Chameleon game engine

transcript

Chameleon3D game engine

Tuesday, January 18, 2011

Overview

•OpenGL 2.0+ (desktop), ES 1.1, 2.0 (mobile)

•DirectX support (windows)

•C based•Platform independent•Lightweight, easy syntax•Complex API•Easily scalable•Tons of built-in features

OpenGL ES

•OpenGL API subset•Designed for embedded devices•Perfect for 3D on the iPhone/iPod touch & iPad•Also perfect for Android•Hardware accelerated rendering on the GPU•CPU should do almost no work•...but it’s pretty complicated!•...quite hard to find the perfect optimizations•...inexperienced programmers will make games 50x slower

•Renderer abstraction•Works on iOS, Android, Mac, Linux, Windows•Advanced 2D functions (arc, shape, bezier, catmull etc.)

•Eye-candy effects (blend, glow, diffuse, tint etc.)

•Fast image loading/compression (to 2 bits per pixel)

•Lights (ambient, point, spot) and materials•Shadows, reflections•Shape primitives (cube, sphere, cylinder, torus etc.)

Chameleonfeatures

Featuresfeatures (continued)

•3D model loading (geometry, textures)

•Skybox, sphere map•Particle system emitters (fire, explosions etc.)

•Imposters, billboard nodes (vegetation, trees etc.)

•Camera (yaw, pitch, roll: position, rotation)

•Camera controllers (arcball, fps, rpg, etc.)

•Offscreen canvas•...plus, many others•...optimized for each platform

Architecture

•Window engine context setup

‣Position on screen (or parent view) - x, y, width, height‣Fullscreen (or not)‣Display refresh rate, bits per pixel‣Input and mouse (touch) position, state, gestures

•Renderer hardware accelerated

‣Built-in capabilities abstraction layer‣Around 20 extremely low level drawing functions‣Entire engine relies only on them‣Easily scalable on any hardware

Architecture

•Canvas drawing layer

‣Coordinate system functions (translate, rotate, scale, transform)‣Styles (fill, stroke, tint, blend, alpha, add, mask etc.)‣Pixels, points, lines, n-sided polygons (rectangle, ellipse etc.)‣Convex/ concave shapes, bezier curves, cubic hermite splines‣Images, sprites, animations‣3D primitives (cube, sphere, cylinder, capsule, torus etc.)‣Lights, shadows, materials, reflections setup

+ Core extensions the user friendly high-level interface

+ Utilities the must-have game API (resource locator, image loader, files, sound, xml etc.)

Snippets

•CImage *img = loadImage("test.jpg", kSmooth)•image(img, 0, 0, img->width, img->height);

•CColor color;•getImagePixel(img, &color, 100, 100);•setImagePixel(img, initColor(255, 0, 0, 128), 100, 100);

•CModel *model = loadModel("fighter.3ds");•geometryRotation(model->geometry, PI, -HALF_PI, 0);•drawModel(model);

•pointLight(0, initVector3(5, -2, 0), initAmbient(192, 192, 128), ! ! ! initDiffuse(192, 192, 192),! ! ! initSpecular(255, 128, 64));

•materialSpecular(255, 255, 255);•materialShininess(128);

•translate(5, 2, -6);•rotate(radians(60), 1, 1, 0);•scale(2, 3, 1);

ExampleLenna

float frameCount;

CArcball *arcb;CColor *col;CImage *img;

#define step 2

- (void)setup {! defaults();! optimize3D();! noPointSmooth();! createPrimitives();!! perspective(45, (float)e.width / e.height, 1, 100);!! arcb = initArcball(e.width / 2, e.height / 2, e.height);! col = initColor(0, 0, 0, 0);! img = loadImage("lenna320.jpg", kSmooth);}

- (void)draw {! clear();! origin();!! translateZ(-4);!! rotateScene(arcb);!! noFill();! whiteStroke();! cube(0, 0, 0, img->width, img->height, img->width);! ellipse(0, 0, e.width, e.width);!! beginPixels();! for (float i = 0; i < img->width; i += step) {! ! for (float j = 0; j < img->height; j += step) {! ! ! getImagePixel(img, col, i, j);! ! ! float br = brightness(col->r, col->g, col->b);! ! ! pixelColor(i - img->width / 2, ! ! ! ! ! j - img->height / 2, ! ! ! ! ! br * fastsin(frameCount) / 2,! ! ! ! ! col->r, col->g, col->b, 255);! ! }! }! endPixels();

! frameCount += .1;!! gl.present(self.view);}

ExampleLenna

float frameCount;

CArcball *arcb;CColor *col;CImage *img;

#define step 2

- (void)setup {! defaults();! optimize3D();! noPointSmooth();! createPrimitives();!! perspective(45, (float)e.width / e.height, 1, 100);!! arcb = initArcball(e.width / 2, e.height / 2, e.height);! col = initColor(0, 0, 0, 0);! img = loadImage("lenna320.jpg", kSmooth);}

- (void)draw {! clear();! origin();!! translateZ(-4);!! rotateScene(arcb);!! noFill();! whiteStroke();! cube(0, 0, 0, img->width, img->height, img->width);! ellipse(0, 0, e.width, e.width);!! beginPixels();! for (float i = 0; i < img->width; i += step) {! ! for (float j = 0; j < img->height; j += step) {! ! ! getImagePixel(img, col, i, j);! ! ! float br = brightness(col->r, col->g, col->b);! ! ! pixelColor(i - img->width / 2, ! ! ! ! ! j - img->height / 2, ! ! ! ! ! br * fastsin(frameCount) / 2,! ! ! ! ! col->r, col->g, col->b, 255);! ! }! }! endPixels();

! frameCount += .1;!! gl.present(self.view);}

Live coding/deployment!ghter aircraft - model loading, environment, lighting, shadows

Chameleon game engine

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