How can data not be 1-byte aligned? This strongly suggests a lack of understanding of what the row alignment in pixel transfer operations means. Image data that you pass to OpenGL is expected to be grouped into rows. Each row contains width number of pixels, with each pixel being the size as defined by the … Read more
I haven’t test the following but i will decompose the conversion in 3 steps: Extract info for your image: UIImage* image = [UIImage imageNamed:@”imageToApplyAsATexture.png”]; CGImageRef imageRef = [image CGImage]; int width = CGImageGetWidth(imageRef); int height = CGImageGetHeight(imageRef); Allocate a textureData with the above properties: GLubyte* textureData = (GLubyte *)malloc(width * height * 4); // if … Read more
You have a couple of choices: You can mix the images on the javascript side using canvas tools, and create a single material with a single texture map. You can achieve a multi-texture effect with a custom ShaderMaterial. Have two texture inputs, and implement color mixing in the shader. Here an example of just about … Read more
The pointers which are allocated by using any of the CUDA Runtime’s device memory allocation functions e.g cudaMalloc or cudaMallocPitch are guaranteed to be 256 byte aligned, i.e. the address is a multiple of 256. Consider the following example: char *ptr1, *ptr2; int bytes = 1; cudaMalloc((void**)&ptr1,bytes); cudaMalloc((void**)&ptr2,bytes); Suppose the address returned in ptr1 is … Read more
As explained in ‘OpenGLES preloading textures in other thread‘ there are two separate steps: bitmap creation and bitmap upload. In most cases you should be fine by just doing the bitmap creation on a secondary thread — which is fairly easy. If you experience frame drops while uploading the textures, call texImage2D from a background … Read more
The easiest way to fix that is to make a 1×1 texture at creation time. var tex = gl.createTexture(); gl.bindTexture(gl.TEXTURE_2D, tex); gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 1, 1, 0, gl.RGBA, gl.UNSIGNED_BYTE, new Uint8Array([255, 0, 0, 255])); // red Then when the image loads you can replace the 1×1 pixel texture with the image. No flags needed and … Read more
Here’s a basic GLUT example (written on OS X, adapt as needed) that generates two checkerboard textures, loads a shader with two samplers and combines them by tinting each (one red, one blue) and blending. See if this works for you: #include <stdio.h> #include <stdlib.h> #include <GLUT/glut.h> #include <OpenGL/gl.h> #include <OpenGL/glu.h> #define kTextureDim 64 GLuint … Read more
usually rectangle texture is used for spheres texture (u,v) coordinates are used as angles for spherical coordinates. The result is that texels are bigger near equator and smaller near poles. At poles all the texels merge to single pixel. This is how to do it texturing spheres normal/bump mapping When you use these maps (color,normal,light,clouds): … Read more
I presume You added Your collada ( dae ) model like presented on the aframe docs: <a-scene> <a-assets> <a-asset-item id=”head” src=”https://stackoverflow.com/path/to/head.dae”></a-asset-item> </a-assets> <a-entity collada-model=”#head”></a-entity> </a-scene> To texture the model, You either need to: 1. Make a reference to the texture in the material of the entity. In <a-assets> make an img reference: <img id=”texture” src=”https://stackoverflow.com/questions/44451617/head.jpg”> … Read more
You can try attaching the texture to a framebuffer and then calling readPixels on the frame buffer. at init time // make a framebuffer fb = gl.createFramebuffer(); // make this the current frame buffer gl.bindFramebuffer(gl.FRAMEBUFFER, fb); // attach the texture to the framebuffer. gl.framebufferTexture2D( gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0); // check if you can read … Read more