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Xeeynamo

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About Xeeynamo

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  1. List of classes

    That code doesn't work because I'm using C++03.  Meanwhile I tried to find a solution and seems that finally I found it! http://pastebin.com/Ngntpevu I copied the pointer of A::Create and B::Create in the array and I call them when necessary. But the problems doesn't ends here, this works with MinGW compiler, but not with MVCPP one. The error is C2440: 'IObject *(__thiscall A::* )(void)' to 'IObject *(__thiscall *)(void)'
  2. I know that maybe it's not the proper title, but I have some difficulties to understand how to explain the problem in a short line. Basically I'm creating a framework with an high level of abstraction. I'm searching a decent way to create an initialization part where I describe how every object should works and a way to get that description to create the object from the index specified. I need to create some complex objects with the same structure but with different attributes. I have found a way but it seems not efficient: #include <stdio.h> class IObject { public: virtual IObject* Create() = 0; virtual void Main() = 0; }; class A : public IObject { public: IObject* Create() { return new A; } void Main() { printf("A"); } }; class B : public IObject { public: IObject* Create() { return new B; } void Main() { printf("B"); } }; size_t objCount = 0; IObject* objList[0x10]; void AddObject(IObject* o) { objList[objCount++] = o; } void RemoveAllObjects() { while(objCount) delete objList[--objCount]; } IObject* CreateObject(int index) { return objList[index]->Create(); } void Main() { IObject* a = CreateObject(0); IObject* b = CreateObject(1); a->Main(); b->Main(); delete a; delete b; } int main() { AddObject(new A); AddObject(new B); Main(); RemoveAllObjects(); }   AddObject add the object description and associate it with an index, CreateObject should create it. It works, but the problem is that with AddObject I'm creating two objects that they will be never used. I'd like to to something like AddObject(A), AddObject(B) without to create them, next create for the first time for example the object B calling CreateObject(1), without to have a startup object where to take informations about how to use the memory. I want it totally dynamic, I won't use a switch(index) { case 0: return new A; etc.  So, it's possible to create something like a Class list instead of an object list?
  3. I read carefully all the replies, thanks for the tips. I learned OpenGL 1.1 and 2.1 some time ago, but I don't now many things of Direct3D9 (for example the possibility to specify the vertex declaration without using FVF), the global shader uniforms (thanks mhagain for this information) and others. Fortunately the framework will be pretty tiny, it will support a single vertex and fragment shader (directly compiled and used during the initialization until the end of the application), specify the view matrix only during window resizing, no world matrix (I'm translating all the vertices from CPU side for specific reasons); the only thing that the framework should do, is to initialize the rendering device, set the view, create and/or load the texture and accept indexed vertices. I think that the "preferred API" can be a choice in application / games that requires a lot of performance with heavy 3D models and effects. So until now, I've a virtual class with these members: GetDeviceName(), Initialize, SetClearColor(float, float, float), RenderBegin (handles glBegin or pd3d9->BeginScene if it's fixed pipelne), RenderEnd (glEnd or pd3d9->EndScene() with the swap of the backbuffer), SendVertices(data, count, primitiveType), CreateTexture(id&, width, height, format), UseTexture(id) and SetView(width, height). All the works from the render device (like shader creation, uniform assignments, stores various textures in a single big texture, vertices caching, texture filtering, render to texture (glcopyteximage2d should works with GL 2.1<) etc) will be transparent, like a black box. The framework works fine with rotated sprites, cubes etc, the only weird thing that I noticed is that Direct3D9 handles the colors as ABGR and OpenGL as ARGB, but I can imagine that shaders will cover this issue.    So with big projects, a preferred API is chosen and during portings these APIs are wrapped, right? This remember me that Final Fantasy 1 for Windows Phone is a porting of Android version that it's also a porting of the iOS, that finally it's a porting of PSP version, in fact the game is... horrible. In cases of powerful engines that promises high performances like Unity, UDK etc, they program it directly with the low-levels things and during the porting they change most of the code without to wrap the original API? 
  4. Yes, I found the vertex declaration more flexible than FVF. How D3D supports individual attributes? And how I can say if the GPU prefeer packed or individual vertices attributes? Seems that OpenGL manages better in a way, Direct3D9 in another way. I found the D3D9 compatibility mode here.    This can be a solution obviously, but can be overweight as works in cases of a lot of vertices. Currently I'm creating a lot of vertices at runtime that handles sprites with XYZ coords, UV coords, colors and a value that points to the palette index (the value is processed by the fragment shader).
  5. Hi, I'm currently working on an abstraction layer between Direct3D9 and OpenGL 2.1. Basically there is a virtual class (the rendering interface) that can be implemented with D3D9 or GL21 class. The problem that I have is that I don't know how to store and send the vertices. D3D9 provides FVF where every vertices contains position, texture uv and color in a DWORD value. OpenGL handles the single vertices' elements in different locations of memory (an array for position, an array for texture uv and an array for color in vec4 float format). Basically I want an independent way to create vertices, the application should store them in a portion of memory, then send them all at once to the render interface, but how? I know that OpenGL can handle the vertices in D3D compatibility mode (with glVertexAttribPointer, managing stride and pointer value) that seems to be slower than the native way, but how to manage for example the colors? D3D9 accepts a single 32-bit value in integer format, OpenGL manages it in a more dynamic (but heavy) way, storing each color's channel in a 32-bit floating point value. In this case I can handle the 32-bit integer value inside the vertex shader and then convert it in a vec4 right? But all these operations seems to be too heavy. In the future I want that this abstraction layer is good enough to implement other rendering engines like Direct3D11, OpenGL ES 2.0 and others. So my main question is: there is a nice way to abstract these two rendering API without to change the rest of the code that uses the rendering interface? 
  6. Okay, in these days I rewrote the entire sprite system. I'm using a pre-calculated unsigned short array for vertex indices and I'm copying the four vertices for each sprite in an array that is used as a cache. Now the framework reaches 997 fps with 20000 triangles. I'm currently using glVertexPointer and glDrawElements due to OpenGL 2.1 compatibility. I'm binding only one texture per frame. I discovered that the rendering isn't really CPU-limited, in fact I overclocked my video-card (it was in under clock to save power) and the framework reaches 1800fps. For VBO I don't understand exactly how to initialize and use it properly, it isn't the same thing to cache all the vertices in main memory then send all together before to call SwapBuffers? I forgot also to mention that more or less the 90% of the vertices changes every frame, so caching them inside the video-card has't a great effect... Also I don't understand how to buffer the uniforms and how to use them. It's possible also to avoid the glBindTexture? I know that I can upload the textures in a single big texture, but I'm asking if there is another way to switch with a batch/buffer the texture binding.
  7.   If you gave us more details about the way you have measured the time, maybe we could find the cause. SwapBuffers is not a time-consuming instruction. The reason it take time is waiting for drawing to finish. That implies your measured time is incorrect. How did you measured it? I'm measuring it with gDEBugger, setting SwapBuffer as end-of-frame. With the profiling of Visual Studio, I can see clearly that SwapBuffers takes the 50% of the CPU in a single frame.
  8. I did some tests: 1) Call glVertexAttribPointer and glDrawArrays with GL_TRIANGLE_STRIP for every sprite (the original mode before to create this post), reaches 498fps. The stride here is 0, this mean that vertex position, texture position and color are in separate structures. 2) Cache the vertices in an array of 1024 structures. I'm copying the vertices that I'm passing to the cache with a memcpy. When the array is full, the content is drawn with glVertexAttribPointer and glDrawElements with GL_TRIANGLE_STRIP. I'm indexing the vertices here. The stride is 0. 589fps!!! 3) Same as above, but vertex position, texture position and color are on the same structure, this mean that I need to call memcpy to copy the sprite model, only once. I was expecting an improvment. 399fps. 4) Same as 4, but this time I'm unpacking the vertices from GL_TRIANGLE_STRIP to GL_TRIANGLES. I'm passing the 4 vertices and a function unpack them to 6 vertices. With this I don't need of indexed vertices. This takes much memory but the fps reached are 562! 5) Same as 3, but this time I'm using VBO: only 270fps. 6) Same as 4 but with VBO: 278fps.   Supposing that I'm not doing nothing's wrong, the best mode is the second. It doesn't take much memory and the indexing mode is easy to do. With this I can hardcode some basic models and indexing them. The vertex unpacking from STRIP to LIST can takes a lot of resources and it doesn't improve so much. I should avoid the structures all-in-one (I read from OpenGL documentation that it's implemented for D3D compatibility) and stores every attrib in a separate structure. For some reason, VBO decrease the performances and with this, SwapBuffer takes a lot of CPU. However all this methods are CPU-limited, because the GPU isn't totally used. Much of the CPU is drawined by memcpy and SwapBuffer.   EDIT: I tried the same tests with the same software without edits on another computer that handle a Intel HD3000 (the first tests run on a Radeon 4870HD): 62, 178, 124, 163, 97, 207fps. VBO with triangle list is much faster this time. I'm starting to be confused...
  9. Okay, I reduced the uses of shaders to one only and I've implemented the uses of VBO. I'm unpacking the triangle strip to a triangle list into a structure with 512 * sizeof(Vertex) size. I'm building and drawing the VBO when the structure is filled with this: glBufferData(GL_ARRAY_BUFFER, m_vertexcacheIndex * sizeof(SuperVertex), m_vertexcache, GL_DYNAMIC_DRAW); glVertexAttribPointer(vert_position, 3, GL_FLOAT, GL_FALSE, sizeof(SuperVertex), BUFFER_OFFSET(0 * sizeof(float))); glVertexAttribPointer(vert_texture, 3, GL_FLOAT, GL_FALSE, sizeof(SuperVertex), BUFFER_OFFSET(3 * sizeof(float))); glVertexAttribPointer(vert_color, 4, GL_FLOAT, GL_FALSE, sizeof(SuperVertex), BUFFER_OFFSET(6 * sizeof(float))); glDrawArrays(GL_TRIANGLES, 0, m_vertexcacheIndex); m_vertexcacheIndex = 0;   where m_vertexcacheIndex is the vertices count inside th structure, m_vertexcache is the structure itself and supervertex is the structure definition. I debugged the software with gDEBugger, before VBO I was doing 12k gl calls per frame, now only 120 calls but I have bad performances. Before 720fps, now 350... 
  10. So if I have 100 sprites I should send 100 view model matrix with glUniformMatrix4fv and select them with gl_VertexID/4?   I'm not sure what you mean by this, but maybe what you want is instancing. Uniform buffers make sharing easy. Yes, I mean instancing (I saw what instancing is it only now). Do you recommend me to send matrices in an uniform array or in a texture? 
  11. OpenGL Default color attribute

      Yes, my laptop with a Intel Atom Z supports only OpenGL 2.1. My real goal is to have a multi-platform framework, with OpenGL 2.1/3.0+/ES1.0/ES2.0 and probably also DirectX 11 for W8 and WP8. OpenGL 3.0 offers great improvements and cool stuff (one of these things that I wanted is "rendering to texture") but I'm not excluding the old platforms :)
  12. Hi, I'm interested on a bit of theory about the best methods of optimization for OpenGL 3.0 (where a lot of function became deprecated). On my current 2D framework, every sprite has own program with own values inside the uniform. Every sprite is draw separately and, now that I switched from 2.1 to 3.0, every sprite has own matrix Projection and View. Now my goal is to batch most vertexes possible and these are some ideas: 1) Use only one program for everything. The projection matrix is one, i can group the vertexes and send via glVertexAttribArray the values for shader and draw everything with one call. The problem is the model view matrix, that should be one for every vertex and this isn't the thing that I want because every sprite has own matrix. 2) Continue to use various shader. The projection matrix is shared between programs (how can I do it?), every sprite has own shader with own model view matrix and uniform values. The problem here is that I need to switch the program between sprite draws.   None of these ideas work as I expected so now I'm here to ask you what is it the most efficient way to batch drawings in OpenGL 3.0.
  13. OpenGL Default color attribute

    Haha that's it? It works fine :D thank you!
  14. Hi, I'm converting my application from using OpenGL 2.0 to OpenGL 3.0. I was using glVertexPointer, glTexCoordPointer and glColorPointer to send the vertices to the GPU and when I doesn't need of Color, I simply disabled it with glDisableClientState(GL_TEXTURE_COORD_ARRAY), so the GPU set gl_Color from vertex shader is white by default.  Now I'm using glDisableVertexAttribArray to disable the vertices and glVertexAttribPointer to send stuff and now comes the problem. glDisableVertexAttribArray(COLOR) set black the color by default in vertex shader! Now I won't fill all the vertices of 1.0f and force to enable the color, so I'm asking you if there is a way to not send the color where it doesn't required without to use particular tricks (like to create a fragment shader for color stuff and another fragment shader to the texture-only stuff).   My shaders looks like this: #version 330 core varying vec3 texcoord; varying vec4 vertex_color; in vec4 in_Position; in vec4 in_Color; in vec4 in_Texture; void main() { gl_Position = in_Position; texcoord = in_Texture; vertex_color = in_Color; } #version 330 core uniform sampler3D texture varying vec3 texcoord; varying vec4 vertex_color; void main() { vec4 precolor = texture3D(texture, texcoord); precolor *= vertex_color; gl_FragColor = precolor; }      
  15. nVidia bug on texture depth?

    (layer+.5f) / textureDepth resolved the problem! It's a good idea to take the Z in the middle of the texture! However I'm using a GeForce 620M. There are no possibilities that textureDepth is 0 due to some checks (textureDepth is a private member in my class)
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