#Opengl coords how to#
#Opengl coords software#
#Opengl coords code#

The problem is that I haven't seen the actual drawing code (or the entire code could work to), so i can't tell you how the triangle would actually behave with all that. Well, this is how I would do it, but there might be other ways to work this around. Once you have that, you will want to place one of the points of the triangle in that line, rotating the entire triangle to get that - I think that an easy way to do that would be by getting the angle of that line and rotating the entire triangle by that angle. If vertex coordinates(NDC) is inside clipping frustum it should be in -1, 1 interval for x,y and z. When I multiply vertex coordinates on modelview matrix and projection matrix I get homogenous coordinates, then if I divide them on w I get Normalized Device Coordinates (NDC). Your middle finger will point out at you. Hi I’m implementing my own OpenGL library. So if you take your right-hand, and point your thumb to the right and your index finger up. In the RHS, the x-axis is pointing right, y-axis is pointing up, and z-axis is pointing out of the. īut, basicaly, what you want is to find the line crossing the center of the triangle and the point were the mouse is. OpenGL is a right-handed coordinate system. OpenGL adopts the Right-Hand Coordinate System (RHS). I recomend that you become familiar at least with analitical geometry (how is that called in English?). 3D graphics card which supports OpenGL 3.0 and GLSL 1.3 or OpenGL ES 2.0. OpenGL Coordinate System Conventions Window origin conventions Direct3D upper-left origin OpenGL lower-left origin Pixel center conventions. Next, you will have to use some math to work it out. several coordinate grids precession circles star twinkling shooting stars. the OpenGL coordinates for the mouse - a good way to try this would be drawing a triangle were the mouse currently is, to make shure you have the right). Well, the first thing you will have to do is figure out were the mouse was suposed to be in your screen (i.e. Version 1.

#Opengl coords how to#

allows you to not only map the square coordinate system of OpenGL ES to the rectangular screen of an Android device, but also. 'Advanced Features' explains how to manipulate the texture matrix stack and how to use the q texture coordinate.

In other words, it doesnt offer any methods that allow you to quickly create or manipulate 3D objects. So, what I want to try and do is either switch the window coords to the 0,0 top left, or vice versa.

#Opengl coords software#

OpenGL is the software interface to graphics hardware.

Modern computers have dedicated GPU (Graphics Processing Unit) with its own memory to speed up graphics rendering. The window on the other hand uses 0,0 in the middle of the screen (annoying coords). OpenGL (Open Graphics Library) is a cross-platform, hardware-accelerated, language-independent, industrial standard API for producing 3D (including 2D) graphics. I didn't really understanded how are things working on your program, but I'm assuming you have a 2D view, with your triangle in the middle. OpenGL ES, short for OpenGL for Embedded Systems, is a subset of the API. The mouse coordinates return and x and y where 0,0 is the top left and y is inverted (standard coords). Well, I think that your problem is more about math then it is about OpenGL.