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  • Dot Matrix printers setup...

    - by Parhs
    Hello! I am using debian which is similar to ubuntu. They have 7 dot matrix printers some very old like this one http://www.omnidatasys.net/product/desc_printer_ti880.htm which works from 1979 daily and at text is faster than many inkjects. I believe that it has his own language... Sending text to serial port (port server) prints garbage. However i think is prints only capital english up to 95 asccii and greek and the rest up to 127 i think greek capital.(special chip ) Sending english capital letters prints garbage i think but i amnt sure... i will try again... The other printer are ESC/P compatible and i use generic epson driver provided from ghostscript... However i think that sending text via lp -dpr1 filename It prints the text as a grafic...Changing from printer font face(courier,times roman etc) or pitch has no effect... I am wondering if is there any work arround for this? In AIX they claim that lp command printed output as text as it prints and cobol programs send raw text to to lp printers . However in AIX they use some custom filters for the printers and has more options for dot matrix printers.. I would like to know if there is a solution for this.. To avoid graphics mode for text and change font face somehow.. The most Straight-through approach would be to use no driver ,just send ESC/P from cobol but this requires too much work... Thank you again!

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  • template style matrix implementation in c

    - by monkeyking
    From time to time I use the following code for generating a matrix style datastructure typedef double myType; typedef struct matrix_t{ |Compilation started at Mon Apr 5 02:24:15 myType **matrix; | size_t x; |gcc structreaderGeneral.c -std=gnu99 -lz size_t y; | }matrix; |Compilation finished at Mon Apr 5 02:24:15 | | matrix alloc_matrix(size_t x, size_t y){ | if(0) | fprintf(stderr,"\t-> Alloc matrix with dim (%lu,%lu) byteprline=%lu bytetotal:%l\| u\n",x,y,y*sizeof(myType),x*y*sizeof(myType)); | | myType **m = (myType **)malloc(x*sizeof(myType **)); | for(size_t i=0;i<x;i++) | m[i] =(myType *) malloc(y*sizeof(myType *)); | | matrix ret; | ret.x=x; | ret.y=y; | ret.matrix=m; | return ret; | } And then I would change my typedef accordingly if I needed a different kind of type for the entries in my matrix. Now I need 2 matrices with different types, an easy solution would be to copy/paste the code, but is there some way to do a template styled implementation. Thanks

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  • theoretical and practical matrix multiplication FLOP

    - by mjr
    I wrote traditional matrix multiplication in c++ and tried to measure and compare its theoretical and practical FLOP. As I know inner loop of MM has 2 operation therefore simple MM theoretical Flops is 2*n*n*n (2n^3) but in practice I get something like 4n^3 + number of operation which is 2 i.e. 6n^3 also if I just try to add up only one array a[i][j]++ practical flops then calculate like 3n^3 and not n^3 as you see again it is 2n^3 +1 operation and not 1 operation * n^3 . This is in case if I use 1D array in three nested loops as Matrix multiplication and compare flop, practical flop is the same (near) the theoretical flop and depend exactly as the number of operation in inner loop.I could not find the reason for this behaviour. what is the reason in both case? I know that theoretical flop is not the same as practical one because of some operations like load etc. system specification: Intel core2duo E4500 3700g memory L2 cache 2M x64 fedora 17 sample results: Matrix matrix multiplication 512*512 Real_time: 1.718368 Proc_time: 1.227672 Total flpops: 807,107,072 MFLOPS: 657.429016 Real_time: 3.608078 Proc_time: 3.042272 Total flpops: 807,024,448 MFLOPS: 265.270355 theoretical flop: 2*512*512*512=268,435,456 Practical flops= 6*512^3 =807,107,072 Using 1 dimensional array float d[size][size]:512 or any size for (int j = 0; j < size; ++j) { for (int k = 0; k < size; ++k) { d[k]=d[k]+e[k]+f[k]+g[k]+r; } } Real_time: 0.002288 Proc_time: 0.002260 Total flpops: 1,048,578 MFLOPS: 464.027161 theroretical flop: *4n^2=4*512^2=1,048,576* practical flop : 4n^2+overhead (other operation?)=1,048,578 3 loop version: Real_time: 1.282257 Proc_time: 1.155990 Total flpops: 536,872,000 MFLOPS: 464.426117 theoretical flop:4n^3 = 536,870,912 practical flop: *4n^3=4*512^3+overheads(other operation?)=536,872,000* thank you

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  • C++ BigInt multiplication conceptual problem

    - by Kapo
    I'm building a small BigInt library in C++ for use in my programming language. The structure is like the following: short digits[ 1000 ]; int len; I have a function that converts a string into a bigint by splitting it up into single chars and putting them into digits. The numbers in digits are all reversed, so the number 123 would look like the following: digits[0]=3 digits[1]=3 digits[2]=1 I have already managed to code the adding function, which works perfectly. It works somewhat like this: overflow = 0 for i ++ until length of both numbers exceeded: add numberA[ i ] to numberB[ i ] add overflow to the result set overflow to 0 if the result is bigger than 10: substract 10 from the result overflow = 1 put the result into numberReturn[ i ] (Overflow is in this case what happens when I add 1 to 9: Substract 10 from 10, add 1 to overflow, overflow gets added to the next digit) So think of how two numbers are stored, like those: 0 | 1 | 2 --------- A 2 - - B 0 0 1 The above represents the digits of the bigints 2 (A) and 100 (B). - means uninitialized digits, they aren't accessed. So adding the above number works fine: start at 0, add 2 + 0, go to 1, add 0, go to 2, add 1 But: When I want to do multiplication with the above structure, my program ends up doing the following: Start at 0, multiply 2 with 0 (eek), go to 1, ... So it is obvious that, for multiplication, I have to get an order like this: 0 | 1 | 2 --------- A - - 2 B 0 0 1 Then, everything would be clear: Start at 0, multiply 0 with 0, go to 1, multiply 0 with 0, go to 2, multiply 1 with 2 How can I manage to get digits into the correct form for multiplication? I don't want to do any array moving/flipping - I need performance!

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  • How to prevent 2D camera rotation if it would violate the bounds of the camera?

    - by Andrew Price
    I'm working on a Camera class and I have a rectangle field named Bounds that determines the bounds of the camera. I have it working for zooming and moving the camera so that the camera cannot exit its bounds. However, I'm a bit confused on how to do the same for rotation. Currently I allow rotating of the camera's Z-axis. However, if sufficiently zoomed out, upon rotating the camera, areas of the screen outside the camera's bounds can be shown. I'd like to deny the rotation assuming it meant that the newly rotated camera would expose areas outside the camera's bounds, but I'm not quite sure how. I'm still new to Matrix and Vector math and I'm not quite sure how to model if the newly rotated camera sees outside of its bounds, undo the rotation. Here's an image showing the problem: http://i.stack.imgur.com/NqprC.png The red is out of bounds and as a result, the camera should never be allowed to rotate itself like this. This seems like it would be a problem with all rotated values, but this is not the case when the camera is zoomed in enough. Here are the current member variables for the Camera class: private Vector2 _position = Vector2.Zero; private Vector2 _origin = Vector2.Zero; private Rectangle? _bounds = Rectangle.Empty; private float _rotation = 0.0f; private float _zoom = 1.0f; Is this possible to do? If so, could someone give me some guidance on how to accomplish this? Thanks. EDIT: I forgot to mention I am using a transformation matrix style camera that I input in to SpriteBatch.Begin. I am using the same transformation matrix from this tutorial.

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  • Strange 3D game engine camera with X,Y,Zoom instead of X,Y,Z

    - by Jenko
    I'm using a 3D game engine, that uses a 4x4 matrix to modify the camera projection, in this format: r r r x r r r y r r r z - - - zoom Strangely though, the camera does not respond to the Z translation parameter, and so you're forced to use X, Y, Zoom to move the camera around. Technically this is plausible for isometric-style games such as Age Of Empires III. But this is a 3D engine, and so why would they have designed the camera to ignore Z and respond only to zoom? Am I missing something here? I've tried every method of setting the camera and it really seems to ignore Z. So currently I have to resort to moving the main object in the scene graph instead of moving the camera in relation to the objects. My question: Do you have any idea why the engine would use such a scheme? Is it common? Why? Or does it seem like I'm missing something and the SetProjection(Matrix) function is broken and somehow ignores the Z translation in the matrix? (unlikely, but possible) Anyhow, what are the workarounds? Is moving objects around the only way? Edit: I'm sorry I cannot reveal much about the engine because we're in a binding contract. It's a locally developed engine (Australia) written in managed C# used for data visualizations. Edit: The default mode of the engine is orthographic, although I've switched it into perspective mode. Its probably more effective to use X, Y, Zoom in orthographic mode, but I need to use perspective mode to render everyday objects as well.

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  • 3D rotation matrices deform object while rotating

    - by Kevin
    I'm writing a small 3D renderer (using an orthographic projection right now). I've run into some trouble with my 3D rotation matrices. They seem to squeeze my 3D object (a box primitive) at certain angles. Here's a live demo (only tested in Google Chrome): http://dl.dropbox.com/u/109400107/3D/index.html The box is viewed from the top along the Y axis and is rotating around the X and Z axis. These are my 3 rotation matrices (Only rX and rZ are being used): var rX = new Matrix([ [1, 0, 0], [0, Math.cos(radiants), -Math.sin(radiants)], [0, Math.sin(radiants), Math.cos(radiants)] ]); var rY = new Matrix([ [Math.cos(radiants), 0, Math.sin(radiants)], [0, 1, 0], [-Math.sin(radiants), 0, Math.cos(radiants)] ]); var rZ = new Matrix([ [Math.cos(radiants), -Math.sin(radiants), 0], [Math.sin(radiants), Math.cos(radiants), 0], [0, 0, 1] ]); Before projecting the verticies I multiply them by rZ and rX like so: vert1.multiply(rZ); vert1.multiply(rX); vert2.multiply(rZ); vert2.multiply(rX); vert3.multiply(rZ); vert3.multiply(rX); The projection itself looks like this: bX = (pos.x + (vert1.x*scale)); bY = (pos.y + (vert1.z*scale)); Where "pos.x" and "pos.y" is an offset for centering the box on the screen. I just can't seem to find a solution to this and I'm still relativly new to working with Matricies. You can view the source-code of the demo page if you want to see the whole thing.

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  • PeopleSoft HCM @ OHUG 11: Enter the Matrix

    - by Jay Zuckert
    The PeopleSoft HCM team is back from a very busy and exciting OHUG conference in Orlando. The packed, standing-room only PeopleSoft HCM Roadmap keynote was the highlight of the conference for many attendees and the reviews are in : PeopleSoft rocked the house ! Great demonstration of products in the keynote. Best keynote in a long time, and fun. Engaging and entertaining, great demonstration of capabilities. Message received loud and clear, PeopleSoft applications are here to stay.  PeopleSoft has a real vision moving forward. Real-time polls using mobile texting were cutting edge.                          Tracy Martin (as Trinity) and other members of the PeopleSoft HCM team presented a ‘must-see’ Matrix-themed session while dressed as movie characters. The keynote highlighted planned HCM capabilities for Matrix administration and future organization visualization enhancements. The team also previewed the planned Manager Dashboard and Talent Summary.                           Following the keynote, some of the cast posed for photo opportunities at the OHUG booth in the exhibition hall. As you can imagine, they received some interesting looks walking by the other vendor booths. The PeopleSoft HCM team also presented numerous other OHUG sessions covering PeopleSoft Talent Management, Compensation, HR HelpDesk, Payroll, Global HCM Practices, Time & Labor, Absence Management, and Benefits. All of those presentations are available from the OHUG site at www.ohug.org. When not in one of the well-attended PeopleSoft HCM sessions, conference attendees filled the Oracle booth in the exhibition hall to see live product demonstrations. True to their PeopleSoft roots, some of the PeopleSoft HCM team played as hard as they worked in Orlando and enjoyed the OHUG Appreciation event along with customers at the Hard Rock. We are already busy planning for Oracle OpenWorld 2011 and prepping sessions our PeopleSoft HCM customers are sure to like. We hope to see you there in San Francisco from Oct. 2-6. To learn more about OpenWorld or to register, click here.

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  • Card deck and sparse matrix interview questions

    - by MrDatabase
    I just had a technical phone screen w/ a start-up. Here's the technical questions I was asked ... and my answers. What do think of these answers? Feel free to post better answers :-) Question 1: how would you represent a standard 52 card deck in (basically any language)? How would you shuffle the deck? Answer: use an array containing a "Card" struct or class. Each instance of card has some unique identifier... either it's position in the array or a unique integer member variable in the range [0, 51]. Shuffle the cards by traversing the array once from index zero to index 51. Randomly swap ith card with "another card" (I didn't remember how this shuffle algorithm works exactly). Watch out for using the same probability for each card... that's a gotcha in this algorithm. I mentioned the algorithm is from Programming Pearls. Question 2: how to represent a large sparse matrix? the matrix can be very large... like 1000x1000... but only a relatively small number (~20) of the entries are non-zero. Answer: condense the array into a list of the non-zero entries. for a given entry (i,j) in the array... "map" (i,j) to a single integer k... then use k as a key into a dictionary or hashtable. For the 1000x1000 sparse array map (i,j) to k using something like f(i, j) = i + j * 1001. 1001 is just one plus the maximum of all i and j. I didn't recall exactly how this mapping worked... but the interviewer got the idea (I think). Are these good answers? I'm wondering because after I finished the second question the interviewer said the dreaded "well that's all the questions I have for now." Cheers!

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  • SSRS 2005 Matrix and border styles when exporting to XLS

    - by Mufasa
    The Matrix in SSRS (SQL Server Reporting Services 2005) seems to have issues with certain the border styles when exporting to XLS (but not PDF or web view; maybe other formats, not sure?). For example: Create a matrix and set the Matrix border style to Black Solid 1px, but all 4 of the cells to have a border style of Black None 1px. When viewed via the ASP.NET control, it looks correct. But after export to XLS, it creates borders around all of the header cells (column and row headers, and the top left cell), and even the right most data column. But all the cells in the middle of the report correctly have no border set. Update: If the Matrix borders are set to None, then the borders on the cells don't show up in XLS. So, how do you set an outer border around the Matrix, but not have it apply the 'all sides' border to every cell that touches the edge of the Matrix when exported to Excel?

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  • One row is skipped each time the program scans a matrix from file !

    - by ZaZu
    Hello there, I had this code working yesterday, but it seems like I edited it a bit and lost the working version. I cant get this to work anymore. I basically want to scan a matrix from a .txt file. But each time it scans the first row, the second one is skipped, and it reads the third instead :( Here is my code : for(i=0;i<=test->rowmat1;i++){ for(j=0;j<=test->colmat1;j++){ fscanf(fin,"%f\t",&test->mat[i][j]); } fscanf(fin,"%*[^\n]",&test->mat[i][j]); } For example, for a matrix of : 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 If I extract 3 rows and 3 cols, I get : 1.00 2.00 3.00 7.00 8.00 9.00 Then fails, it wants to skip over the second line but there is nothing after 10 11 12 Why did it stop working ? What do I have wrong ? Please help, Thanks in advance.

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  • Can I make a matrix row group span its child groups in SSRS?

    - by AaronSieb
    I have a matrix, whose rows are grouped into two groups. A class, and a time for that class. The class cell is going to end up being several lines long, and I'd like the rows for each time slot of the class to line up next to the class description, like this: ----------------------------------------- **Class** | 7:00am | [row data] Description of |---------------------- the class, this | 12:00pm | [row data] is several lines |---------------------- long. | 1:00pm | [row data] ----------------------------------------- But what I'm getting is this: ----------------------------------------- **Class** | 7:00am | [row data] Description of | | the class, this | | is several lines | | long. | | ----------------------------------------- | 12:00pm | [row data] | | | | | | | | ----------------------------------------- | 1:00pm | [row data] | | | | | | | | ----------------------------------------- Is there any way to make SSRS collapse the matrix?

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  • Are CMAttitude and CATransform3D related by rotational matrices?

    - by Alex Stone
    I'm looking at the core motion class CMAttitude, it can express the device's orientation as a 3x3 rotational matrix. At the same time I've taken a look at the CATransform3D, which encapsulates the view's attitude, as well as scaling. The CATransform3D is a 4x4 matrix. I've seen that the OpenGL rotational matrix is 4x4 and is simply 0001 padded in the 4th row and column. I'm wandering if the CMAttitude's rotational matrix is related to CATransform's matrix? Can I use the device's rotation in space obtained via a rotational matrix to transform a UIView using CATransform3D? My intention is to let the user move the phone and apply the same transform to a UIView on the screen. Bonus question: if they are related, how do I transform a CMAttitude's rotational matrix to CATransform3D?

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  • How can I find out how many rows of a matrix satisfy a rather complicated criterion (in R)?

    - by Brani
    As an example, here is a way to get a matrix of all possible outcomes of rolling 4 (fair) dice. z <- as.matrix(expand.grid(c(1:6),c(1:6),c(1:6),c(1:6))) As you may already have understood, I'm trying to work out a question that was closed, though, in my opinion, it's a challenging one. I used counting techniques to solve it (I mean by hand) and I finaly arrived to a number of outcomes, with a sum of subset being 5, equal to 1083 out of 1296. That result is consistent with the answers provided to that question, before it was closed. I was wondering how could that subset of outcomes (say z1, where dim(z1) = [1083,4] ) be generated using R. Do you have any ideas? Thank you.

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  • k-means clustering in R on very large, sparse matrix?

    - by movingabout
    Hello, I am trying to do some k-means clustering on a very large matrix. The matrix is approximately 500000 rows x 4000 cols yet very sparse (only a couple of "1" values per row). The whole thing does not fit into memory, so I converted it into a sparse ARFF file. But R obviously can't read the sparse ARFF file format. I also have the data as a plain CSV file. Is there any package available in R for loading such sparse matrices efficiently? I'd then use the regular k-means algorithm from the cluster package to proceed. Many thanks

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  • matrix = *((fxMatrix*)&d3dMatrix); //Evil?

    - by Xilliah
    I've been using matrix = *((fxMatrix*)&d3dMatrix); for quite a while. It worked fine until my screen turned black and received a bucket of frustration on my desk. fxMatrix contains 4 fxVectors. fxVector used to be 16 bytes, but now it was suddenly 20. This was because it inherited fxStreamable, which added the vTable. So one solution is of course just to not inherit fxStreamable, and leave a comment saying that it must always be 16 bytes and never more. Another solution would be to make conversion functions, and copy the matrix completely. This makes it more secure, but has an impact on the performance. I suppose this is the best idea. Another solution is to not convert at all, and stick to D3DXMATRIX, but this makes the engine inconsistent and I personally really dislike this idea. What is your opinion?

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  • Notebook display problem (multiplication)

    - by SubniC
    Hi, I'm having some troubles with the display of a LG E500 notebook. The thing is that without any known reason the display starts to show the screen divided in eigth parts and each part show the display image as if I had a matrix of eigth displays :) I thought it could be some kind of refresh rate problem or driver related, but it is happening at boot-up as well and the BIOS. I got the computer completely unassambled yesterday and I check all the wires and connectors looking for something broken or unconected, but without luck... You can see a picture here of the problem (sorry for the low quality, but I think it illustrate the problem. EDIT 1: I uploaded a new pictrue, here you cans ee the problem better :) There are three horizontal lines that you can see just between the windows. You can see the grey line at the first moment you turn on the computer and the after the duplicated screens show up just like if they where arranged over a grid (over the horizontal lines...) I hope it makes any sense. Do you know what could be happening? or can you tell me what would you do? Thank you very much for your help.

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  • OpenGL's matrix stack vs Hand multiplying

    - by deft_code
    Which is more efficient using OpenGL's transformation stack or applying the transformations by hand. I've often heard that you should minimize the number of state transitions in your graphics pipeline. Pushing and popping translation matrices seem like a big change. However, I wonder if the graphics card might be able to more than make up for pipeline hiccup by using its parallel execution hardware to bulk multiply the vertices. My specific case. I have font rendered to a sprite sheet. The coordinates of each character or a string are calculated and added to a vertex buffer. Now I need to move that string. Would it be better to iterate through the vertex buffer and adjust each of the vertices by hand or temporarily push a new translation matrix?

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  • planar shadow matrix and plane b value

    - by DevExcite
    I implemented planar shadows with the function D3DXMatrixShadow. As you know, we need plane and light factor to calculate a shadow matrix. The problem is that when I set the plane as D3DXPLANE p(0, -1, 0, 0.1f), the shadows by directional light are correctly rendered, but the shadows by point light are not rendered. However, if I use D3DXPLANE p(0, 1, 0, 0.1f), the situation is reversed, shadows by directional light are not drawn, the shadows by point light are ok. I cannot understand why it happens. Is it normal or am i missing something? Please explain to me why this happens. Thanks in advance.

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  • Extract derived 3D scaling from a 3D Sprite to set to a 2D billboard

    - by Bill Kotsias
    I am trying to get the derived position and scaling of a 3D Sprite and set them to a 2D Sprite. I have managed to do the first part like this: var p:Point = sprite3d.local3DToGlobal(new Vector3D(0,0,0)); billboard.x = p.x; billboard.y = p.y; But I can't get the scaling part correctly. I am trying this: var mat:Matrix3D = sprite3d.transform.getRelativeMatrix3D(stage); // get derived matrix(?) var scaleV:Vector3D = mat.decompose()[2]; // get scaling vector from derived matrix var scale:Number = scaleV.length; billboard.scaleX = scale; billboard.scaleY = scale; ...but the result is apparently wrong. PS. One might ask what I am trying to achieve. I am trying to create "billboard" 3D sprites, i.e. sprites which are affected by all 3D transformations except rotations, thus they always face the "camera".

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  • Camera lookAt target changes when rotating parent node

    - by Michael IV
    have the following issue.I have a camera with lookAt method which works fine.I have a parent node to which I parent the camera.If I rotate the parent node while keeping the camera lookAt the target , the camera lookAt changes too.That is nor what I want to achieve.I need it to work like in Adobe AE when you parent camera to a null object:when null object is rotated the camera starts orbiting around the target while still looking at the target.What I do currently is multiplying parent's model matrix with camera model matrix which is calculated from lookAt() method.I am sure I need to decompose (or recompose ) one of the matrices before multiplying them .Parent model or camera model ? Anyone here can show the right way doing it ? UPDATE: The parent is just a node .The child is the camera.The parented camera in AfterEffects works like this: If you rotate the parent node while camera looks at the target , the camera actually starts orbiting around the target based on the parent rotation.In my case the parent rotation changes also Camera's lookAt direction which IS NOT what I want.Hope now it is clear .

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  • Camera closes in on the fixed point

    - by V1ncam
    I've been trying to create a camera that is controlled by the mouse and rotates around a fixed point (read: (0,0,0)), both vertical and horizontal. This is what I've come up with: camera.Eye = Vector3.Transform(camera.Eye, Matrix.CreateRotationY(camRotYFloat)); Vector3 customAxis = new Vector3(-camera.Eye.Z, 0, camera.Eye.X); camera.Eye = Vector3.Transform(camera.Eye, Matrix.CreateFromAxisAngle(customAxis, camRotXFloat * 0.0001f)); This works quit well, except from the fact that when I 'use' the second transformation (go up and down with the mouse) the camera not only goes up and down, it also closes in on the point. It zooms in. How do I prevent this? Thanks in advance.

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  • How to transform mesh components?

    - by Lea Hayes
    I am attempting to transform the components of a mesh directly using a 4x4 matrix. This is working for the vertex positions, but it is not working for the normals (and probably not the tangents either). Here is what I have: // Transform vertex positions - Works like a charm! vertices = mesh.vertices; for (int i = 0; i < vertices.Length; ++i) vertices[i] = transform.MultiplyPoint(vertices[i]); // Does not work, lighting is messed up on mesh normals = mesh.normals; for (int i = 0; i < normals.Length; ++i) normals[i] = transform.MultiplyVector(normals[i]); Note: The input matrix converts from local to world space and is needed to combine multiple meshes together.

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