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I thought I would show some screenshots of my terrain engine. I''d like honest feedback. My question is, When water is in area and I draw the polygon representing it, the fps drop to 20 from 45. The water is just a gigantic pair of polygons. Is it actually better to draw a lot of smaller ones than 1 really big one? http://www.planetquake.com/tdk/index3.html

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First: Please add to that image a link to a large 800x600 or something sized screenshot. I cant stand gettn teased by thumbnails!!

Second: Please describe your terrain for me...
A) Do you use LOD of the terrain mesh? Like a roam, or adaptive quadtree to allow for high detail up close, less detail far away?
B) Do you "tile" your textures or is it 1 large texture for the area? Do you use mipmaps?
c) What did you use to create your terrain? (a grayscale height-value bitmap?)

Third(comments): Like i said, thumbnails suck, but from what I can see, it looks very very nice. It looks like you have a "campfire" light near that tent. If that was the intention, very nice touch. Your grass texturing looks good and so does the down-slope of your hill. I cant really see what the water looks like(that thumbnail again). Because the scene has low-lighting, i suggest having 2 pics: 1 in daytime, 1 at night. Why, because the textures seem a little dark so to get a real sense of them, daytime lighting would benifit in reviews!!!

Hope you dont mind all the questions. I have been gathering info on terrain engines myself. Any resources you can recommend??

Edited by - GalaxyQuest on January 2, 2002 2:31:54 PM

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A) It is not LOD at all.
B) Textures are tiled
C) I created a terrain editor where i can select the amount of earth to drag, then drag the height of the terrain up and down as a cube, spherical, inverted funnel or conical and soon will have a Sinc function. You can also smooth it out and erase it, and then you also draw the textures and place the models with adjustible sizes.

I must have the brightness on my monitor set too high because i considered the ss's as daylight :/

Edited by - Xanthen on January 2, 2002 3:52:07 PM

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I, like GQ even, have tried to make a terrain engine/level maker and have failed. I''m currently learning to render v38 IBSP''s because of it. Yes, they''re not nearly as good as a custom terrain engine but hey, gotta have some levels.

My point, how about writing up some info? A tutorial?
From what I can see, it looks very good and I know a lot of people would be interested in learning how you did it.

Just take your code, and comment the hell out of it making it a tutorial. =)

Just an idea.

Once again, it looks great!

- Mike

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This will have to do.

Some plain ground with my earth modifier


selected size then clicked and draged up.


Moved selector clicked and dragged down.


Sphere lifter selected now, clicked and dragged up.


Inverted funnel selected, made a bunch of em.


I now selected the smoother, heres some shots of it in progress




Now i''m satisfied so i draw on the ground with my texture applicator.


simple as that. Started on the terrain editor this past saturday.

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Your lil editor seems really neat. Nice job.

Would you be willing to answer a few more questions, that way I can try to figure this stuff out on my own without looking at code...i got a lot of questions!!

First:
What kind of method do you use to smooth?

Next(texture generation):
A) How large of an area does each texture cover?
B) When you are "spray painting" texture colors to a tile, how do you figure out which pixel color goes on which texture tile?

Next:
Do you use triangle strips/vertex arrays?

Last:
The map editing pics...is the map the size of what is on screen? What I am getting at is maps of very large size and whether you have thought of breaking them up. This way map chunks can be "paged" in on demand as you move around.

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To smooth I just took some height from one vertex and put it in the vertices all around it. Nothing special but it works well enough.

Texture covers whatever area you specify.

That next question has no bearing whatsoever on anything I do. In fact I can''t even understand what you were trying to ask

I use triangle strips.

The map is actually gigantic.
I mean really really gigantic. 1000 tiles wide 1000 tiles tall. A flat piece of ground you see about 20x20 tiles so thats 2500 DIFFERENT SCREEN FULLS. Actually its so absurdly large that it would take a level designer a year to fill it up. So obviously I will want to reduce its size tremendously but until It starts to slow down the processor theres no need. I get 45 fps running at 1280x1024 resolution with no objects loaded in the game and no water. But obviously if I have 4000 monsters then the map is gonna have to be smaller to perform the ai for that many things. So map size is only going to be limited to the amount of creatures in game.

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Ok, sorry if you didnt understand my question about "spraying".

What I was refering to is this, you said:
quote:
by Xanthen
Now i''m satisfied so i draw on the ground with my texture applicator.


To me, this can mean 2 different things. First is if you simply select a premade texture to be applied to that tile from file. The second idea, which is what I asked you about, would be to actually CREATE the texture right there by applying a type of "spray effect" similar to the spray can in paint programs. So, as you spray around the map, some of that color would be placed on adjacent tiles. This is where my question comes in. Sorry. Maybe I should just have asked if you simply select from a bunch of loaded textures the one you wish to place on a single tile...hehe...oh well.

I tend to make things a lil tuff on myself.

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I use a premade texture and apply it to the tile

Actually constructive feedback would be prefered.
not just oh it looks nice or what not.

Edited by - Xanthen on January 2, 2002 9:18:16 PM

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Ok. Your water looks very tiled. It is also too transparent. Even in the blown up screenshot i cant tell how deep the water is suppose to be, so I can only guess as to the deepness. So, unless it is a shallow stream, you normally dont see the bottom.

From the look of it, you seem to tile your graphics well(i dont see really apparent edges), except for the water, which looks bad.

The lighting isnt too great either. Is it daytime? Im not sure if you mentioned if you had lighting in it or not. If not, that is somethin you can work twiddled.

Also, I think your asking for deeper critism that is simply hard to just give out after just looking at a few screenshots. Not to mention that I have been the one who has to ask you many questions just to get the info on what is going on. Make a webpage describing how you made this, what techniques you use for texturing, the height mesh, lighing, shadow effects, blah blah blah...we could have gone straight into critism if you had this stuff, so there you have it. :/

Edited by - GalaxyQuest on January 2, 2002 11:36:09 PM

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Typically you don''t need to know how an engine works to know what looks good and what doesn''t. But yes I know the water sucks, I just got it in yesterday and the artist guy is finishing up a different project before he starts helpin me so all the artwork is just temporary stuff. And the transparency on it is temporary as well.
But yes now that you mention it, My lightning does need some serious attention. For some reason I hadn''t noticed how.... far off it is.

Hahah, looking at the editor shots I showed I see how truely horrible it is. I was just doing a vertex normal and doing a crossproduct with a verticle for sun, but I guess thats not the way to do it.

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The water appears to be the only transparent texture, so it seems clear to me that the transparency is what's slowing you down. Make it opaque and you should see the framerate increase.

As for lightning, I found gouraud shading to work very well. I just calculate the light color for each vertex in software, and have OpenGL use gouraud shading.

You can download mine to see it, I have a sun and moon that rise and set... they're not drawn but the lighting for them is calculated.

The controls are W/S to walk forward/backwards, A/D to strafe left/right, and the mouse to look around. F5 toggles wireframe on/off, F6 switches between gouraud and flat shading, and F7 toggles on/off texture linear interpolation.

There are optional command line parameters. Here they are:
/size 640x480
/size 800x600
/size 1024x768
/size 1280x960
/bitdepth 16
/bitdepth 32
/zbitdepth 16
/zbitdepth 24
/mode window
/mode fullscreen

Here's the link: www.geocities.com/cgamedude/Vista.zip

~CGameProgrammer( );



Edited by - CGameProgrammer on January 3, 2002 1:57:31 PM

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Also logically speaking. For the polygon count of your water...

A quad/2 triangles should work, unless you wish to animate it with waves etc... Then you will have to break it down to smaller polys to make smoothe waves...

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CGameProgrammer:

Loaded your example, but, oddly, polygons kept popping up and down... some sort of bug? (a couple times I saw large pyramids taller than the hills rising from the valleys and falling again with a subtle change of direction...)

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quote:
Original post by quarnin
CGameProgrammer:

Loaded your example, but, oddly, polygons kept popping up and down... some sort of bug? (a couple times I saw large pyramids taller than the hills rising from the valleys and falling again with a subtle change of direction...)



I didn''t have that problem at all.
It runs very smooth and the terrain is the same.

Athlon 900, Radeon64 DDR, 256MB RAM. *shrugs*

- Mike

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Guest Anonymous Poster
I''m guessing it has something to do with his LOD technique and your computer. I get the same problem, though not as severe as you are describing it.

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      ShaderCreationAttribs Attrs; Attrs.Desc.Name = "MyPixelShader"; Attrs.FilePath = "MyShaderFile.fx"; Attrs.SearchDirectories = "shaders;shaders\\inc;"; Attrs.EntryPoint = "MyPixelShader"; Attrs.Desc.ShaderType = SHADER_TYPE_PIXEL; Attrs.SourceLanguage = SHADER_SOURCE_LANGUAGE_HLSL; BasicShaderSourceStreamFactory BasicSSSFactory(Attrs.SearchDirectories); Attrs.pShaderSourceStreamFactory = &BasicSSSFactory; ShaderVariableDesc ShaderVars[] = {     {"g_StaticTexture", SHADER_VARIABLE_TYPE_STATIC},     {"g_MutableTexture", SHADER_VARIABLE_TYPE_MUTABLE},     {"g_DynamicTexture", SHADER_VARIABLE_TYPE_DYNAMIC} }; Attrs.Desc.VariableDesc = ShaderVars; Attrs.Desc.NumVariables = _countof(ShaderVars); Attrs.Desc.DefaultVariableType = SHADER_VARIABLE_TYPE_STATIC; StaticSamplerDesc StaticSampler; StaticSampler.Desc.MinFilter = FILTER_TYPE_LINEAR; StaticSampler.Desc.MagFilter = FILTER_TYPE_LINEAR; StaticSampler.Desc.MipFilter = FILTER_TYPE_LINEAR; StaticSampler.TextureName = "g_MutableTexture"; Attrs.Desc.NumStaticSamplers = 1; Attrs.Desc.StaticSamplers = &StaticSampler; ShaderMacroHelper Macros; Macros.AddShaderMacro("USE_SHADOWS", 1); Macros.AddShaderMacro("NUM_SHADOW_SAMPLES", 4); Macros.Finalize(); Attrs.Macros = Macros; RefCntAutoPtr<IShader> pShader; m_pDevice->CreateShader( Attrs, &pShader );
      Creating the Pipeline State Object
      After all required shaders are created, the rest of the fields of the PipelineStateDesc structure provide depth-stencil, rasterizer, and blend state descriptions, the number and format of render targets, input layout format, etc. For instance, rasterizer state can be described as follows:
      PipelineStateDesc PSODesc; RasterizerStateDesc &RasterizerDesc = PSODesc.GraphicsPipeline.RasterizerDesc; RasterizerDesc.FillMode = FILL_MODE_SOLID; RasterizerDesc.CullMode = CULL_MODE_NONE; RasterizerDesc.FrontCounterClockwise = True; RasterizerDesc.ScissorEnable = True; RasterizerDesc.AntialiasedLineEnable = False; Depth-stencil and blend states are defined in a similar fashion.
      Another important thing that pipeline state object encompasses is the input layout description that defines how inputs to the vertex shader, which is the very first shader stage, should be read from the memory. Input layout may define several vertex streams that contain values of different formats and sizes:
      // Define input layout InputLayoutDesc &Layout = PSODesc.GraphicsPipeline.InputLayout; LayoutElement TextLayoutElems[] = {     LayoutElement( 0, 0, 3, VT_FLOAT32, False ),     LayoutElement( 1, 0, 4, VT_UINT8, True ),     LayoutElement( 2, 0, 2, VT_FLOAT32, False ), }; Layout.LayoutElements = TextLayoutElems; Layout.NumElements = _countof( TextLayoutElems ); Finally, pipeline state defines primitive topology type. When all required members are initialized, a pipeline state object can be created by IRenderDevice::CreatePipelineState() method:
      // Define shader and primitive topology PSODesc.GraphicsPipeline.PrimitiveTopologyType = PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE; PSODesc.GraphicsPipeline.pVS = pVertexShader; PSODesc.GraphicsPipeline.pPS = pPixelShader; PSODesc.Name = "My pipeline state"; m_pDev->CreatePipelineState(PSODesc, &m_pPSO); When PSO object is bound to the pipeline, the engine invokes all API-specific commands to set all states specified by the object. In case of Direct3D12 this maps directly to setting the D3D12 PSO object. In case of Direct3D11, this involves setting individual state objects (such as rasterizer and blend states), shaders, input layout etc. In case of OpenGL, this requires a number of fine-grain state tweaking calls. Diligent Engine keeps track of currently bound states and only calls functions to update these states that have actually changed.
      Binding Shader Resources
      Direct3D11 and OpenGL utilize fine-grain resource binding models, where an application binds individual buffers and textures to certain shader or program resource binding slots. Direct3D12 uses a very different approach, where resource descriptors are grouped into tables, and an application can bind all resources in the table at once by setting the table in the command list. Resource binding model in Diligent Engine is designed to leverage this new method. It introduces a new object called shader resource binding that encapsulates all resource bindings required for all shaders in a certain pipeline state. It also introduces the classification of shader variables based on the frequency of expected change that helps the engine group them into tables under the hood:
      Static variables (SHADER_VARIABLE_TYPE_STATIC) are variables that are expected to be set only once. They may not be changed once a resource is bound to the variable. Such variables are intended to hold global constants such as camera attributes or global light attributes constant buffers. Mutable variables (SHADER_VARIABLE_TYPE_MUTABLE) define resources that are expected to change on a per-material frequency. Examples may include diffuse textures, normal maps etc. Dynamic variables (SHADER_VARIABLE_TYPE_DYNAMIC) are expected to change frequently and randomly. Shader variable type must be specified during shader creation by populating an array of ShaderVariableDesc structures and initializing ShaderCreationAttribs::Desc::VariableDesc and ShaderCreationAttribs::Desc::NumVariables members (see example of shader creation above).
      Static variables cannot be changed once a resource is bound to the variable. They are bound directly to the shader object. For instance, a shadow map texture is not expected to change after it is created, so it can be bound directly to the shader:
      PixelShader->GetShaderVariable( "g_tex2DShadowMap" )->Set( pShadowMapSRV ); Mutable and dynamic variables are bound via a new Shader Resource Binding object (SRB) that is created by the pipeline state (IPipelineState::CreateShaderResourceBinding()):
      m_pPSO->CreateShaderResourceBinding(&m_pSRB); Note that an SRB is only compatible with the pipeline state it was created from. SRB object inherits all static bindings from shaders in the pipeline, but is not allowed to change them.
      Mutable resources can only be set once for every instance of a shader resource binding. Such resources are intended to define specific material properties. For instance, a diffuse texture for a specific material is not expected to change once the material is defined and can be set right after the SRB object has been created:
      m_pSRB->GetVariable(SHADER_TYPE_PIXEL, "tex2DDiffuse")->Set(pDiffuseTexSRV); In some cases it is necessary to bind a new resource to a variable every time a draw command is invoked. Such variables should be labeled as dynamic, which will allow setting them multiple times through the same SRB object:
      m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "cbRandomAttribs")->Set(pRandomAttrsCB); Under the hood, the engine pre-allocates descriptor tables for static and mutable resources when an SRB objcet is created. Space for dynamic resources is dynamically allocated at run time. Static and mutable resources are thus more efficient and should be used whenever possible.
      As you can see, Diligent Engine does not expose low-level details of how resources are bound to shader variables. One reason for this is that these details are very different for various APIs. The other reason is that using low-level binding methods is extremely error-prone: it is very easy to forget to bind some resource, or bind incorrect resource such as bind a buffer to the variable that is in fact a texture, especially during shader development when everything changes fast. Diligent Engine instead relies on shader reflection system to automatically query the list of all shader variables. Grouping variables based on three types mentioned above allows the engine to create optimized layout and take heavy lifting of matching resources to API-specific resource location, register or descriptor in the table.
      This post gives more details about the resource binding model in Diligent Engine.
      Setting the Pipeline State and Committing Shader Resources
      Before any draw or compute command can be invoked, the pipeline state needs to be bound to the context:
      m_pContext->SetPipelineState(m_pPSO); Under the hood, the engine sets the internal PSO object in the command list or calls all the required native API functions to properly configure all pipeline stages.
      The next step is to bind all required shader resources to the GPU pipeline, which is accomplished by IDeviceContext::CommitShaderResources() method:
      m_pContext->CommitShaderResources(m_pSRB, COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES); The method takes a pointer to the shader resource binding object and makes all resources the object holds available for the shaders. In the case of D3D12, this only requires setting appropriate descriptor tables in the command list. For older APIs, this typically requires setting all resources individually.
      Next-generation APIs require the application to track the state of every resource and explicitly inform the system about all state transitions. For instance, if a texture was used as render target before, while the next draw command is going to use it as shader resource, a transition barrier needs to be executed. Diligent Engine does the heavy lifting of state tracking.  When CommitShaderResources() method is called with COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES flag, the engine commits and transitions resources to correct states at the same time. Note that transitioning resources does introduce some overhead. The engine tracks state of every resource and it will not issue the barrier if the state is already correct. But checking resource state is an overhead that can sometimes be avoided. The engine provides IDeviceContext::TransitionShaderResources() method that only transitions resources:
      m_pContext->TransitionShaderResources(m_pPSO, m_pSRB); In some scenarios it is more efficient to transition resources once and then only commit them.
      Invoking Draw Command
      The final step is to set states that are not part of the PSO, such as render targets, vertex and index buffers. Diligent Engine uses Direct3D11-syle API that is translated to other native API calls under the hood:
      ITextureView *pRTVs[] = {m_pRTV}; m_pContext->SetRenderTargets(_countof( pRTVs ), pRTVs, m_pDSV); // Clear render target and depth buffer const float zero[4] = {0, 0, 0, 0}; m_pContext->ClearRenderTarget(nullptr, zero); m_pContext->ClearDepthStencil(nullptr, CLEAR_DEPTH_FLAG, 1.f); // Set vertex and index buffers IBuffer *buffer[] = {m_pVertexBuffer}; Uint32 offsets[] = {0}; Uint32 strides[] = {sizeof(MyVertex)}; m_pContext->SetVertexBuffers(0, 1, buffer, strides, offsets, SET_VERTEX_BUFFERS_FLAG_RESET); m_pContext->SetIndexBuffer(m_pIndexBuffer, 0); Different native APIs use various set of function to execute draw commands depending on command details (if the command is indexed, instanced or both, what offsets in the source buffers are used etc.). For instance, there are 5 draw commands in Direct3D11 and more than 9 commands in OpenGL with something like glDrawElementsInstancedBaseVertexBaseInstance not uncommon. Diligent Engine hides all details with single IDeviceContext::Draw() method that takes takes DrawAttribs structure as an argument. The structure members define all attributes required to perform the command (primitive topology, number of vertices or indices, if draw call is indexed or not, if draw call is instanced or not, if draw call is indirect or not, etc.). For example:
      DrawAttribs attrs; attrs.IsIndexed = true; attrs.IndexType = VT_UINT16; attrs.NumIndices = 36; attrs.Topology = PRIMITIVE_TOPOLOGY_TRIANGLE_LIST; pContext->Draw(attrs); For compute commands, there is IDeviceContext::DispatchCompute() method that takes DispatchComputeAttribs structure that defines compute grid dimension.
      Source Code
      Full engine source code is available on GitHub and is free to use. The repository contains two samples, asteroids performance benchmark and example Unity project that uses Diligent Engine in native plugin.
      AntTweakBar sample is Diligent Engine’s “Hello World” example.

       
      Atmospheric scattering sample is a more advanced example. It demonstrates how Diligent Engine can be used to implement various rendering tasks: loading textures from files, using complex shaders, rendering to multiple render targets, using compute shaders and unordered access views, etc.

      Asteroids performance benchmark is based on this demo developed by Intel. It renders 50,000 unique textured asteroids and allows comparing performance of Direct3D11 and Direct3D12 implementations. Every asteroid is a combination of one of 1000 unique meshes and one of 10 unique textures.

      Finally, there is an example project that shows how Diligent Engine can be integrated with Unity.

      Future Work
      The engine is under active development. It currently supports Windows desktop, Universal Windows and Android platforms. Direct3D11, Direct3D12, OpenGL/GLES backends are now feature complete. Vulkan backend is coming next, and support for more platforms is planned.
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