rendering graphics with opengl es

... CHAPTER OPENGL OPERATION Finally, command names, constants, and types are prefixed in the GL (by gl, GL , and GL, respectively in C) to reduce name clashes with other packages The prefixes are omitted ... array sizes (values per vertex) and data types present) For type the values BYTE, SHORT, INT, FLOAT, and DOUBLE indicate types byte, short, int, float, and double, respectively; and the values UNSIGNED ... occurs when the window system allocates a window for GL rendering The GL is designed to be run on a range of graphics platforms with varying graphics capabilities and performance To accommodate...

Ngày tải lên: 03/11/2012, 11:23

... Implementations Profiles and Versions OpenGL ES 1.0 in a Nutshell New Features in OpenGL ES 1.1 Extension Mechanism OpenGL ES Extension Pack Utility APIs Conventions Hello, OpenGL ES! CHAPTER OPENGL ES TRANSFORMATION ... computer graphics, but not necessarily in mobile devices The 3D graphics capabilities of mobile devices are exposed through two standardized application programming interfaces (APIs): OpenGL ES, typically ... plate.) 1.3.3 OPENGL ES OpenGL ES is a compact version of the well-known OpenGL graphics standard It is a low-level rendering API adapted for embedded systems The first version, OpenGL ES 1.0, aimed...

Ngày tải lên: 28/04/2014, 15:49

... Implementations Profiles and Versions OpenGL ES 1.0 in a Nutshell New Features in OpenGL ES 1.1 Extension Mechanism OpenGL ES Extension Pack Utility APIs Conventions Hello, OpenGL ES! CHAPTER OPENGL ES TRANSFORMATION ... Mobile 3D Graphics with OpenGL ES and M3G This page intentionally left blank Mobile 3D Graphics with OpenGL ES and M3G Kari Pulli Tomi Aarnio Ville Miettinen ... Storage 152 152 OPENGL ES AND EGL CHAPTER INTRODUCING OPENGL ES 157 7.1 Khronos Group and OpenGL ES 157 7.2 Design Principles 158 7.3 Resources 159 7.3.1 7.3.2 7.3.3 7.4 API Overview 7.4.1 7.4.2 7.4.3...

Ngày tải lên: 03/07/2014, 11:20

... computer graphics, but not necessarily in mobile devices The 3D graphics capabilities of mobile devices are exposed through two standardized application programming interfaces (APIs): OpenGL ES, typically ... of OpenGL ES and chaired the OpenGL ES working group from the beginning until OpenGL ES 2.0 Tom Olson was an active contributor from the beginning and became the next chair of the OpenGL ES working ... share the vision of omnipresent three-dimensional graphics on all mobile devices Compared to the contributions made through my research, the authors provide within these pages more than a small stepping...

Ngày tải lên: 03/07/2014, 11:20

... technology progresses at a much more modest rate, with the energy capacity of batteries increasing perhaps 10% per year at best In ten years’ time, processing power may well increase twenty times more ... of the devices incorporating graphics processors are high-end smart phones, but some feature phones with graphics hardware have also been released It is reasonable to expect that graphics acceleration ... Unlike the Japanese phones, it still had a monochrome screen with a mere 96 by 65 pixels of resolution—but it did incorporate all the essential 3D rendering features; internally, the graphics engine...

Ngày tải lên: 03/07/2014, 11:20

... plate.) 1.3.3 OPENGL ES OpenGL ES is a compact version of the well-known OpenGL graphics standard It is a low-level rendering API adapted for embedded systems The first version, OpenGL ES 1.0, aimed ... smart phones, modern games consoles, and beyond All OpenGL ES 2.x devices are expected to ship with ES 1.1 drivers Details of the 2.x standard are beyond the scope of this book GLSL ES is closely ... devices as well Later, OpenGL ES 1.1 included more features amenable to hardware acceleration, in line with the feature set of first-generation mobile 3D graphics chipsets The latest version, OpenGL...

Ngày tải lên: 03/07/2014, 11:20

... CHAPTER SECTION 2.2 MATRICES 31 2.1.3 HOMOGENEOUS COORDINATES Representing both points and direction vectors with three coordinates can be confusing Homogeneous coordinates are a useful tool to ... 3D GRAPHICS 28 CHAPTER eye coordinates Object coordinates clip coordinates w modelview matrix projection matrix near 2w 2w far height height viewport and depth range 0 width window coordinates ... correspond to the same 3D point We can also see that with normalized homogeneous coordinates—for which w is either or 0—taking a difference of two points creates a direction vector (w becomes...

Ngày tải lên: 03/07/2014, 11:20

... first moves the pivot to the origin, then applies an inverse rotation to align the desired direction of the scaling with the coordinate axes, performs the scaling, then rotates back and moves the ... coordinates or object coordinates must be transformed into the eye coordinate system, also known as camera coordinates, for rendering By definition, the camera in OpenGL ES and M3G lies at the origin of ... columns are y and z, respectively, expressed in XYZ coordinates T Now we can take an arbitrary point v = vx vy vz in eye coordinates xyz, and Mew produces the world coordinates XYZ for the same...

Ngày tải lên: 03/07/2014, 11:20

... define two planes, the near and far camera planes, and quantize the depths between the planes Any objects between these two planes are rendered, and any others ignored The depths of these objects ... therefore be expressed with matrices However, the conversion 50 LINEAR ALGEBRA FOR 3D GRAPHICS of homogeneous coordinates to 3D by dividing by the w component allows us to express the division, ... likelihood of z-fighting grows with the far/near ratio, with coarser display and depth buffer resolution, with increasing field of view and distance from the camera, and with increasing distance from...

Ngày tải lên: 03/07/2014, 11:20

... PRIMITIVES In this section we describe the rendering primitives of a 3D engine We begin with the geometric primitives such as points, lines, and triangles, and then continue to raster primitives using ... works only in the limit with a large enough closed mesh For smaller and irregular meshes, possibly with boundaries, there are usually 0.5–1.0 vertices 2 1 GL_LINES GL_TRIANGLES 5 GL_LINE_LOOP GL_TRIANGLE_STRIP ... PRIMITIVES The basic geometric primitives defined in OpenGL are points, lines, triangles, quads, and polygons However, in many hardware-accelerated 3D engines triangles are the only truly native rendering...

Ngày tải lên: 03/07/2014, 11:20

... image in one go However, if clipping the primitives introduces new vertices at image boundaries, and unless the colors and possibly other properties are interpolated using exactly the same algorithm ... LOW-LEVEL RENDERING 70 Real point light source energy is attenuated by the square of the distance from the light source However, OpenGL does not typically represent the true light energy, but a compressed ... sides 3.3 CULLING AND CLIPPING Not all primitives end up being visible For example, almost half of the triangles of typical scenes face away from the camera and may thus be discarded in the rendering...

Ngày tải lên: 03/07/2014, 11:20

... texture coordinates of the unit 3.4.2 INTERPOLATING GRADIENTS The simplest way to spread the values at vertices across triangles is to choose the values at one of the vertices and assign the ... for surfaces that are slanted with respect to the camera viewing direction Texture borders and linear interpolation The original OpenGL clamps texture coordinates to [0, 1], which gives problems ... linearly interpolates the associated values such as colors and texture coordinates to the pixels between the vertices We can express this using so-called barycentric coordinates If we take any...

Ngày tải lên: 03/07/2014, 11:20

... samples with their neighboring pixels, sometimes gaining better filtering at the cost of image sharpness 92 LOW-LEVEL RENDERING Other types of aliasing There are other sources of aliasing in 3D graphics ... approach, and the processing and memory requirements increase linearly by the number of samples per pixel Multisampling approximates supersampling with a more judicious use of resources At each pixel, ... not at their edges, edge antialiasing does not work, and the jaggies are fully visible Full-scene antialiasing Edge antialiasing only works at the edges of primitives, but jaggies can happen also...

Ngày tải lên: 03/07/2014, 11:20

... Compositor block handles the mixing of different types of content surfaces in the system, such as 3D rendering surfaces and native OS graphics Inside the GPU a command processor processes the commands ... alpha test to render them in two passes Multi-pass rendering The uses of blending are not limited to rendering translucent objects and compositing images on top of the background Multi-pass rendering ... components Rendering transparent objects OpenGL renders primitives in the same order as they are sent to the engine With depth buffering, one can use an arbitrary rendering order, as the closest surface...

Ngày tải lên: 03/07/2014, 11:20

... of describing predefined motions in computer graphics The term originates from cartoons, where the senior animator would first draw the most important “key” frames describing the main poses within ... between the mesh keyframes, we can just lerp between any two of them if the keyframes represent poses on a timeline Better yet, we can think of our keyframes as alternative shapes, or morph targets, ... classes of curves and splines used in computer graphics One type of spline commonly used in animation and modeling tools is an extension of Catmull-Rom splines called Kochanek-Bartels splines [KB84]...

Ngày tải lên: 03/07/2014, 11:20

... the mesh; see Section 3.4.1 for details IndexBuffers define the surface of the mesh by connecting vertices into triangles, as shown in Figure 5.2 OpenGL ES defines three ways to form triangles from ... ways, e.g., with polygons, lines, points, B´ zier patches, e NURBS, subdivision surfaces, implicit surfaces, or voxels, but in this chapter we concentrate on simple triangle meshes, as they are ... TRIANGLE MESHES A 3D object combines geometric primitives and rendering state into a self-contained visual entity that is easier to animate and interact with than the low-level bits and pieces are...

Ngày tải lên: 03/07/2014, 11:20

... conceptually based on OpenGL ES 1.0, it does not expose the low-level rendering context that it uses internally This design allows practical implementations to use later versions of OpenGL ES, proprietary ... coordinates are present, that triangle indices not point beyond vertex array boundaries, that a SkinnedMesh has all the necessary bones in place, and so on To compute the modelview matrix for a mesh, ... of renderables that are not ordinary triangle meshes, at least not from the user’s point of view Such renderables include spheres, cylinders, terrains, particles, impostors, skyboxes, and so on...

Ngày tải lên: 03/07/2014, 11:20

... rendering resolution—this is easiest done by scaling the viewport If the performance scales directly with the screen resolution, the bottleneck is in the pixel pipeline After this, further testing ... multiple times, or enabling unnecessary rendering states One potentially useful commercial tool for profiling your application is gDEBugger ES from Graphic Remedy It is an OpenGL ES debugger and ... profiler enables viewing context state variables (Figure 6.7), texture data and properties, performance counters, and OpenGL ES function call history It allows adding breakpoints on OpenGL ES commands,...

Ngày tải lên: 03/07/2014, 11:20

... combining application code with third-party middleware libraries that communicate directly with the underlying OpenGL ES or M3G layers If for some reason dynamic state queries are absolutely needed, ... therefore be costly State changes and under-the-hood synchronization may also happen when an application uses different APIs to access the same graphics resources For example, you may be tempted ... changes into “shaders” (we use the term here to indicate a collection of distinct pieces of the rendering state, corresponding roughly with the Appearance class of M3G), and to organize the rendering...

Ngày tải lên: 03/07/2014, 11:20

... versions of OpenGL ES and EGL specifications, reference manuals, and official header files The original OpenGL ES specification described the differences with respect to the desktop OpenGL (1.0 was ... Although this creates several “families” of OpenGL ES, it allows new major versions to start from a clean slate, and to come up with more elegant designs 7.3 RESOURCES Several free resources are available ... interested in using OpenGL ES Additional resources are available for Khronos members We list some of them below INTRODUCING OPENGL ES 160 7.3.1 DOCUMENTATION All of the official OpenGL ES documentation...

Ngày tải lên: 03/07/2014, 11:20