axmol/tests/cpp-tests/Classes/ChipmunkTestBed/demo/Player.c

/* Copyright (c) 2007 Scott Lembcke
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "chipmunk/chipmunk_private.h"
#include "ChipmunkDemo.h"

#define PLAYER_VELOCITY 500.0

#define PLAYER_GROUND_ACCEL_TIME 0.1
#define PLAYER_GROUND_ACCEL      (PLAYER_VELOCITY / PLAYER_GROUND_ACCEL_TIME)

#define PLAYER_AIR_ACCEL_TIME 0.25
#define PLAYER_AIR_ACCEL      (PLAYER_VELOCITY / PLAYER_AIR_ACCEL_TIME)

#define JUMP_HEIGHT       50.0
#define JUMP_BOOST_HEIGHT 55.0
#define FALL_VELOCITY     900.0
#define GRAVITY           2000.0


static cpBody* playerBody = NULL;
static cpShape* playerShape = NULL;

static cpFloat remainingBoost = 0;
static cpBool grounded = cpFalse;
static cpBool lastJumpState = cpFalse;

static void SelectPlayerGroundNormal(cpBody* body, cpArbiter* arb, cpVect* groundNormal) {
	cpVect n = cpvneg(cpArbiterGetNormal(arb));

	if (n.y > groundNormal->y) {
		(*groundNormal) = n;
	}
}

static void playerUpdateVelocity(cpBody* body, cpVect gravity, cpFloat damping, cpFloat dt) {
	int jumpState = (ChipmunkDemoKeyboard.y > 0.0f);

	// Grab the grounding normal from last frame
	cpVect groundNormal = cpvzero;
	cpBodyEachArbiter(playerBody, (cpBodyArbiterIteratorFunc)SelectPlayerGroundNormal, &groundNormal);

	grounded = (groundNormal.y > 0.0);
	if (groundNormal.y < 0.0f)
		remainingBoost = 0.0f;

	// Do a normal-ish update
	cpBool boost = (jumpState && remainingBoost > 0.0f);
	cpVect g = (boost ? cpvzero : gravity);
	cpBodyUpdateVelocity(body, g, damping, dt);

	// Target horizontal speed for air/ground control
	cpFloat target_vx = PLAYER_VELOCITY * ChipmunkDemoKeyboard.x;


	// Update the surface velocity and friction
	// Note that the "feet" move in the opposite direction of the player.
	cpVect surface_v = cpv(-target_vx, 0.0);
	playerShape->surfaceV = surface_v;
	playerShape->u = (grounded ? PLAYER_GROUND_ACCEL / GRAVITY : 0.0);

	// Apply air control if not grounded
	if (!grounded) {
		// Smoothly accelerate the velocity
		playerBody->v.x = cpflerpconst(playerBody->v.x, target_vx, PLAYER_AIR_ACCEL * dt);
	}

	body->v.y = cpfclamp(body->v.y, -FALL_VELOCITY, INFINITY);
}

static void update(cpSpace* space, double dt) {
	int jumpState = (ChipmunkDemoKeyboard.y > 0.0f);

	// If the jump key was just pressed this frame, jump!
	if (jumpState && !lastJumpState && grounded) {
		cpFloat jump_v = cpfsqrt(2.0 * JUMP_HEIGHT * GRAVITY);
		playerBody->v = cpvadd(playerBody->v, cpv(0.0, jump_v));

		remainingBoost = JUMP_BOOST_HEIGHT / jump_v;
	}

	// Step the space
	cpSpaceStep(space, dt);

	remainingBoost -= dt;
	lastJumpState = jumpState;
}

static cpSpace* init(void) {
	cpSpace* space = cpSpaceNew();
	space->iterations = 10;
	space->gravity = cpv(0, -GRAVITY);
	//	space->sleepTimeThreshold = 1000;

	cpBody* body, * staticBody = cpSpaceGetStaticBody(space);
	cpShape* shape;

	// Create segments around the edge of the screen.
	shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320, -240), cpv(-320, 240), 0.0f));
	shape->e = 1.0f;
	shape->u = 1.0f;
	cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);

	shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(320, -240), cpv(320, 240), 0.0f));
	shape->e = 1.0f;
	shape->u = 1.0f;
	cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);

	shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320, -240), cpv(320, -240), 0.0f));
	shape->e = 1.0f;
	shape->u = 1.0f;
	cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);

	shape = cpSpaceAddShape(space, cpSegmentShapeNew(staticBody, cpv(-320, 240), cpv(320, 240), 0.0f));
	shape->e = 1.0f;
	shape->u = 1.0f;
	cpShapeSetFilter(shape, NOT_GRABBABLE_FILTER);

	// Set up the player
	body = cpSpaceAddBody(space, cpBodyNew(1.0f, INFINITY));
	body->p = cpv(0, -200);
	body->velocity_func = playerUpdateVelocity;
	playerBody = body;

	shape = cpSpaceAddShape(space, cpBoxShapeNew2(body, cpBBNew(-15.0, -27.5, 15.0, 27.5), 1.0));
	//	shape = cpSpaceAddShape(space, cpSegmentShapeNew(playerBody, cpvzero, cpv(0, radius), radius));
	shape->e = 0.0f;
	shape->u = 0.0f;
	shape->type = 1;
	playerShape = shape;

	// Add some boxes to jump on
	for (int i = 0; i < 6; i++) {
		for (int j = 0; j < 3; j++) {
			body = cpSpaceAddBody(space, cpBodyNew(4.0f, INFINITY));
			body->p = cpv(100 + j * 60, -200 + i * 60);

			shape = cpSpaceAddShape(space, cpBoxShapeNew(body, 50, 50, 0.0));
			shape->e = 0.0f;
			shape->u = 0.7f;
		}
	}

	return space;
}

static void destroy(cpSpace* space) {
	ChipmunkDemoFreeSpaceChildren(space);
	cpSpaceFree(space);
}

ChipmunkDemo PlatformerPlayer = {
	"Platformer Player Controls",
	1.0 / 180.0,
	init,
	update,
	ChipmunkDemoDefaultDrawImpl,
	destroy,
};