texture-mapping

I have a GL_QUAD_STRIP that I am texture mapping. The quad strip folds back on itself to form a UV sphere. Essentially, the quad strip is not generally made of rectangles--instead, trapezoids. I am getting texture distortion issues. The texture coordinates are correct (for example, they line up nicely where they should). The issue is on the trapezoidal faces themselves. I would expect texels towards the larger end of a trapezoidal face to subtend larger area, yet the face seems broken into two triangles. It looks similar to affine texture mapping (but I don't think it is; it still seems

Can you explain me, why hardware acceleration required for a long time textures be power of two? For PCs, since GeForce 6 we achieved npot textures with no-mips and simplified filtering. OpenGL ES 2.0 also supports npot textures without mipmaps and etc. What is the hardware restriction for this? Just simplified arithmetics? I imagine it has to do with being able to use bitwise shift-left operations, rather than multiplication to convert an (x, y) coordinate to a memory offset from the start of the texture. So yes, simplified arithmetics, from a processor point of view. I'm guessing that it was

I want to plot a surface with a texture map on it, but the conditions are not the "ideal" ones. first lets explain what I have. I have a set of points (~7000) that are image coordinates, in a grid. This points do NOT define perfect squares. IT IS NOT A MESHGRID . For the sake of the question, lets assume that we have 9 points. Lets ilustrate what we have with an image: X=[310,270,330,430,410,400,480,500,520] Y=[300,400,500,300,400,500,300,400,500] Lets say we can get the "structure" of the grid, so size1=3; size2=3; points=zeros(size1,size2,2) X=[310,270,330; 430,410,400; 480,500,520] Y=[300

I have seams between horizontal faces of the cube when use texture atlas in three.js. This is demo: http://jsfiddle.net/rnix/gtxcj3qh/7/ or http://jsfiddle.net/gtxcj3qh/8/ (from comments) Screenshot of the problem: Here I use repeat and offset: var materials = []; var t = []; var imgData = document.getElementById("texture_atlas").src; for ( var i = 0; i < 6; i ++ ) { t[i] = THREE.ImageUtils.loadTexture( imgData ); //2048x256 t[i].repeat.x = 1 / 8; t[i].offset.x = i / 8; //t[i].magFilter = THREE.NearestFilter; t[i].minFilter = THREE.NearestFilter; t[i].generateMipmaps = false; materials.push(

I successfully applied a texture to a cube geometry with this: var geometry = new THREE.CubeGeometry(10, 10, 10); var meshMaterial = new THREE.MeshPhongMaterial({ transparent: false, map: THREE.ImageUtils.loadTexture('/app/images/wood.jpg') }); meshMaterial.side = THREE.DoubleSide; var mesh = new THREE.Mesh(geometry, meshMaterial); With this I get a nice textured cube like this: Now I want to apply the same texture (512x512 jpg image) to a custom model I'm loading from an STL and this is what I get (in this case a pyramid): This is the code: loader.load(jsonParam.url, function (geometry) { var