialData.pSysMem = loaded_data;
initialData.SysMemPitch = width * 4;
initialData.SysMemSlicePitch = width * height * 4;

pDevice->pDevice->CreateTexture2D(&Desc, initialData, &pTexture);
delete[] initialData;

ZeroMemory(&viewDesc, sizeof(D3D11_SHADER_RESOURCE_VIEW_DESC));
viewDesc.Format = Desc.Format;
viewDesc.Texture2D.MipLevels = -1;
viewDesc.Texture2D.MostDetailedMip = 0;
viewDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;

pDevice->pDevice->CreateShaderResourceView(pTexture, &viewDesc, &pView);

return S_OK;

However I don't think this is generating the mip maps correctly, or they aren't being used. Look at the left of the cube in this screenshot

Uploaded with ImageShack.us

I dont think the sampler is at fault, but just in case, it is set up like this

desc.AddressV = desc.AddressU;
desc.AddressW = desc.AddressU;
desc.BorderColor[0] = desc.BorderColor[1] = desc.BorderColor[2] = desc.BorderColor[3] = 1.0f;
desc.ComparisonFunc = D3D11_COMPARISON_NEVER;
desc.MaxAnisotropy = 0;
desc.MaxLOD = 0;
desc.MinLOD = 0;
desc.MipLODBias = 0.0f;

So can anyone see what I'm doing wrong?

Share this post

Link to post
Share on other sites
The way you're trying to do things would require that you have the mipmap data already generated when you created the function. There is no "automatic" mip generation for IMMUTABLE textures, since they require that you pass all of the required data to it. What you're actually doing in your code is you're passing the top-level mip data to all of the lower-resolution mip levels, which isn't right. If you do have all of the mips generated, then for each D3D11_SUBRESOURCE_DATA you need to have it point to the data for that mip. You would also need to set the proper pitch for that mip level, which get smaller as you go up in the levels.

If you don't actually have the mips generated and you want them to be generated by the hardware, you need to set it up differently. Here's an example of how to do it, taken from the WICTextureLoader sampler from DirectXTex:

// Create texture
desc.Width = twidth;
desc.Height = theight;
desc.MipLevels = (autogen) ? 0 : 1;
desc.ArraySize = 1;
desc.Format = format;
desc.SampleDesc.Count = 1;
desc.SampleDesc.Quality = 0;
desc.Usage = D3D11_USAGE_DEFAULT;
desc.CPUAccessFlags = 0;
desc.MiscFlags = (autogen) ? D3D11_RESOURCE_MISC_GENERATE_MIPS : 0;
initData.pSysMem = temp.get();
initData.SysMemPitch = static_cast<UINT>( rowPitch );
initData.SysMemSlicePitch = static_cast<UINT>( imageSize );
ID3D11Texture2D* tex = nullptr;
hr = d3dDevice->CreateTexture2D( &desc, (autogen) ? nullptr : &initData, &tex );
if ( SUCCEEDED(hr) && tex != 0 )
if (textureView != 0)
memset( &SRVDesc, 0, sizeof( SRVDesc ) );
SRVDesc.Format = format;
SRVDesc.Texture2D.MipLevels = (autogen) ? -1 : 1;
hr = d3dDevice->CreateShaderResourceView( tex, &SRVDesc, textureView );
if ( FAILED(hr) )
return hr;
if ( autogen )
assert( d3dContext != 0 );
d3dContext->UpdateSubresource( tex, 0, nullptr, temp.get(), static_cast<UINT>(rowPitch), static_cast<UINT>(imageSize) );
d3dContext->GenerateMips( *textureView );

Share this post

Link to post
Share on other sites
Sorry to bump such an old thread. I would like to say, thanks for the help MJP, and it has been solved as you said. FreeImage has image resize functions which made it very quick and easy, and they support a variety of filters as well, which is great.

I have another question about this method though. It appears that you are marking it for default usage and as a potential render target.
Surely there is a performance hit for this?

(I thought that if the texture is IMMUTABLE on some cards it goes in a different texture memory that the hardware can access faster. However if not then this is doubly excellent, not only is texture generation likely to be much faster due to GPU mip map generation, but all textures can be render targets, so I could have super fast bullet holes and decals!)

I am also bumping to point out that the sampler is in fact incorrectly set up. As the MinLOD and MaxLOD members are both set to 0, this forces the sampler to use only the most detailed mip, which of course is wrong. The correct sampler state is as above, with:

desc.MaxLOD = D3D11_FLOAT32_MAX; // or simply FLT_MAX
desc.MinLOD = 0;

Share this post

Link to post
Share on other sites
It's possible that using default usage and render target binding could cause different behavior for a texture, but that's completely dependent on the hardware and the driver. Your best bet for GPU performance is to use IMMUTABLE, since that guaranteed that the driver will put the texture in the best possible memory location with the best possible memory layout for that use case.

Share this post

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

  • Advertisement