Search Results

Search found 2221 results on 89 pages for 'inverse matrix'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 29/89 | < Previous Page | 25 26 27 28 29 30 31 32 33 34 35 36  | Next Page >

  • android spinning image

    - by user270811
    hi, i am trying to create two spinning wheels, as in pulleys, so everytime the attached rope moves, the two pulleys will rotate. i have tried two approaches: 1) use Matrix.postRotate within the onDraw() method of the View class, which calls the following: private void drawSpinningWheel(Canvas canvas) { try { canvas.save(); Bitmap bitmapOrg = null; int iDrawable = R.drawable.spinning_button; bitmapOrg = BitmapFactory.decodeResource(getResources(), iDrawable); if(bitmapOrg != null) { int width = bitmapOrg.getWidth(); int height = bitmapOrg.getHeight(); int newWidth = 24; int newHeight = 24; // calculate the scale - in this case = 0.4f float scaleWidth = ((float) newWidth) / width; float scaleHeight = ((float) newHeight) / height; // createa matrix for the manipulation Matrix matrix = new Matrix(); // resize the bit map matrix.postScale(scaleWidth, scaleHeight); matrix.postRotate((float) mDegrees++); Bitmap resizedBitmap = Bitmap.createBitmap(bitmapOrg, 0, 0, width, height, matrix, true); canvas.drawBitmap(resizedBitmap, matrix, null); } canvas.restore(); } catch(Exception e) { Log.e(TAG + "drawSpinningWheel", e.getMessage()); } } but it seems like the image not only spins but rotates around another axis 2) use SurfaceView and a separate thread, in the run() call this: private void doDraw(Canvas canvas) { // Draw the background image. Operations on the Canvas accumulate // so this is like clearing the screen. canvas.drawBitmap(mBackgroundImage, 0, 0, null); int yTop = mCanvasHeight - ((int) mY + mSpinningWheelImageHeight / 2); int xLeft = (int) mX - mSpinningWheelImageWidth / 2; ... // Draw the ship with its current rotation canvas.save(); canvas.rotate((float) mHeading++, (float) mX, mCanvasHeight - (float) mY); mSpinningWheelImage.setBounds(xLeft, yTop, xLeft + mSpinningWheelImageWidth, yTop + mSpinningWheelImageHeight); mSpinningWheelImage.draw(canvas); canvas.restore(); } i get the spinning to work but i can't add another spinning wheel. i even tried to create another thread for the second spinning wheel, only one shows up. can someone point me in the right direction? thanks.

    Read the article

  • Faster projected-norm (quadratic-form, metric-matrix...) style computations

    - by thekindamzkyoulike
    I need to perform lots of evaluations of the form X(:,i)' * A * X(:,i) i = 1...n where X(:,i) is a vector and A is a symmetric matrix. Ostensibly, I can either do this in a loop for i=1:n z(i) = X(:,i)' * A * X(:,i) end which is slow, or vectorise it as z = diag(X' * A * X) which wastes RAM unacceptably when X has a lot of columns. Currently I am compromising on Y = A * X for i=1:n z(i) = Y(:,i)' * X(:,i) end which is a little faster/lighter but still seems unsatisfactory. I was hoping there might be some matlab/scilab idiom or trick to achieve this result more efficiently?

    Read the article

  • C++ Template Classes Circular Dependency Problem

    - by TomWij
    We have two classes: template<typename T, typename Size, typename Stack, typename Sparse> class Matrix and template<typename T, typename Size> class Iterator Matrix should be able to return begin and end iterators and Iterator will keep a referrence to the Matrix to access the elements via it's interface. We don't want Iterator to depend on the internal storage of the Matrix to prevent coupling. How can we solve this cyclic dependency problem? (The internal Storage class has the same template parameters as the Matrix class and the same access procedures as the Matrix itself)

    Read the article

  • How can I make XOR work for logical matrix in MATLAB?

    - by Runner
    >> XOR(X,X) ??? Undefined function or method 'XOR' for input arguments of type 'logical'. Why XOR can't be used for logical matrix? And I tried a more simple example: >> A=[1 0;1 0]; >> B=[1 1;0 0]; >> XOR(A,B) ??? Undefined function or method 'XOR' for input arguments of type 'double'. How can I properly use XOR?

    Read the article

  • RDLC item width is dynamic and causing extra pages to be generated (image included)?

    - by Paul Mendoza
    I'm trying to format an RDLC report file in Visual Studio 2008 and I am having a formatting issue. I have a list at the bottom that contains a matrix that expands horizontally to the right. That pink box is just to visualize the problem I'm having. When the report is rendered the matrix expands and instead of filling the pink box with the matrix is pushes the space in the pink box to the right resulting in an extra page when printing the reports. One solution would be to shrink the pink box to be the size of the matrix which I've done. But then when the matrix grows the fields at the top of the report get pushed to the right by the same amount as the growth of the matrix. Can someone please let me know what they think the solution would be? Thank you!

    Read the article

  • how to pass arguments into function within a function in r

    - by jon
    I am writing function that involve other function from base R with alot of arguments. For example (real function is much longer): myfunction <- function (dataframe, Colv = NA) { matrix <- as.matrix (dataframe) out <- heatmap(matrix, Colv = Colv) return(out) } data(mtcars) myfunction (mtcars, Colv = NA) The heatmap has many arguments that can be passed to: heatmap(x, Rowv=NULL, Colv=if(symm)"Rowv" else NULL, distfun = dist, hclustfun = hclust, reorderfun = function(d,w) reorder(d,w), add.expr, symm = FALSE, revC = identical(Colv, "Rowv"), scale=c("row", "column", "none"), na.rm = TRUE, margins = c(5, 5), ColSideColors, RowSideColors, cexRow = 0.2 + 1/log10(nr), cexCol = 0.2 + 1/log10(nc), labRow = NULL, labCol = NULL, main = NULL, xlab = NULL, ylab = NULL, keep.dendro = FALSE, verbose = getOption("verbose"), ...) I want to use these arguments without listing them inside myfun. myfunction (mtcars, Colv = NA, col = topo.colors(16)) Error in myfunction(mtcars, Colv = NA, col = topo.colors(16)) : unused argument(s) (col = topo.colors(16)) I tried the following but do not work: myfunction <- function (dataframe, Colv = NA) { matrix <- as.matrix (dataframe) out <- heatmap(matrix, Colv = Colv, ....) return(out) } data(mtcars) myfunction (mtcars, Colv = NA, col = topo.colors(16))

    Read the article

  • C++ boost ublas + units dimension constraints

    - by aaa
    hello. I am seeking advice on design/general idea on how to force matrix dimension constraints on ublas matrix/vector possibly using boost units. For example, let matrix A have dimensions of time x force (for example) // does not have dimensions, time x force and force x time are not distinguished. matrix<double> A; //something like? dimension<time, force, matrix<double> > A; dimension<force, time, matrix<double> > B = trans(A); have you done something like this or do you have some good idea about how to organize such constraints? Thank you

    Read the article

  • How to read and save data from text file with variable number of columns in a Matrix in Matlab

    - by khan
    I have a text file with integer values. each row contains information about specific object. But unfortunately each row has different number of column. because of which when i try to use file_content = load('txtfile.txt'); it gives me error message that previous number of columns does not match. i also tried to use fgetl, fscanf, etc function but was unsuccessful. Can anybody give me a piece of code, or help me how to read a txt file and save in matrix in matlab. Three sample rows are given below. 1 1 1 1 1 95 17 54 111 92 17 54 111 92 17 54 111 92 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 54 109 92 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 58 109 96 15 58 109 96 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 58 109 96 15 56 109 94 15 56 109 94 15 58 109 96 15 58 109 96 15 56 109 94 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 17 58 111 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 56 109 94 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 1 1 1 2 96 185 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 15 56 109 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 54 107 92 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 13 56 107 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 54 109 92 15 54 109 92 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 1 1 1 3 186 245 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 56 109 94 15 58 109 96 15 58 109 96 15 58 109 96 15 58 109 96 13 58 107 96 13 56 107 94 13 56 107 94 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 56 107 94 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 58 107 96 13 60 107 98 13 58 107 96 13 58 107 96 15 58 109 96 13 58 107 96 As you can see the rows doesn't have equal number of columns. So how can i read and save it in a Matrix. Any help in this regards will be highly appreciated. Thanks

    Read the article

  • R matrix handling expressions aren't evaluated in a function or a "for" loop - Column extract doesn't seem to work

    - by Sal Leggio
    I have an R matrix named ddd. When I enter this, everything works fine: i <- 1 shapiro.test(ddd[,y]) ad.test(ddd[,y]) stem(ddd[,y]) print(y) The calls to Shapiro Wilk, Anderson Darling, and stem all work, and extract the same column. If I put this code in a "for" loop, the calls to Shapiro Wilk, and Anderson Darling stop working, while the the stem & leaf call and the print call continue to work. for (y in 7:10) { shapiro.test(ddd[,y]) ad.test(ddd[,y]) stem(ddd[,y]) print(y) } The decimal point is 1 digit(s) to the right of the | 0 | 0 0 | 899999 1 | 0 [1] 7 The same thing happens if I try and write a function. SW & AD do not work. The other calls do. D <- function (y) { + shapiro.test(ddd[,y]) + ad.test(ddd[,y]) + stem(ddd[,y]) + print(y) } D(9) The decimal point is at the | 9 | 000 9 | 10 | 00000 [1] 9 Why don't all the calls behave the same way?

    Read the article

  • Scala : reference is ambiguous (imported twice)

    - by tk
    I want to use a method as a parameter of another method of the same class. I have a class and objects which are companions: class mM(var elem:Matrix){ //apply a function on a dimension rows (1) or cols (2) def app(func:Iterable[Double]=>Double)(dim : Int) : Matrix = { ... } //utility function def logsumexp(): Double = {...} } object mM{ def apply(elem:Matrix):mM={new mM(elem)} def logsumexp(elem:Iterable[Double]): Double ={ this.apply(elem.asInstanceOf[Matrix]).logsumexp() } } Normally I use logsumexp like this mM(matrix).logsumexp but if want to apply it to the rows I can't use mM(matrix).app(mM.logsumexp)(1), I get the error: error: reference to mM is ambiguous; it is imported twice in the same scope by import mM and import mM What is the most elegant solution ? Should I change logsumexp() to another class ? Thanks,=)

    Read the article

  • Confusion over C++ new operator and classes

    - by Nils
    Hi all I created a simple class in C++ which has a private dynamic array. In the constructor I initialize the array using new and in the destructor I free it using delete. When I instantiate the class using Class a = Class(..); it works as expected, however it seems I cannot instantiate it using the new operator (Like Class *a = new Class(..);), I always get a segmentation fault. What I don't understand is when I should use new to instantiate a class and when just call the constructor or should it be possible to instantiate a class either with new or by just calling the constructor. float** A = new float*[3]; for (int i=0; i<3; i++) { A[i] = new float[3]; } A[0][0] = 3; A[0][1] = 3; A[0][2] = 4; A[1][0] = 5; A[1][1] = 6; A[1][2] = 7; A[2][0] = 1; A[2][1] = 2; A[2][2] = 3; Matrix *M = new Matrix(A, 3, 3); delete[] A; delete M; Below the class definition.. class Matrix { private: int width; int height; int stride; float* elements; public: Matrix(float** a, int n, int m); ~Matrix(); }; Matrix::Matrix(float** a, int n, int m) { // n: num rows // m: elem per rows elements = new float[n*m]; for (int i=0; i<n; i++) { for (int j=0; j<m; j++) { elements[i*n + j] = a[n][m]; } } } Matrix::~Matrix() { delete[] elements; }

    Read the article

  • How do I transform a single colmn list to item matrix in R?

    - by Indy
    I currently have data that is in the following format (note, this is 1 column, 4 row matrix): aa|bb bb|cc|ee|ee cc cc|ee and I want it displayed so that the column names are: aa, bb, cc, dd, and ee. And I want there to be 4 row such that each row counts the number of times each string was present in the matching row above. ie) aa bb cc dd ee 1 1 0 0 0 0 1 1 0 2 0 0 1 0 0 0 0 1 0 1 Does anyone know how to do this in R? I would post my attempt, but it is just getting ugly and complicated. Any help would be much appreciated. Thanks in advance.

    Read the article

  • Is there bug in the Matrix.RotateAt method for certain angles? .Net Winforms

    - by Jules
    Here's the code i'm using to rotate: Dim m As New System.Drawing.Drawing2D.Matrix Dim size = image.Size m.RotateAt(degreeAngle, New PointF(CSng(size.Width / 2), CSng(size.Height / 2))) Dim temp As New Bitmap(600, 600, Imaging.PixelFormat.Format32bppPArgb) Dim g As Graphics = Graphics.FromImage(temp) g.Transform = m g.DrawImage(image, 0, 0) (1) Disposals removed for brevity. (2) I test the code with a 200 x 200 rectangle. (3) Size 600,600 it just an arbitrary large value that I know will fit the right and bottom sides of the rotated image for testing purposes. (4) I know, with this code, the top and left edges will be clipped because I'm not transforming the orgin after the rotate. The problem only occurs at certain angles: (1) At 90, the right hand edge disappears completely. (2) At 180, the right and bottom edges are there, but very faded. (3) At 270, the bottom edge disappears completely. Is this a known bug? If I manually rotate the corners an draw the image by specifying an output rectangle, I don't get the same problem - though it is slightly slower than using RotateAt.

    Read the article

  • DirectX Unproject troubles

    - by pivotnig
    I have an orthographic projection and I try to unproject a point from screen space. Following are the view and projection matrices: var w2 = ScreenWidthInPixels/2; var h2 = ScreenHeightInPixels/2; view = Matrix.LookAtLH(new Vector3(0, 0, -1), new Vector3(0, 0, 0), Vector3.UnitY); proj = Matrix.OrthoOffCenterLH(-w2, w2, -h2, h2, 0.1f, 10f); Here is how I unproject a Point p, the point is given in screen pixels: var m = Vector3.Unproject(p, 0, 0, ScreenWidthInPixels, ScreenHeightInPixels, 0.1f, 10f, // znear and zfar view *proj); My code doesn't work, the matrix m contains only Nan. When I try to invert view * proj I get back a Matrix with only zeros. So I suspect my problem has something to do with the orthographic projection matrix. Here are my questions: Could the problem be caused by an underflow due to the large values in the OrthoOffCenterLH projection? What parameters do I have to pass for x,y,width,height in Unproject(...)? What significance has the minZ and maxZ parameter in Unproject(...)? Does it matter what I pass for p.Z in Unproject(...)?

    Read the article

  • Android OpenGL ES 2 framebuffer not working properly

    - by user16547
    I'm trying to understand how framebuffers work. In order to achieve that, I want to draw a very basic triangle to a framebuffer texture and then draw the resulting texture to a quad on the default framebuffer. However, I only get a fraction of the triangle like below. LE: The triangle's coordinates should be (1) -0.5f, -0.5f, 0 (2) 0.5f, -0.5f, 0 (3) 0, 0.5f, 0 Here's the code to render: @Override public void onDrawFrame(GL10 gl) { renderNormalStuff(); renderFramebufferTexture(); } protected void renderNormalStuff() { GLES20.glViewport(0, 0, texWidth, texHeight); GLUtils.updateProjectionMatrix(mProjectionMatrix, texWidth, texHeight); GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, fbo[0]); GLES20.glUseProgram(mProgram); GLES20.glClearColor(.5f, .5f, .5f, 1); GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT); Matrix.setIdentityM(mModelMatrix, 0); Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0); Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mMVPMatrix, 0); GLES20.glUniformMatrix4fv(u_MVPMatrix, 1, false, mMVPMatrix, 0); GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vbo[0]); GLES20.glVertexAttribPointer(a_Position, 3, GLES20.GL_FLOAT, false, 12, 0); GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vbo[1]); GLES20.glVertexAttribPointer(a_Color, 4, GLES20.GL_FLOAT, false, 16, 0); GLES20.glBindBuffer(GLES20.GL_ELEMENT_ARRAY_BUFFER, ibo[0]); GLES20.glDrawElements(GLES20.GL_TRIANGLES, indexBuffer.capacity(), GLES20.GL_UNSIGNED_BYTE, 0); GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0); GLES20.glBindBuffer(GLES20.GL_ELEMENT_ARRAY_BUFFER, 0); GLES20.glUseProgram(0); } private void renderFramebufferTexture() { GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0); GLES20.glUseProgram(fboProgram); GLES20.glClearColor(.0f, .5f, .25f, 1); GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT); GLES20.glViewport(0, 0, width, height); GLUtils.updateProjectionMatrix(mProjectionMatrix, width, height); Matrix.setIdentityM(mModelMatrix, 0); Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0); Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mMVPMatrix, 0); GLES20.glUniformMatrix4fv(fbo_u_MVPMatrix, 1, false, mMVPMatrix, 0); //draw the texture GLES20.glActiveTexture(GLES20.GL_TEXTURE0); GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture[0]); GLES20.glUniform1i(fbo_u_Texture, 0); GLUtils.sendBufferData(fbo_a_Position, 3, quadPositionBuffer); GLUtils.sendBufferData(fbo_a_TexCoordinate, 2, quadTexCoordinate); GLES20.glDrawElements(GLES20.GL_TRIANGLES, quadIndexBuffer.capacity(), GLES20.GL_UNSIGNED_BYTE, quadIndexBuffer); GLES20.glUseProgram(0); }

    Read the article

  • Reverse horizontal and vertical for a HTML table

    - by porton
    There is a two-dimensional array describing a HTML table. Each element of the array consists of: the cell content rowspan colspan Every row of this two dimensional array corresponds to <td> cells of a <tr> of the table which my software should generate. I need to "reverse" the array (interchange vertical and horizontal direction). Insofar I considered algorithm based on this idea: make a rectangular matrix of the size of the table and store in every element of this matrix the corresponding index of the element of the above mentioned array. (Note that two elements of the matrix may be identical due rowspan/colspan.) Then I could use this matrix to calculate rowspan/colspan for the inverted table. But this idea seems bad for me. Any other algorithms? Note that I program in PHP.

    Read the article

  • Create dynamic buffer SharpDX

    - by fedab
    I want to set a buffer that is updated every frame but can't figure it out, what i have to do. The only working thing i have is this: mdexcription = new BufferDescription(Matrix.SizeInBytes * Matrices.Length, ResourceUsage.Dynamic, BindFlags.VertexBuffer, CpuAccessFlags.Write, ResourceOptionFlags.None, 0); instanceBuffer = SharpDX.Direct3D11.Buffer.Create(Device, Matrices, mdexcription); vBB = new VertexBufferBinding(instanceBuffer, Matrix.SizeInBytes, 0); DeviceContext.InputAssembler.SetVertexBuffers(1, vBB); Draw: //Change Matrices (Matrix[]) every frame... instanceBuffer.Dispose(); instanceBuffer = SharpDX.Direct3D11.Buffer.Create(Device, Matrices, mdexcription); vBB = new VertexBufferBinding(instanceBuffer, Matrix.SizeInBytes, 0); DeviceContext.InputAssembler.SetVertexBuffers(1, vBB); I guess Dispose() and creating a new buffer is slow and can be done much faster. I've read about DataStream but i do not know, how to set this up properly. What steps do i have to do to set up a DataStream to achieve fast every-frame update?

    Read the article

  • Transform between two 3d cartesian coordinate systems

    - by Pris
    I'd like to know how to get the rotation matrix for the transformation from one cartesian coordinate system (X,Y,Z) to another one (X',Y',Z'). Both systems are defined with three orthogonal vectors as one would expect. No scaling or translation occurs. I'm using OpenSceneGraph and it offers a Matrix convenience class, if it makes finding the matrix easier: http://www.openscenegraph.org/documentation/OpenSceneGraphReferenceDocs/a00403.html.

    Read the article

  • Orthographic Projection Issue

    - by Nick
    I have a problem with my Ortho Matrix. The engine uses the perspective projection fine but for some reason the Ortho matrix is messed up. (See screenshots below). Can anyone understand what is happening here? At the min I am taking the Projection matrix * Transform (Translate, rotate, scale) and passing to the Vertex shader to multiply the Vertices by it. VIDEO Shows the same scene, rotating on the Y axis. http://youtu.be/2feiZAIM9Y0 void Matrix4f::InitOrthoProjTransform(float left, float right, float top, float bottom, float zNear, float zFar) { m[0][0] = 2 / (right - left); m[0][1] = 0; m[0][2] = 0; m[0][3] = 0; m[1][0] = 0; m[1][1] = 2 / (top - bottom); m[1][2] = 0; m[1][3] = 0; m[2][0] = 0; m[2][1] = 0; m[2][2] = -1 / (zFar - zNear); m[2][3] = 0; m[3][0] = -(right + left) / (right - left); m[3][1] = -(top + bottom) / (top - bottom); m[3][2] = -zNear / (zFar - zNear); m[3][3] = 1; } This is what happens with Ortho Matrix: This is the Perspective Matrix:

    Read the article

  • Shadows shimmer when camera moves

    - by Chad Layton
    I've implemented shadow maps in my simple block engine as an exercise. I'm using one directional light and using the view volume to create the shadow matrices. I'm experiencing some problems with the shadows shimmering when the camera moves and I'd like to know if it's an issue with my implementation or just an issue with basic/naive shadow mapping itself. Here's a video: http://www.youtube.com/watch?v=vyprATt5BBg&feature=youtu.be Here's the code I use to create the shadow matrices. The commented out code is my original attempt to perfectly fit the view frustum. You can also see my attempt to try clamping movement to texels in the shadow map which didn't seem to make any difference. Then I tried using a bounding sphere instead, also to no apparent effect. public void CreateViewProjectionTransformsToFit(Camera camera, out Matrix viewTransform, out Matrix projectionTransform, out Vector3 position) { BoundingSphere cameraViewFrustumBoundingSphere = BoundingSphere.CreateFromFrustum(camera.ViewFrustum); float lightNearPlaneDistance = 1.0f; Vector3 lookAt = cameraViewFrustumBoundingSphere.Center; float distanceFromLookAt = cameraViewFrustumBoundingSphere.Radius + lightNearPlaneDistance; Vector3 directionFromLookAt = -Direction * distanceFromLookAt; position = lookAt + directionFromLookAt; viewTransform = Matrix.CreateLookAt(position, lookAt, Vector3.Up); float lightFarPlaneDistance = distanceFromLookAt + cameraViewFrustumBoundingSphere.Radius; float diameter = cameraViewFrustumBoundingSphere.Radius * 2.0f; Matrix.CreateOrthographic(diameter, diameter, lightNearPlaneDistance, lightFarPlaneDistance, out projectionTransform); //Vector3 cameraViewFrustumCentroid = camera.ViewFrustum.GetCentroid(); //position = cameraViewFrustumCentroid - (Direction * (camera.FarPlaneDistance - camera.NearPlaneDistance)); //viewTransform = Matrix.CreateLookAt(position, cameraViewFrustumCentroid, Up); //Vector3[] cameraViewFrustumCornersWS = camera.ViewFrustum.GetCorners(); //Vector3[] cameraViewFrustumCornersLS = new Vector3[8]; //Vector3.Transform(cameraViewFrustumCornersWS, ref viewTransform, cameraViewFrustumCornersLS); //Vector3 min = cameraViewFrustumCornersLS[0]; //Vector3 max = cameraViewFrustumCornersLS[0]; //for (int i = 1; i < 8; i++) //{ // min = Vector3.Min(min, cameraViewFrustumCornersLS[i]); // max = Vector3.Max(max, cameraViewFrustumCornersLS[i]); //} //// Clamp to nearest texel //float texelSize = 1.0f / Renderer.ShadowMapSize; //min.X -= min.X % texelSize; //min.Y -= min.Y % texelSize; //min.Z -= min.Z % texelSize; //max.X -= max.X % texelSize; //max.Y -= max.Y % texelSize; //max.Z -= max.Z % texelSize; //// We just use an orthographic projection matrix. The sun is so far away that it's rays are essentially parallel. //Matrix.CreateOrthographicOffCenter(min.X, max.X, min.Y, max.Y, -max.Z, -min.Z, out projectionTransform); } And here's the relevant part of the shader: if (CastShadows) { float4 positionLightCS = mul(float4(position, 1.0f), LightViewProj); float2 texCoord = clipSpaceToScreen(positionLightCS) + 0.5f / ShadowMapSize; float shadowMapDepth = tex2D(ShadowMapSampler, texCoord).r; float distanceToLight = length(LightPosition - position); float bias = 0.2f; if (shadowMapDepth < (distanceToLight - bias)) { return float4(0.0f, 0.0f, 0.0f, 0.0f); } } The shimmer is slightly better if I drastically reduce the view volume but I think that's mostly just because the texels become smaller and it's harder to notice them flickering back and forth. I'd appreciate any insight, I'd very much like to understand what's going on before I try other techniques.

    Read the article

  • Updating physics for animated models

    - by Mathias Hölzl
    For a new game we have do set up a scene with a minimum of 30 bone animated models.(shooter) The problem is that the update process for the animated models takes too long. Thats what I do: Each character has ~30 bones and for every update tick the animation gets calculated and every bone fires a event with the new matrix. The physics receives the event with the new matrix and updates the collision shape for that bone. The time that it takes to build the animation isn't that bad (0.2ms for 30 Bones - 6ms for 30 models). But the main problem is that the physic engine (Bullet) uses a diffrent matrix for transformation and so its necessary to convert it. Code for matrix conversion: (~0.005ms) btTransform CLEAR_PHYSICS_API Mat_to_btTransform( Mat mat ) { btMatrix3x3 bulletRotation; btVector3 bulletPosition; XMFLOAT4X4 matData = mat.GetStorage(); // copy rotation matrix for ( int row=0; row<3; ++row ) for ( int column=0; column<3; ++column ) bulletRotation[row][column] = matData.m[column][row]; for ( int column=0; column<3; ++column ) bulletPosition[column] = matData.m[3][column]; return btTransform( bulletRotation, bulletPosition ); } The function for updating the transform(Physic): void CLEAR_PHYSICS_API BulletPhysics::VKinematicMove(Mat mat, ActorId aid) { if ( btRigidBody * const body = FindActorBody( aid ) ) { btTransform tmp = Mat_to_btTransform( mat ); body->setWorldTransform( tmp ); } } The real problem is the function FindActorBody(id): ActorIDToBulletActorMap::const_iterator found = m_actorBodies.find( id ); if ( found != m_actorBodies.end() ) return found->second; All physic actors are stored in m_actorBodies and thats why the updating process takes to long. But I have no idea how I could avoid this. Friendly greedings, Mathias

    Read the article

  • Vertex fog producing black artifacts

    - by Nick
    I originally posted this question on the XNA forums but got no replies, so maybe someone here can help: I am rendering a textured model using the XNA BasicEffect. When I enable fog, the model outline is still visible as many small black dots when it should be "in the fog". Why is this happening? Here's what it looks like for me -- http://tinypic.com/r/fnh440/6 Here is a minimal example showing my problem: (the ship model that this example uses is from the chase camera sample on this site -- http://xbox.create.msdn.com/en-US/education/catalog/sample/chasecamera -- in case anyone wants to try it out ;)) public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; Model model; public Game1() { graphics = new GraphicsDeviceManager(this); Content.RootDirectory = "Content"; } protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); // TODO: use this.Content to load your game content here model = Content.Load<Model>("ship"); foreach (ModelMesh mesh in model.Meshes) { foreach (BasicEffect be in mesh.Effects) { be.EnableDefaultLighting(); be.FogEnabled = true; be.FogColor = Color.CornflowerBlue.ToVector3(); be.FogStart = 10; be.FogEnd = 30; } } } protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); // TODO: Add your drawing code here model.Draw(Matrix.Identity * Matrix.CreateScale(0.01f) * Matrix.CreateRotationY(3 * MathHelper.PiOver4), Matrix.CreateLookAt(new Vector3(0, 0, 30), Vector3.Zero, Vector3.Up), Matrix.CreatePerspectiveFieldOfView(MathHelper.PiOver4, 16f/9f, 1, 100)); base.Draw(gameTime); } }

    Read the article

  • how to make HLSL effect just for lighning without texture mapping?

    - by naprox
    I'm new to XNA, i created an effect and just want to use lightning but in default effect that XNA create we should do texture mapping or the model appears 'RED', because of this lines of code in the effect file: float4 PixelShaderFunction(VertexShaderOutput input) : COLOR0 { float4 output = float4(1,0,0,1); return output; } and if i want to see my model (appear like when i use basiceffect) must do texture mapping by UV coordinates. but my model does not have UV coordinates assigned or its UV coordinates is not exported. and if i do texture mapping i got error. (i do texture mapping by this line of code in vertexshaderfunction and other necessary codes) output.UV= input.UV i have many of this models and want to work with them.(my models are in .FBX format) when i use Bassiceffect i have no problem and model appears correctly. how can i use "just" lightnings in my custom effects? and don't do texture mapping (because i have no UV coordinates in my models) and my model be look like when i use BasicEffect? if you need my complete code Here it is: http://www.mediafire.com/?4jexhd4ulm2icm2 here is inside of my Model Using BasicEffect http://i.imgur.com/ygP2h.jpg?1 and this is my code for drawing with or without BasicEffect inside of my draw() method: Matrix baseWorld = Matrix.CreateScale(Scale) * Matrix.CreateFromYawPitchRoll(Rotation.Y, Rotation.X, Rotation.Z) * Matrix.CreateTranslation(Position); foreach(ModelMesh mesh in Model.Meshes) { Matrix localWorld = ModelTransforms[mesh.ParentBone.Index] * baseWorld; foreach(ModelMeshPart part in mesh.MeshParts) { Effect effect = part.Effect; if (effect is BasicEffect) { ((BasicEffect)effect).World = localWorld; ((BasicEffect)effect).View = View; ((BasicEffect)effect).Projection = Projection; ((BasicEffect)effect).EnableDefaultLighting(); } else { setEffectParameter(effect, "World", localWorld); setEffectParameter(effect, "View", View); setEffectParameter(effect, "Projection", Projection); setEffectParameter(effect, "CameraPosition", CameraPosition); } } mesh.Draw(); } setEffectParameter is another method that sets effect parameter if i use my custom effect.

    Read the article

  • box2d resize bodies arround point

    - by philipp
    I have a compound object, consisting of a b2Body, vector-graphics and a list polygons which describe the b2body's shapes. This object has its own transformation matrix to centralize the storage of transformations. So far everything is working quiet fine, even scaling works, but not if i scale around a point. In the initialization phase of the object it is scaled around a point. This happens in this order: transform the main matrix transform the vector graphics and the polygons recreate the b2Body After this function ran, the shapes and all the graphics are exactly where they should be, BUT: after the first steps of the b2World the graphical stuff moves away from the body. When I ran the debugger I found out that the position of the body is 0/0 the red dot shows the center of scaling. the first image shows the basic setup and the second the final position of the graphics. This distance stays constant for the rest of the simulation. If I set the position via myBody.SetPosition( sx, sy ); the whole scenario just plays a bit more distant for the origin. Any Idea how to fix this? EDIT:: I came deeper down to the problem and it lies in the fact that i must not scale the transform matrix for the b2body shapes around the center, but set the b2body's position back to the point after scaling. But how can I calculate that point? EDIT 2 :: I came ever deeper down to it, even solved it, but this is a slow solution and i hope that there is somebody who understands what formula I need. assuming to have a set polygons relative to an origin as basis shapes for a b2body: scaling the whole object around a certain point is done in the following steps: i scale everything around the center except the polygons i create a clone of the polygons matrix i scale this clone around the point i calculate dx, dy as difference of clone.tx - original.tx and clone.ty - original.ty i scale the original polygon matrix NOT around the point i recreate the body i create the fixture i set the position of the body to dx and dy done! So what i an interested in is a formula for dx and dy without cloning matrices, scaling the clone around a point, getting dx and dy and finally scale the vertex matrix.

    Read the article

  • Xna GS 4 Animation Sample bone transforms not copying correctly

    - by annonymously
    I have a person model that is animated and a suitcase model that is not. The person can pick up the suitcase and it should move to the location of the hand bone of the person model. Unfortunately the suitcase doesn't follow the animation correctly. it moves with the hand's animation but its position is under the ground and way too far to the right. I haven't scaled any of the models myself. Thank you. The source code (forgive the rough prototype code): Matrix[] tran = new Matrix[man.model.Bones.Count];// The absolute transforms from the animation player man.model.CopyAbsoluteBoneTransformsTo(tran); Vector3 suitcasePos, suitcaseScale, tempSuitcasePos = new Vector3();// Place holders for the Matrix Decompose Quaternion suitcaseRot = new Quaternion(); // The transformation of the right hand bone is decomposed tran[man.model.Bones["HPF_RightHand"].Index].Decompose(out suitcaseScale, out suitcaseRot, out tempSuitcasePos); suitcasePos = new Vector3(); suitcasePos.X = tempSuitcasePos.Z;// The axes are inverted for some reason suitcasePos.Y = -tempSuitcasePos.Y; suitcasePos.Z = -tempSuitcasePos.X; suitcase.Position = man.Position + suitcasePos;// The actual Suitcase properties suitcase.Rotation = man.Rotation + new Vector3(suitcaseRot.X, suitcaseRot.Y, suitcaseRot.Z); I am also copying the bone transforms from the animation player in the Person class like so: // The transformations from the AnimationPlayer Matrix[] skinTrans = new Matrix[model.Bones.Count]; skinTrans = player.GetBoneTransforms(); // copy each transformation to its corresponding bone for (int i = 0; i < skinTrans.Length; i++) { model.Bones[i].Transform = skinTrans[i]; }

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 25 26 27 28 29 30 31 32 33 34 35 36  | Next Page >