Initial clone in from local subversion server

2011-05-26 02:24:33 +00:00
commit ccca81e04e
87 changed files with 20290 additions and 0 deletions
--- a/demo/frictionball/cpp/demo.cpp
+++ b/demo/frictionball/cpp/demo.cpp
@@ -0,0 +1,92 @@
+/*
+ * This demo expands on the bouncingball demo to show how you can integrate simple physics to create a
+ * more realistic bouncing effect, and bring the ball to a halt
+ */
+
+#include <libgame/libgame.h>
+
+int main(int argc, char *argv[])
+{
+	Display2D display = Display2D();
+	Game &myGame = Game::NewSingleton();
+	Animation *anim = NULL;
+	Actor ball;
+	SpriteStrip *strip = NULL;
+	float gravity = 0.1;
+	unsigned int lastTimer = 0;
+
+	Vector actorPos;
+	Vector actorVel;
+
+	myGame.initSDL();
+	myGame.initVideo(640, 480, 32, SDL_HWSURFACE|SDL_DOUBLEBUF);
+	display.initVideo((Vector){0,0,0}, 640, 480, 32, SDL_HWSURFACE);
+	display.setActive(1);
+	myGame.windows.push_back(&display);
+
+	strip = myGame.newSpriteStrip("ball");
+	strip->loadFromFile("ball.png", 32, 32, (Vector){0,0,0});
+	anim = myGame.newAnimation("ball");
+	anim->setStrip(strip, 0, 0, (Vector){0,0,0});
+	ball.addAnimation(anim, STATE_DEFAULT);
+	ball.setState(STATE_MOVERIGHT | STATE_MOVEUP);
+	ball.setPosition((Vector){320,240,0});
+	ball.setVelocity((Vector){-1, 0, 0});
+
+	display.addActor(&ball, LAYER_SPRITE1);
+
+	lastTimer = SDL_GetTicks();
+	myGame.lockFPS(60);
+
+	while ( 1 ) {
+	    actorPos = ball.getPosition();
+	    actorVel = ball.getVelocity();
+	    /* this is what does the bounce */
+	    if ( actorPos.y > (480 - ball.nextFrame()->h) ) {
+		// if the velocity is low enough, then we just stop the ball so that it will roll
+		// smoothly along the floor of the window
+		if ( actorVel.y < .01 && actorVel.y > -.01 ) {
+		    actorVel.y = 0;
+		} else {
+		    // if the velocity is still significant, then we reverse it to create the bounce
+		    // but since real balls don't bounce quite as high as they did initially, when dropped
+		    // so we do a primitive modification of the velocity to inroduce something similar to
+		    // friction physics (see the "physics" demos for ACTUAL physics)
+
+		    // The friction numbers here are arbitrary, and were used because they made sense in the
+		    // demo, you can change the friction for some pretty different effects.
+		    actorVel.y = -(actorVel.y) - 1;
+		    // this is friction applied to the X axis to stop the ball's movement eventually
+		    if ( actorVel.x < .01 && actorVel.x > -.01 ) {
+			actorVel.x = 0;
+		    } else {
+			if ( actorVel.x > 0  ) {
+			    actorVel.x -= .1;
+			} else {
+			    actorVel.x += .1;
+			}
+		    }
+		}
+		actorPos.y = (480 - ball.nextFrame()->h);
+		ball.setPosition(actorPos);
+	    }
+	    if ( ((actorPos.x + ball.nextFrame()->w) >= 640) || actorPos.x < 0 ) {
+		actorVel.x = -(actorVel.x);
+	    }
+	    // -- end of bouncing
+	    if ( actorPos.x >= 640 ) {
+		break;
+	    }
+	    if ( (SDL_GetTicks() - lastTimer) >= (1000/30) ) {
+		actorVel.y -= gravity;
+		ball.setVelocity(actorVel);
+		lastTimer = SDL_GetTicks();
+	    }
+	    myGame.update();
+	    if ( myGame.keyHeldDown(SDLK_ESCAPE) ) {
+		break;
+	    }
+	    myGame.finishFrame();
+	}
+	return 0;
+}