Search Results

Search found 3875 results on 155 pages for 'opengl es lighting'.

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 33/155 | < Previous Page | 29 30 31 32 33 34 35 36 37 38 39 40  | Next Page >

  • Corrupted image if variable is not static

    - by Jaka Jancar
    I'm doing the following: static GLfloat vertices[3][3] = { {0.0, 1.0, 0.0}, {1.0, 0.0, 0.0}, {-1.0, 0.0, 0.0} }; glColor4ub(255, 0, 0, 255); glEnableClientState(GL_VERTEX_ARRAY); glVertexPointer(3, GL_FLOAT, 0, vertices); glDrawArrays(GL_TRIANGLES, 0, 9); glDisableClientState(GL_VERTEX_ARRAY); This works ok: However, if I remove static from vertices and therefore re-create the data on the stack on each rendering, I get the following: This happens both on the simulator and on the device. Should I be keeping the variables around after I call glDrawArrays?

    Read the article

  • OpenGLES - Rendering a background image only once and not wiping it

    - by chaosbeaker
    Hello, first time asking a question here but been watching others answers for a while. My own question is one for improving the performance of my program. Currently I'm wiping the viewFrameBuffer on each pass through my program and then rendering the background image first followed by the rest of my scene. I was wondering how I go about rendering the background image once, and only wiping the rest of the scene for updating/re-rendering. I tried using a seperate buffer but I'm not sure how to present this new buffer to the render buffer. // Set the current EAGLContext and bind to the framebuffer. This will direct all OGL commands to the // framebuffer and the associated renderbuffer attachment which is where our scene will be rendered [EAGLContext setCurrentContext:context]; glBindFramebufferOES(GL_FRAMEBUFFER_OES, viewFramebuffer); // Define the viewport. Changing the settings for the viewport can allow you to scale the viewport // as well as the dimensions etc and so I'm setting it for each frame in case we want to change i glViewport(0, 0, screenBounds.size.width , screenBounds.size.height); // Clear the screen. If we are going to draw a background image then this clear is not necessary // as drawing the background image will destroy the previous image glClearColor(0.0f, 1.0f, 0.0f, 1.0f); glClear(GL_COLOR_BUFFER_BIT); // Setup how the images are to be blended when rendered. This could be changed at different points during your // render process if you wanted to apply different effects glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); switch (currentViewInt) { case 1: { [background render:CGPointMake(240, 0) fromTopLeftBottomRightCenter:@"Bottom"]; // Other Rendering Code }} // Bind to the renderbuffer and then present this image to the current context glBindRenderbufferOES(GL_RENDERBUFFER_OES, viewRenderbuffer); [context presentRenderbuffer:GL_RENDERBUFFER_OES]; Hopefully by solving this I'll also be able to implement another buffer just for rendering particles as I can set them to always use a black background as their alpha source. Any help is greatly appreciated

    Read the article

  • What does setting the GL color before doing a texture mapping operation do?

    - by quixoto
    I am looking at some sample code in a book that creates a jittered antialiasing effect by repeatedly rendering a scene (at different offsets) onto a offscreen texture, then using that texture to repeatedly draw a quad in the main view with some blend stuff set up. To accumulate the color "correctly", the code is setting the color like so: glColor4f(f, f, f, 1); where f is 1.0/number_of_samples, and then binding the offscreen texture and rendering it. Since textures come with their own color and alpha data, what is the effect (mathematically and intuitively) that setting the overall "color" in advance achieves? Thanks.

    Read the article

  • Set brightness, contrass on selected image

    - by Viral
    hi, I want to set brightness and contrast on the image that is selected from the photo library of iphone, is there any way to do the same using/not using open GLES. I've got some code from the developer.apple.com but that is for a single image and i can't use images from photo library, do any one know please let me know how to this. regards viral.

    Read the article

  • How to set image on EAGL VIEW

    - by Viral
    hi, I want to put images from my photo library in to the EAGL view for some further processing. The image that are already in our resources folder will be taken by itself but mltiple or images from photo library can't. So any one knows how to put image on EAGL view in open GLES. Regtards viral

    Read the article

  • Texture repeats even with GL_CLAMP_TO_EDGE set

    - by Lliane
    Hi, i'm trying to put a translucing texture on a face which uses points 1 to 4 (don't mind the numbers) on the following screenshot Sadly as you can see the texture repeats herself in both dimensions, I tried to switch the TEXTURE_WRAP_S from REPEAT to CLAMP_to_EDGE but it doesn't change anything. Texture loading code is here : gl.glBindTexture(gl.GL_TEXTURE_2D, mTexture.get(4)); gl.glActiveTexture(4); gl.glTexParameterf(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MIN_FILTER, gl.GL_LINEAR); gl.glTexParameterf(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MAG_FILTER, gl.GL_LINEAR); gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE); gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE); gl.glTexImage2D(gl.GL_TEXTURE_2D, 0, gl.GL_RGBA, shadowbmp.width, shadowbmp.height, 0, gl.GL_RGBA, gl.GL_UNSIGNED_SHORT_4_4_4_4, shadowbmp.buffer); Texture coordinates are the following : float shadow_bot_text[] = { 0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f, 1.0f }; Thanks

    Read the article

  • How to get X,Y,Z rotations of vertices on a sphere at the origin?

    - by Stoff81
    Hey, I have a sphere in my game world and i would like to place a plane at each vertex on this sphere for debugging purposes. The planes should be orientated so that they lie flat against the sphere (perpendicular to the normals). The sphere is located at the origin, so all the vertices are relative to that. If my thinking is correct, i should be able to do this using the positions of the vertices and some simple trigonometry. I have tried a few combinations but have had no joy yet. I would greatly appreciate some help on this. Thanks. Here is my code: float xRot = RADIANS_TO_DEGREES(sinf(vertex.x/PLANET_RADIUS)); float yRot = RADIANS_TO_DEGREES(cosf(vertex.y/PLANET_RADIUS)); glRotatef(xRot, 1.0, 0, 0); glRotatef(yRot, 0, 1.0, 0);

    Read the article

  • Why don't I need to bind my vertex buffer object before calling glDrawArrays?

    - by valmo
    I'm a bit confused why this still renders. I thought you need to bind a vertex buffer object so that glDrawArrays knows which vertex buffer to use. Here is my initialisation code.. // Create and bind vertex array to store vertex attribute states. glGenVertexArraysOES(NUM_VERTEX_ARRAYS, &m_vertexArray); glBindVertexArrayOES(m_vertexArray); // Create and bind vertex buffer to store vertex data. glGenBuffers(NUM_VERTEX_BUFFERS, &m_vertexBuffer); glBindBuffer(GL_ARRAY_BUFFER, m_vertexBuffer); glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * 36, &m_vertices[0], GL_STATIC_DRAW); glEnableVertexAttribArray(VertexAttribPosition); glVertexAttribPointer(VertexAttribPosition, 3, GL_FLOAT, GL_FALSE, 24, BUFFER_OFFSET(0)); glEnableVertexAttribArray(VertexAttribNormal); glVertexAttribPointer(VertexAttribNormal, 3, GL_FLOAT, GL_FALSE, 24, BUFFER_OFFSET(12)); glBindBuffer(GL_ARRAY_BUFFER, 0); glBindVertexArrayOES(0); Here is my render code. I'm confused why glDrawArrays still works when I bind 0 to GL_ARRAY_BUFFER. glBindVertexArrayOES(m_vertexArray); glBindBuffer(GL_ARRAY_BUFFER, 0); glDrawArrays(GL_TRIANGLES, 0, 36); glBindVertexArrayOES(0);

    Read the article

  • The most efficient method of drawing multiple quads in OpenGL

    - by CPatton
    I'm not very keen with OpenGL and I was wondering if someone could give me some insight on this. I'm a 'seasoned' programmer, I've read the redbook about VBOs and the like, but I was wondering from a more experienced person about the best/most efficient way of achieving this. I've been producing this 2d tile-based game engine to be used in several projects. I have a class called "ScreenObject" which is mainly composed of a Dictionary<Point, Tile> The Point key is to show where to render the Tile on the screen, and the Tile contains one or more textures to be drawn at that point. This ScreenObject is where the tiles will be modified, deleted, added, etc.. My original method of drawing the tiles in the testing I've done was to iterate through the ScreenObject and draw each quad at each location separately. From what I've read, this is a massive waste of resources. It wasn't horribly slow in the testing, but after I've completed the animation classes and effect classes, I'm sure it would be extremely slow. And one last thing, if you wouldn't mind.. As I said before, the Tile class can contain multiple textures to be drawn at the Point location on the screen. I recognize possibly two options for me here. Either add a quad at that location for each texture to be drawn, or, somehow.. use a multiple texture for the same quad (if it's possible). Even if each tile contained one texture only, that would be 64 quads to be drawn on the screen. Most of the tiles will contain 2-5 textures, so the number of total quads would increase dramatically with this method. Would it be feasible to add a quad for each new texture, or am I ignoring a better way to do this? Just need some help understanding this if you don't mind :) I've tried to be as concise as possible, and I'd greatly appreciate any responses.. and even some criticism. Programming is often a learning process and one who develops seems to never stops learning. Thanks for your time.

    Read the article

  • OpenGL 2D Texture Mapping problem.

    - by gutsblow
    Hi there, I am relatively new to OpenGL and I am having some issues when I am rendering an image as a texture for a QUAD which is as the same size of the image. Here is my code. I would be very grateful if someone helps me to solve this problem. The image appears way smaller and is squished. (BTW, the image dimensions are 500x375). glGenTextures( 1, &S_GLator_InputFrameTextureIDSu ); glBindTexture(GL_TEXTURE_2D, S_GLator_InputFrameTextureIDSu); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); glTexImage2D( GL_TEXTURE_2D, 0, 4, S_GLator_EffectCommonData.mRenderBufferWidthSu, S_GLator_EffectCommonData.mRenderBufferHeightSu, 0, GL_RGBA, GL_UNSIGNED_BYTE, dataP); glBindTexture(GL_TEXTURE_2D, S_GLator_InputFrameTextureIDSu); glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, S_GLator_EffectCommonData.mRenderBufferWidthSu, S_GLator_EffectCommonData.mRenderBufferHeightSu, GL_RGBA, GL_UNSIGNED_BYTE, bufferP); //set the matrix modes glMatrixMode( GL_PROJECTION ); glLoadIdentity(); //gluPerspective( 45.0, (GLdouble)widthL / heightL, 0.1, 100.0 ); glOrtho (0, 1, 0, 1, -1, 1); // Set up the frame-buffer object just like a window. glViewport( 0, 0, widthL, heightL ); glDisable(GL_DEPTH_TEST); glClearColor( 0.0f, 0.0f, 0.0f, 0.0f ); glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); glBindTexture( GL_TEXTURE_2D, S_GLator_InputFrameTextureIDSu ); //Render the geometry to the frame-buffer object glBegin(GL_QUADS); //input frame glColor4f(1.f,1.f,1.f,1.f); glTexCoord2f(0.0f,0.0f); glVertex3f(0.f ,0.f ,0.0f); glTexCoord2f(1.0f,0.0f); glVertex3f(1.f ,0.f,0.0f); glTexCoord2f(1.0f,1.f); glVertex3f(1.f ,1.f,0.0f); glTexCoord2f(0.0f,1.f); glVertex3f(0.f ,1.f,0.0f); glEnd();

    Read the article

  • OpenGL Polygon Stipple Not Working On Different Machine

    - by FranticPedantic
    I have a situation where I am trying to draw a semi-transparent rectangle over a background that is not using openGL and so I can not use blending. I decided to use polygon stippling for a 'screen door transparency' effect as recommended by some. It works fine on my machine and some others, but on some machines with slightly old Intel graphics cards it's failing to render the rectangle at all. If I turn off polygon stipple, it renders fine (but without the stipple). I have compared many of the state variables that I thought might affect it (see code) between machines and they are all the same, and I get no errors. static const GLubyte stipplePatternChkr[128]; //definition omitted for clarity //but works on my machine // stipple the box glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); glColor4ubv(Color(COLORREF_PADGRAY)); glEnable(GL_POLYGON_STIPPLE); glPolygonStipple(stipplePatternChkr); CRect rcStipple(dim); rcStipple.DeflateRect(padding - 1, padding - 1); glBegin(GL_QUADS); glVertex2i(rcStipple.left, rcStipple.bottom); glVertex2i(rcStipple.right, rcStipple.bottom); glVertex2i(rcStipple.right, rcStipple.top); glVertex2i(rcStipple.left, rcStipple.top); glEnd(); glDisable(GL_POLYGON_STIPPLE); int err = glGetError(); if (err != GL_NO_ERROR) { TRACE("glError(%s: %s)\n", s, gluErrorString(err)); } float x; glGetFloatv(GL_UNPACK_ALIGNMENT, &x); TRACE("unpack alignment %f\n", x); glGetFloatv(GL_UNPACK_IMAGE_HEIGHT, &x); TRACE("unpack height %f\n", x); glGetFloatv(GL_UNPACK_LSB_FIRST, &x); TRACE("unpack lsb %f\n", x); glGetFloatv(GL_UNPACK_ROW_LENGTH, &x); TRACE("unpack length %f\n", x); glGetFloatv(GL_UNPACK_SKIP_PIXELS, &x); TRACE("upnack skip %f\n", x); glGetFloatv(GL_UNPACK_SWAP_BYTES, &x); TRACE("upnack swap %f\n", x);

    Read the article

  • OpenGL, problems with GL_MODELVIEW GL_PROJECTION...

    - by Marcos Roriz
    Guys, I'm trying to finish up my homework but I'm having some problems here on these models on openGL... any Idea why is my draw not happening? One thing that strange is that if I change to gluPerspective it works.. #include <GL/glut.h> #include <stdlib.h> #include <stdio.h> static int shoulder = 0; static int elbow = 0; void init(void) { glClearColor(1.0, 1.0, 1.0, 0.0); } void display(void) { glClear(GL_COLOR_BUFFER_BIT); glPushMatrix(); /* BASE */ glRotatef((GLfloat) shoulder, 0.0, 0.0, 1.0); glTranslatef(1.0, 0.0, 0.0); glPushMatrix(); //glScalef(2.0, 0.4, 1.0); glBegin(GL_QUADS); glColor3f(0, 0, 0); glVertex2f(0.0, 0.0); glVertex2f(0.0, 10.0); glVertex2f(10.0, 10.0); glVertex2f(10.0, 0.0); glEnd(); glPopMatrix(); glPopMatrix(); glutSwapBuffers(); } void reshape(int w, int h) { glViewport(0, 0, (GLsizei) w, (GLsizei) h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho((GLfloat)-w/2, (GLfloat)w/2, (GLfloat)-h/2, (GLfloat)h/2, -1.0, 1.0); // modo de projecao ortogonal glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslatef(0.0, 0.0, -5.0); } void keyboard(unsigned char key, int x, int y) { switch (key) { case 's': shoulder = (shoulder + 5) % 360; glutPostRedisplay(); break; case 'S': shoulder = (shoulder - 5) % 360; glutPostRedisplay(); break; case 'e': elbow = (elbow + 5) % 360; glutPostRedisplay(); break; case 'E': elbow = (elbow - 5) % 360; glutPostRedisplay(); break; case 27: exit(0); break; default: break; } } int main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB); glutInitWindowSize(800, 400); glutInitWindowPosition(100, 100); glutCreateWindow(argv[0]); init(); glutDisplayFunc(display); glutReshapeFunc(reshape); glutKeyboardFunc(keyboard); glutMainLoop(); return 0; }

    Read the article

  • Flipping OpenGL texture

    - by Mk12
    When I load textures from images normally, they are upside down because of OpenGL's coordinate system. What would be the best way to flip them? glScalef(1.0f, -1.0f, 1.0f); vertically flipping the image files manually (in Photoshop) flipping them programatically after loading them (I don't know how) This is the method I'm using to load png textures, in my Utilities.m file (Objective-C): + (GLuint)loadPngTexture:(NSString *)name { CFURLRef textureURL = CFBundleCopyResourceURL( CFBundleGetMainBundle(), (CFStringRef)name, CFSTR("png"), CFSTR("Textures")); NSAssert(textureURL, @"Texture name invalid"); CGImageSourceRef imageSource = CGImageSourceCreateWithURL(textureURL, NULL); NSAssert(imageSource, @"Invalid Image Path."); NSAssert((CGImageSourceGetCount(imageSource) > 0), @"No Image in Image Source."); CFRelease(textureURL); CGImageRef image = CGImageSourceCreateImageAtIndex(imageSource, 0, NULL); NSAssert(image, @"Image not created."); CFRelease(imageSource); NSUInteger width = CGImageGetWidth(image); NSUInteger height = CGImageGetHeight(image); void *data = malloc(width * height * 4); CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); NSAssert(colorSpace, @"Colorspace not created."); CGContextRef context = CGBitmapContextCreate( data, width, height, 8, width * 4, colorSpace, kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host); NSAssert(context, @"Context not created."); CGColorSpaceRelease(colorSpace); CGContextDrawImage(context, CGRectMake(0, 0, width, height), image); CGImageRelease(image); CGContextRelease(context); GLuint textureId; glGenTextures(1, &textureId); glBindTexture(GL_TEXTURE_2D, textureId); glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP_SGIS, GL_TRUE); glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, data); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE_SGIS); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE_SGIS); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); free(data); return textureId; } Also, another thing I was wondering about: If I made a simple 2d game, with pixels mapped to units, would it be alright to set it up so that the origin is in the top-left corner, or would I run in to problems with other things (e.g. text rendering)? Thanks.

    Read the article

  • iPhone OpenGL scrolling background jumps when texture is drawn for first time

    - by Magnum39
    I have been fighting a problem for a while now and would appreciate any help anybody could give. I have a sprite that moves within a landscape. The sprite remains in the center of the screen and the background moves to simulate that the sprite is moving within the landscape. I have split the landscape into sections so that I only draw the sections of the landscape that I need (are on screen). The Problem: As a new texture section of the screen appears on the screen (is drawn for the first time) the movement jumps. Almost like a frame is missed. I have done some timing experiments and I do not thinks a frame is missed. My processing is well below the 30fps that I have the animation set to. It only happens the first time the texture section is drawn. Is there something extra that is done the first time a texture is drawn? Here is the code: - (void) render{ // Sets up an array of values to use as the sprite vertices. const GLfloat sVerts[] = { -1.6f, -1.6f, 1.6f, -1.6f, -1.6f, 1.6f, 1.6f, 1.6f, }; static const GLfloat sTexCoords[] = { 0.0, 1.0, 1.0, 1.0, 0.0, 0.0, 1.0, 0.0 }; glDisableClientState(GL_COLOR_ARRAY); glEnableClientState(GL_VERTEX_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY); // Setup opengl to draw the object in correct orientation, size, position, etc glLoadIdentity(); // Enable use of the texture glEnable(GL_TEXTURE_2D); glVertexPointer(2, GL_FLOAT, 0, sVerts); glTexCoordPointer(2, GL_FLOAT, 0, sTexCoords); // draw the texture // set the position of the first tile float xOffset = -4.8; float yOffset = 4.8; int i; int y; int currentTexture = textureA; for(i=0; i<2; i++) { for(y=0; y<2; y++) { // test for the texture tile on the screen if not on screen then do not draw float localX = xOffset+(3.21*y); float localY = yOffset-(3.21*i); float xDiff = monkeyX - localX; float yDiff = monkeyY - localY; if(((xDiff < 3.2) && (xDiff > -3.2)) && ((yDiff <2.7) && (yDiff > -2.7))) { // bind the texture and set the vertex data pointers glBindTexture(GL_TEXTURE_2D, spriteTexture[currentTexture]); // move to draw position for the texture glLoadIdentity(); glTranslatef((localX+self.positionX), (localY+self.positionY), 0.0); //draw the texture glDrawArrays(GL_TRIANGLE_STRIP, 0, 4); } currentTexture++; } } }

    Read the article

  • Problem with Freetype and OpenGL

    - by Morgan
    Hey, i'm having a weird issue with drawing text in openGL loaded with the Freetype 2 library. Here is a screenshot of what I'm seeing. http://img203.imageshack.us/img203/3316/freetypeweird.png Here are my code bits for loading and rendering my text. class Font { Font(const String& filename) { if (FT_New_Face(Font::ftLibrary, "arial.ttf", 0, &mFace)) { cout << "UH OH!" << endl; } FT_Set_Char_Size(mFace, 16 * 64, 16 * 64, 72, 72); } Glyph* GetGlyph(const unsigned char ch) { if(FT_Load_Char(mFace, ch, FT_LOAD_RENDER)) cout << "OUCH" << endl; FT_Glyph glyph; if(FT_Get_Glyph( mFace->glyph, &glyph )) cout << "OUCH" << endl; FT_BitmapGlyph bitmap_glyph = (FT_BitmapGlyph)glyph; Glyph* thisGlyph = new Glyph; thisGlyph->buffer = bitmap_glyph->bitmap.buffer; thisGlyph->width = bitmap_glyph->bitmap.width; thisGlyph->height = bitmap_glyph->bitmap.rows; return thisGlyph; } }; The relevant glyph information (width, height, buffer) is stored in the following struct struct Glyph { GLubyte* buffer; Uint width; Uint height; }; And finally, to render it, I have this class called RenderFont. class RenderFont { RenderFont(Font* font) { mTextureIds = new GLuint[128]; mFirstDisplayListId=glGenLists(128); glGenTextures( 128, mTextureIds ); for(unsigned char i=0;i<128;i++) { MakeDisplayList(font, i); } } void MakeDisplayList(Font* font, unsigned char ch) { Glyph* glyph = font->GetGlyph(ch); glBindTexture( GL_TEXTURE_2D, mTextureIds[ch]); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, glyph->width, glyph->height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, glyph->buffer); glNewList(mFirstDisplayListId+ch,GL_COMPILE); glBindTexture(GL_TEXTURE_2D, mTextureIds[ch]); glBegin(GL_QUADS); glTexCoord2d(0,1); glVertex2f(0,glyph->height); glTexCoord2d(0,0); glVertex2f(0,0); glTexCoord2d(1,0); glVertex2f(glyph->width,0); glTexCoord2d(1,1); glVertex2f(glyph->width,glyph->height); glEnd(); glTranslatef(16, 0, 0); glEndList(); } void Draw(const String& text, Uint size, const TransformComponent* transform, const Color32* color) { glEnable(GL_TEXTURE_2D); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glTranslatef(100, 250, 0.0f); glListBase(mFirstDisplayListId); glCallLists(text.length(), GL_UNSIGNED_BYTE, text.c_str()); glDisable(GL_TEXTURE_2D); glDisable(GL_BLEND); glLoadIdentity(); } private: GLuint mFirstDisplayListId; GLuint* mTextureIds; }; Can anybody see anything weird going on here that would cause the garbled text? It's strange because if I change the font size, or the DPI, then some of the letters that display correctly become garbled, and other letters that were garbled before then display correctly.

    Read the article

  • opengl, Black lines in-between tiles

    - by MiJyn
    When its translated in an integral value (1,2,3, etc....), there are no black lines in-between the tiles, it looks fine. But when it's translated to a non-integral (1.1, 1.5, 1.67), there are small blackish lines between each tile (I'm imagining that it's due to subpixel rendering, right?) ... and it doesn't look pretty =P So... what should I do? This is my image-loading code, by the way: bool Image::load_opengl() { this->id = 0; glGenTextures(1, &this->id); this->bind(); // Parameters... TODO: Should we change this? glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, this->size.x, this->size.y, 0, GL_BGRA, GL_UNSIGNED_BYTE, (void*) FreeImage_GetBits(this->data)); this->unbind(); return true; } I've also tried using: glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP); and: glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); Here is my image drawing code: void Image::draw(Pos pos, CROP crop, SCALE scale) { if (!this->loaded || this->id == 0) { return; } // Start position & size Pos s_p; Pos s_s; // End size Pos e_s; if (crop.active) { s_p = crop.pos / this->size; s_s = crop.size / this->size; //debug("%f %f", s_s.x, s_s.y); s_s = s_s + s_p; s_s.clamp(1); //debug("%f %f", s_s.x, s_s.y); } else { s_s = 1; } if (scale.active) { e_s = scale.size; } else if (crop.active) { e_s = crop.size; } else { e_s = this->size; } // FIXME: Is this okay? s_p.y = 1 - s_p.y; s_s.y = 1 - s_s.y; // TODO: Make this use VAO/VBO's!! glPushMatrix(); glTranslate(pos.x, pos.y, 0); this->bind(); glBegin(GL_QUADS); glTexCoord2(s_p.x, s_p.y); glVertex2(0, 0); glTexCoord2(s_s.x, s_p.y); glVertex2(e_s.x, 0); glTexCoord2(s_s.x, s_s.y); glVertex2(e_s.x, e_s.y); glTexCoord2(s_p.x, s_s.y); glVertex2(0, e_s.y); glEnd(); this->unbind(); glPopMatrix(); } OpenGL Initialization code: void game__gl_init() { glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluOrtho2D(0.0, config.window.size.x, config.window.size.y, 0.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glDisable(GL_DEPTH_TEST); glEnable(GL_BLEND); glEnable(GL_TEXTURE_2D); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); } Screenshots of the issue:

    Read the article

  • OpenGL polygons stuck at top left?

    - by user146780
    I'm using theallegro library and through it OpenGL. I enable depth testing, then upon resize I do: glEnable(GL_CULL_FACE); glCullFace(GL_BACK); glEnable(GL_DEPTH_TEST); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glFrustum(0,event.display.width,event.display.height,0,1,300); Then my drawing looks like: float BOX_SIZE = 200.0f; glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glRotatef(0.5, 0, 0.0f, 1.0f); glBegin(GL_QUADS); //Top face glColor3f(1.0f, 1.0f, 0.0f); glNormal3f(0.0, 1.0f, 0.0f); glVertex3f(500 + -BOX_SIZE / 2, BOX_SIZE / 2, -BOX_SIZE / 2); glVertex3f(500 + -BOX_SIZE / 2, BOX_SIZE / 2, BOX_SIZE / 2); glVertex3f(500 + BOX_SIZE / 2, BOX_SIZE / 2, BOX_SIZE / 2); glVertex3f(500 + BOX_SIZE / 2, BOX_SIZE / 2, -BOX_SIZE / 2); //Bottom face glColor3f(1.0f, 0.0f, 1.0f); glNormal3f(0.0, -1.0f, 0.0f); glVertex3f(-BOX_SIZE / 2, -BOX_SIZE / 2, -BOX_SIZE / 2); glVertex3f(BOX_SIZE / 2, -BOX_SIZE / 2, -BOX_SIZE / 2); glVertex3f(BOX_SIZE / 2, -BOX_SIZE / 2, BOX_SIZE / 2); glVertex3f(-BOX_SIZE / 2, -BOX_SIZE / 2, BOX_SIZE / 2); //Left face glNormal3f(-1.0, 0.0f, 0.0f); glColor3f(0.0f, 1.0f, 1.0f); glVertex3f(-BOX_SIZE / 2, -BOX_SIZE / 2, -BOX_SIZE / 2); glVertex3f(-BOX_SIZE / 2, -BOX_SIZE / 2, BOX_SIZE / 2); glColor3f(0.0f, 0.0f, 1.0f); glVertex3f(-BOX_SIZE / 2, BOX_SIZE / 2, BOX_SIZE / 2); glVertex3f(-BOX_SIZE / 2, BOX_SIZE / 2, -BOX_SIZE / 2); //Right face glNormal3f(1.0, 0.0f, 0.0f); glColor3f(1.0f, 0.0f, 0.0f); glVertex3f(BOX_SIZE / 2, -BOX_SIZE / 2, -BOX_SIZE / 2); glVertex3f(BOX_SIZE / 2, BOX_SIZE / 2, -BOX_SIZE / 2); glColor3f(0.0f, 1.0f, 0.0f); glVertex3f(BOX_SIZE / 2, BOX_SIZE / 2, BOX_SIZE / 2); glVertex3f(BOX_SIZE / 2, -BOX_SIZE / 2, BOX_SIZE / 2); glEnd(); glEnable(GL_TEXTURE_2D); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glColor3f(1.0f, 1.0f, 1.0f); glBegin(GL_QUADS); //Front face glNormal3f(0.0, 0.0f, 1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-BOX_SIZE / 2, -BOX_SIZE / 2, BOX_SIZE / 2); glTexCoord2f(1.0f, 0.0f); glVertex3f(BOX_SIZE / 2, -BOX_SIZE / 2, BOX_SIZE / 2); glTexCoord2f(1.0f, 1.0f); glVertex3f(BOX_SIZE / 2, BOX_SIZE / 2, BOX_SIZE / 2); glTexCoord2f(0.0f, 1.0f); glVertex3f(-BOX_SIZE / 2, BOX_SIZE / 2, BOX_SIZE / 2); //Back face glNormal3f(0.0, 0.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-BOX_SIZE / 2, -BOX_SIZE / 2, -BOX_SIZE / 2); glTexCoord2f(1.0f, 0.0f); glVertex3f(-BOX_SIZE / 2, BOX_SIZE / 2, -BOX_SIZE / 2); glTexCoord2f(1.0f, 1.0f); glVertex3f(BOX_SIZE / 2, BOX_SIZE / 2, -BOX_SIZE / 2); glTexCoord2f(0.0f, 1.0f); glVertex3f(BOX_SIZE / 2, -BOX_SIZE / 2, -BOX_SIZE / 2); glEnd(); glDisable(GL_TEXTURE_2D); //code goes here al_flip_display(); for some reason the cube no matter how I translate it seems to extend from 0,0 and theres always a vertex at 0,0. What have I done wrong? Thanks

    Read the article

  • opengl 3d texture issue

    - by user1478217
    Hi i'm trying to use a 3d texture in opengl to implement volume rendering. Each voxel has an rgba colour value and is currently rendered as a screen facing quad.(for testing purposes). I just can't seem to get the sampler to give me a colour value in the shader. The quads always end up black. When I change the shader to generate a colour (based on xyz coords) then it works fine. I'm loading the texture with the following code: glGenTextures(1, &tex3D); glBindTexture(GL_TEXTURE_3D, tex3D); unsigned int colours[8]; colours[0] = Colour::AsBytes<unsigned int>(Colour::Blue); colours[1] = Colour::AsBytes<unsigned int>(Colour::Red); colours[2] = Colour::AsBytes<unsigned int>(Colour::Green); colours[3] = Colour::AsBytes<unsigned int>(Colour::Magenta); colours[4] = Colour::AsBytes<unsigned int>(Colour::Cyan); colours[5] = Colour::AsBytes<unsigned int>(Colour::Yellow); colours[6] = Colour::AsBytes<unsigned int>(Colour::White); colours[7] = Colour::AsBytes<unsigned int>(Colour::Black); glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA, 2, 2, 2, 0, GL_RGBA, GL_UNSIGNED_BYTE, colours); The colours array contains the correct data, i.e. the first four bytes have values 0, 0, 255, 255 for blue. Before rendering I bind the texture to the 2nd texture unit like so: glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_3D, tex3D); And render with the following code: shaders["DVR"]->Use(); shaders["DVR"]->Uniforms["volTex"].SetValue(1); shaders["DVR"]->Uniforms["World"].SetValue(Mat4(vl_one)); shaders["DVR"]->Uniforms["viewProj"].SetValue(cam->GetViewTransform() * cam->GetProjectionMatrix()); QuadDrawer::DrawQuads(8); I have used these classes for setting shader params before and they work fine. The quaddrawer draws eight instanced quads. The vertex shader code looks like this: #version 330 layout(location = 0) in vec2 position; layout(location = 1) in vec2 texCoord; uniform sampler3D volTex; ivec3 size = ivec3(2, 2, 2); uniform mat4 World; uniform mat4 viewProj; smooth out vec4 colour; void main() { vec3 texCoord3D; int num = gl_InstanceID; texCoord3D.x = num % size.x; texCoord3D.y = (num / size.x) % size.y; texCoord3D.z = (num / (size.x * size.y)); texCoord3D /= size; texCoord3D *= 2.0; texCoord3D -= 1.0; colour = texture(volTex, texCoord3D); //colour = vec4(texCoord3D, 1.0); gl_Position = viewProj * World * vec4(texCoord3D, 1.0) + (vec4(position.x, position.y, 0.0, 0.0) * 0.05); } uncommenting the line where I set the colour value equal to the texcoord works fine, and makes the quads coloured. The fragment shader is simply: #version 330 smooth in vec4 colour; out vec4 outColour; void main() { outColour = colour; } So my question is, what am I doing wrong, why is the sampler not getting any colour values from the 3d texture? [EDIT] Figured it out but can't self answer (new user): As soon as I posted this I figured it out, I'll put the answer up to help anyone else (it's not specifically a 3d texture issue, and i've also fallen afoul of it before, D'oh!). I didn't generate mipmaps for the texture, and the default magnification/minification filters weren't set to either GL_LINEAR, or GL_NEAREST. Boom! no textures. Same thing happens with 2d textures.

    Read the article

  • opengl - Rendering multiple cubes

    - by opiop65
    I have this code (Doesn't work at all) static void initGl() { glViewport(0, 0, Display.getWidth(), Display.getHeight()); glMatrixMode(GL_PROJECTION); glLoadIdentity(); GLU.gluPerspective(45.0f, Display.getWidth() / Display.getHeight(), 1.0f, 1000.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glClearColor(0.0f, 0.0f, 0.0f, 0.0f); glClearDepth(1.0f); glDepthFunc(GL_LEQUAL); glEnable(GL_DEPTH_TEST); glShadeModel(GL_SMOOTH); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); } public static void renderGL() { glViewport(0, 0, Display.getWidth(), Display.getHeight()); glClearColor(0.0f, 0.0f, 0.0f, 0.5f); glLoadIdentity(); glTranslatef(0.0f, 0.0f, -60.0f); drawCube(); } public static void drawCube() { for (int x = 0; x < 100; x++) { for (int y = 0; y < 100; y++) { for (int z = 0; z < 100; z++) { glBegin(GL_QUADS); glColor3f(1, 0, 0); glVertex3f(-x, -y, z); glVertex3f(x, -y, z); glVertex3f(x, y, z); glVertex3f(-x, y, z); glColor3f(1, 0, 1); glVertex3f(x, -y, -z); glVertex3f(-x, -y, -z); glVertex3f(-x, y, -z); glVertex3f(x, y, -z); glColor3f(1, 1, 1); glVertex3f(-x, y, z); glVertex3f(x, y, z); glVertex3f(x, y, -z); glVertex3f(-x, y, -z); glColor3f(0, 0, 1); glVertex3f(x, -y, z); glVertex3f(-x, -y, z); glVertex3f(-x, -y, -z); glVertex3f(x, -y, -z); glColor3f(1, 1, 0); glVertex3f(x, -y, z); glVertex3f(x, -y, -z); glVertex3f(x, y, -z); glVertex3f(x, y, z); glColor3f(0, 2, 1); glVertex3f(-x, -y, -z); glVertex3f(-x, -y, z); glVertex3f(-x, y, z); glVertex3f(-x, y, -z); glEnd(); } } } All it does it freeze up the program and eventually it will render the red side of the cube. This obviously has to do with gltranslatef, but I don't know why that isn't working. My question is, how do I render multiple cubes at once? Are there any tutorials out there on voxel engines? Sorry for the horrible code, I realize I probably need a array to do this. I'm quite new at opengl.

    Read the article

  • gluCylinder() how works OpenGL

    - by amin__
    I wanted to build a cricket ground with OpenGL. I made several polygons to indicate field, pitch and bowling lines. But the problem is when I am trying to use gluCylinder to make stumps I made depth glEnable(GL_DEPTH_TEST), but my polygons are then not working. I just want to know how Can I use gluCylinder to make stumps with those polygons I have made. I have following code, but want to add stumps here but I cant, #include <GL/gl.h> #include <GL/glut.h> static double deg=0.0; void display(void) { glClear (GL_COLOR_BUFFER_BIT); glRotatef(deg, 0.0, 0.0, 1.0); // Rotate by deg // field glColor3f (0.0, 0.5, 0.0); glBegin(GL_POLYGON); glVertex3f (0, 0, 0.0); glVertex3f (1, 0, 0.0); glVertex3f (1, 0.75, 0.0); glVertex3f (0.8, 0.82, 0.0); glVertex3f (0.6, 0.85, 0.0); glVertex3f (0.4, 0.85, 0.0); glVertex3f (0.2, 0.82, 0.0); glVertex3f (0.0, 0.75, 0.0); glEnd(); // pitch glColor3f (0.25, 0.30, 0.0); glBegin(GL_POLYGON); glVertex3f(0.5,0.65,0.0); glVertex3f(0.47,0.35,0.0); glVertex3f(0.60,0.35,0.0); glVertex3f(0.57,0.65,0.0); glEnd(); //ump line glColor3f (1.0, 1.0, 1.0); glBegin(GL_POLYGON); glVertex3f(0.49,0.63,0.0); glVertex3f(0.49,0.6315,0.0); glVertex3f(0.58,0.6315,0.0); glVertex3f(0.58,0.63,0.0); glEnd(); //bat line glColor3f (1.0, 1.0, 1.0); glBegin(GL_POLYGON); glVertex3f(0.46,0.40,0.0); glVertex3f(0.46,0.4025,0.0); glVertex3f(0.61,0.4025,0.0); glVertex3f(0.61,0.40,0.0); glEnd(); glFlush (); } void init (void) { glClearColor (0.0, 0.0, 0.0, 0.0); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho(0.0, 1.0, 0.0, 1.0, -1.0, 1.0); } void keyboard(unsigned char key, int x, int y) { switch (key) { case 27: // "esc" on keyboard exit(0); break; case 97: // "a" on keyboard deg = deg+5.0; glutPostRedisplay(); break; case 100: deg = deg-5.0; glutPostRedisplay(); break; } } int main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB); glutInitWindowSize (600, 600); glutInitWindowPosition (100, 100); glutCreateWindow ("hello"); init (); glutDisplayFunc(display); glutKeyboardFunc(keyboard); glutMainLoop(); return 0; }

    Read the article

  • OpenGL true coordinates and glutTimerFunc() problem C++

    - by Meko
    HI I am starting to learn openGl for C++.but at stating point I stucked. I have 2 question that is the coordinates for drawing some objects? I mean where is X, Y and Z? Second one I am making tutorial from some sites. and I am trying to animate my triangle.In tutorial it works but on my computer not.I Also downloaded source codes but It doesnt move. Here sample codes. I thougt that problem is glutTimerFunc(). #include #include #ifdef APPLE #include #include #else #include #endif using namespace std; //Called when a key is pressed void handleKeypress(unsigned char key, int x, int y) { switch (key) { case 27: //Escape key exit(0); } } //Initializes 3D rendering void initRendering() { glEnable(GL_DEPTH_TEST); } //Called when the window is resized void handleResize(int w, int h) { glViewport(0, 0, w, h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.0, (double)w / (double)h, 1.0, 200.0); } float _angle = 30.0f; float _cameraAngle = 0.0f; //Draws the 3D scene void drawScene() { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glMatrixMode(GL_MODELVIEW); //Switch to the drawing perspective glLoadIdentity(); //Reset the drawing perspective glRotatef(-_cameraAngle, 0.0f, 1.0f, 0.0f); //Rotate the camera glTranslatef(0.0f, 0.0f, -5.0f); //Move forward 5 units glPushMatrix(); //Save the transformations performed thus far glTranslatef(0.0f, -1.0f, 0.0f); //Move to the center of the trapezoid glRotatef(_angle, 0.0f, 0.0f, 1.0f); //Rotate about the z-axis glBegin(GL_QUADS); //Trapezoid glVertex3f(-0.7f, -0.5f, 0.0f); glVertex3f(0.7f, -0.5f, 0.0f); glVertex3f(0.4f, 0.5f, 0.0f); glVertex3f(-0.4f, 0.5f, 0.0f); glEnd(); glPopMatrix(); //Undo the move to the center of the trapezoid glPushMatrix(); //Save the current state of transformations glTranslatef(1.0f, 1.0f, 0.0f); //Move to the center of the pentagon glRotatef(_angle, 0.0f, 1.0f, 0.0f); //Rotate about the y-axis glScalef(0.7f, 0.7f, 0.7f); //Scale by 0.7 in the x, y, and z directions glBegin(GL_TRIANGLES); //Pentagon glVertex3f(-0.5f, -0.5f, 0.0f); glVertex3f(0.5f, -0.5f, 0.0f); glVertex3f(-0.5f, 0.0f, 0.0f); glVertex3f(-0.5f, 0.0f, 0.0f); glVertex3f(0.5f, -0.5f, 0.0f); glVertex3f(0.5f, 0.0f, 0.0f); glVertex3f(-0.5f, 0.0f, 0.0f); glVertex3f(0.5f, 0.0f, 0.0f); glVertex3f(0.0f, 0.5f, 0.0f); glEnd(); glPopMatrix(); //Undo the move to the center of the pentagon glPushMatrix(); //Save the current state of transformations glTranslatef(-1.0f, 1.0f, 0.0f); //Move to the center of the triangle glRotatef(_angle, 1.0f, 2.0f, 3.0f); //Rotate about the the vector (1, 2, 3) glBegin(GL_TRIANGLES); //Triangle glVertex3f(0.5f, -0.5f, 0.0f); glVertex3f(0.0f, 0.5f, 0.0f); glVertex3f(-0.5f, -0.5f, 0.0f); glEnd(); glPopMatrix(); //Undo the move to the center of the triangle glutSwapBuffers(); } void update(int value) { _angle += 2.0f; if (_angle 360) { _angle -= 260; } glutPostRedisplay(); //Tell GLUT that the display has changed //Tell GLUT to call update again in 25 milliseconds glutTimerFunc(25, update, 0); } int main(int argc, char** argv) { //Initialize GLUT glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); glutInitWindowSize(400, 400); //Create the window glutCreateWindow("Transformations and Timers - videotutorialsrock.com"); initRendering(); //Set handler functions glutDisplayFunc(drawScene); glutKeyboardFunc(handleKeypress); glutReshapeFunc(handleResize); glutTimerFunc(24, update, 0); //Add a timer glutMainLoop(); return 0; }

    Read the article

  • SDL+OpenGL app: blank screen

    - by Lococo
    I spent the last three days trying to create a small app using SDL + OpenGL. The app itself runs fine -- except it never outputs any graphics; just a black screen. I've condensed it down to a minimal C file, and I'm hoping someone can give me some guidance. I'm running out of ideas. I'm using Windows Vista, MinGW & MSYS. Thanks in advance for any advice! #include <SDL/SDL.h> #include <SDL_opengl.h> size_t sx=600, sy=600, bpp=32; void render(void) { glEnable(GL_DEPTH_TEST); // enable depth testing glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // clear to black glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // clear color/depth buffer glLoadIdentity(); // reset modelview matrix glColor3b(255, 0, 0); // red glLineWidth(3.0); // line width=3 glRecti(10, 10, sx-10, sy-10); // draw rectangle glFlush(); SDL_GL_SwapBuffers(); } int input(void) { SDL_Event event; while (SDL_PollEvent(&event)) if (event.type == SDL_QUIT || (event.type == SDL_KEYUP && event.key.keysym.sym == SDLK_ESCAPE)) return 0; return 1; } int main(int argc, char *argv[]) { SDL_Surface* surf; if (SDL_Init(SDL_INIT_EVERYTHING) != 0) return 0; if (!(surf = SDL_SetVideoMode(sx, sy, bpp, SDL_HWSURFACE|SDL_DOUBLEBUF))) return 0; glViewport(0, 0, sx, sy); // reset the viewport to new dimensions glMatrixMode(GL_PROJECTION); // set projection matrix to be current glLoadIdentity(); // reset projection matrix glOrtho(0, sx, sy, 0, -1.0, 1.0); // create ortho view glMatrixMode(GL_MODELVIEW); // set modelview matrix glLoadIdentity(); // reset modelview matrix for (;;) { if (!input()) break; render(); SDL_Delay(10); } SDL_FreeSurface(surf); SDL_Quit(); exit(0); } UPDATE: I have a version that works, but it changes orthographic to perspective. I'm not sure why this works and the other doesn't, but for future reference, here's a version that works: #include <SDL/SDL.h> #include <SDL_opengl.h> size_t sx=600, sy=600, bpp=32; void render(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); // set location in front of camera glTranslated(0, 0, -10); glBegin(GL_QUADS); // draw a square glColor3d(1, 0, 0); glVertex3d(-2, 2, 0); glVertex3d( 2, 2, 0); glVertex3d( 2, -2, 0); glVertex3d(-2, -2, 0); glEnd(); glFlush(); SDL_GL_SwapBuffers(); } int input(void) { SDL_Event event; while (SDL_PollEvent(&event)) if (event.type == SDL_QUIT || (event.type == SDL_KEYUP && event.key.keysym.sym == SDLK_ESCAPE)) return 0; return 1; } int main(int argc, char *argv[]) { SDL_Surface *surf; if (SDL_Init(SDL_INIT_EVERYTHING) != 0) return 0; if (!(surf = SDL_SetVideoMode(sx, sy, bpp, SDL_OPENGL))) return 0; glViewport(0, 0, sx, sy); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.0, (float)sx / (float)sy, 1.0, 100.0); glMatrixMode(GL_MODELVIEW); glClearColor(0, 0, 0, 1); glClearDepth(1.0); glEnable(GL_DEPTH_TEST); for (;;) { if (!input()) break; render(); SDL_Delay(10); } SDL_FreeSurface(surf); SDL_Quit(); return 0; }

    Read the article

  • Painting with pixel shaders

    - by Gustavo Maciel
    I have an almost full understanding of how 2D Lighting works, saw this post and was tempted to try implementing this in HLSL. I planned to paint each of the layers with shaders, and then, combine them just drawing one on top of another, or just pass the 3 textures to the shader and getting a better way to combine them. Working almost as planned, but I got a little question in the matter. I'm drawing each layer this way: GraphicsDevice.SetRenderTarget(lighting); GraphicsDevice.Clear(Color.Transparent); //... Setup shader SpriteBatch.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend, SamplerState.LinearClamp, DepthStencilState.None, RasterizerState.CullNone, lightingShader); SpriteBatch.Draw(texture, fullscreen, Color.White); SpriteBatch.End(); GraphicsDevice.SetRenderTarget(darkMask); GraphicsDevice.Clear(Color.Transparent); //... Setup shader SpriteBatch.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend, SamplerState.LinearClamp, DepthStencilState.None, RasterizerState.CullNone, darkMaskShader); SpriteBatch.Draw(texture, fullscreen, Color.White); SpriteBatch.End(); Where lightingShader and darkMaskShader are shaders that, with parameters (view and proj matrices, light pos, color and range, etc) generate a texture meant to be that layer. It works fine, but I'm not sure if drawing a transparent quad on top of a transparent render target is the best way of doing it. Because I actually just need the position and params. Concluding: Can I paint a texture with shaders without having to clear it and then draw a transparent texture on top of it?

    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 | 29 30 31 32 33 34 35 36 37 38 39 40  | Next Page >