shithub: tinygl

ref: 18949a3f82797cdde959037b56781e1437b56176
dir: /SDL_Examples/gears.c/

View raw version
/* sdlGears.c */
/*
 * 3-D gear wheels by Brian Paul. This program is in the public domain.
 *
 * ported to libSDL/TinyGL by Gerald Franz (gfz@o2online.de)
 */

//#define PLAY_MUSIC

#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "../include/GL/gl.h"

#include "../include/zbuffer.h"
#define CHAD_API_IMPL
#define CHAD_MATH_IMPL
#include "include/3dMath.h"
#ifdef PLAY_MUSIC
#include "include/api_audio.h"
#else
typedef unsigned char uchar;
#endif
#include <SDL/SDL.h>

#ifndef M_PI
#define M_PI 3.14159265
#endif
int override_drawmodes = 0;
GLubyte stipplepattern[128] = {0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,

							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
							   0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55, 0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55};

/*
 * Draw a gear wheel.  You'll probably want to call this function when
 * building a display list since we do a lot of trig here.
 *
 * Input:  inner_radius - radius of hole at center
 *         outer_radius - radius at center of teeth
 *         width - width of gear
 *         teeth - number of teeth
 *         tooth_depth - depth of tooth
 */
static void gear(GLfloat inner_radius, GLfloat outer_radius, GLfloat width, GLint teeth, GLfloat tooth_depth) {
	GLint i;
	GLfloat r0, r1, r2;
	GLfloat angle, da;
	GLfloat u, v, len;

	r0 = inner_radius;
	r1 = outer_radius - tooth_depth / 2.0;
	r2 = outer_radius + tooth_depth / 2.0;

	da = 2.0 * M_PI / teeth / 4.0;

	glNormal3f(0.0, 0.0, 1.0);

	/* draw front face */
if(override_drawmodes == 1)
	glBegin(GL_LINES);
else if (override_drawmodes == 2)
	glBegin(GL_POINTS);
else
	{glBegin(GL_QUAD_STRIP);}
	for (i = 0; i <= teeth; i++) {
		angle = i * 2.0 * M_PI / teeth;
		glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
		glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
		glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
		glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5);
	}
	glEnd();

	/* draw front sides of teeth */
	if(override_drawmodes == 1)
		glBegin(GL_LINES);
	else if (override_drawmodes == 2)
		glBegin(GL_POINTS);
	else
		glBegin(GL_QUADS);
	da = 2.0 * M_PI / teeth / 4.0;
	for (i = 0; i < teeth; i++) {
		angle = i * 2.0 * M_PI / teeth;

		glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
		glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
		glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), width * 0.5);
		glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5);
	}
	glEnd();

	glNormal3f(0.0, 0.0, -1.0);

	/* draw back face */
	if(override_drawmodes == 1)
		glBegin(GL_LINES);
	else if (override_drawmodes == 2)
		glBegin(GL_POINTS);
	else
		glBegin(GL_QUAD_STRIP);
	for (i = 0; i <= teeth; i++) {
		angle = i * 2.0 * M_PI / teeth;
		glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
		glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
		glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5);
		glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
	}
	glEnd();

	/* draw back sides of teeth */
	if(override_drawmodes == 1)
		glBegin(GL_LINES);
	else if (override_drawmodes == 2)
		glBegin(GL_POINTS);
	else
		glBegin(GL_QUADS);
	da = 2.0 * M_PI / teeth / 4.0;
	for (i = 0; i < teeth; i++) {
		angle = i * 2.0 * M_PI / teeth;

		glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5);
		glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), -width * 0.5);
		glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
		glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
	}
	glEnd();

	/* draw outward faces of teeth */
	if(override_drawmodes == 1)
		glBegin(GL_LINES);
	else if (override_drawmodes == 2)
		glBegin(GL_POINTS);
	else
		glBegin(GL_QUAD_STRIP);
	for (i = 0; i < teeth; i++) {
		angle = i * 2.0 * M_PI / teeth;

		glVertex3f(r1 * cos(angle), r1 * sin(angle), width * 0.5);
		glVertex3f(r1 * cos(angle), r1 * sin(angle), -width * 0.5);
		u = r2 * cos(angle + da) - r1 * cos(angle);
		v = r2 * sin(angle + da) - r1 * sin(angle);
		len = sqrt(u * u + v * v);
		u /= len;
		v /= len;
		glNormal3f(v, -u, 0.0);
		glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), width * 0.5);
		glVertex3f(r2 * cos(angle + da), r2 * sin(angle + da), -width * 0.5);
		glNormal3f(cos(angle), sin(angle), 0.0);
		glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), width * 0.5);
		glVertex3f(r2 * cos(angle + 2 * da), r2 * sin(angle + 2 * da), -width * 0.5);
		u = r1 * cos(angle + 3 * da) - r2 * cos(angle + 2 * da);
		v = r1 * sin(angle + 3 * da) - r2 * sin(angle + 2 * da);
		glNormal3f(v, -u, 0.0);
		glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), width * 0.5);
		glVertex3f(r1 * cos(angle + 3 * da), r1 * sin(angle + 3 * da), -width * 0.5);
		glNormal3f(cos(angle), sin(angle), 0.0);
	}

	glVertex3f(r1 * cos(0), r1 * sin(0), width * 0.5);
	glVertex3f(r1 * cos(0), r1 * sin(0), -width * 0.5);

	glEnd();


	/* draw inside radius cylinder */
	if(override_drawmodes == 1)
		glBegin(GL_LINES);
	else if (override_drawmodes == 2)
		glBegin(GL_POINTS);
	else
		glBegin(GL_QUAD_STRIP);
	for (i = 0; i <= teeth; i++) {
		angle = i * 2.0 * M_PI / teeth;
		glNormal3f(-cos(angle), -sin(angle), 0.0);
		glVertex3f(r0 * cos(angle), r0 * sin(angle), -width * 0.5);
		glVertex3f(r0 * cos(angle), r0 * sin(angle), width * 0.5);
	}
	glEnd();
}

static GLfloat view_rotx = 20.0, view_roty = 30.0;
static GLint gear1, gear2, gear3;
static GLfloat angle = 0.0;

void draw() {
	angle += 2.0;
	glPushMatrix();
	glRotatef(view_rotx, 1.0, 0.0, 0.0);
	glRotatef(view_roty, 0.0, 1.0, 0.0);
	// glRotatef( view_rotz, 0.0, 0.0, 1.0 );

	glPushMatrix();
	glTranslatef(-3.0, -2.0, 0.0);
	glRotatef(angle, 0.0, 0.0, 1.0);
	glCallList(gear1);
	glPopMatrix();

	glPushMatrix();
	glTranslatef(3.1, -2.0, 0.0);
	glRotatef(-2.0 * angle - 9.0, 0.0, 0.0, 1.0);
	glCallList(gear2);
	glPopMatrix();

	glPushMatrix();
	glTranslatef(-3.1, 4.2, 0.0);
	glRotatef(-2.0 * angle - 25.0, 0.0, 0.0, 1.0);
	glCallList(gear3);
	glPopMatrix();

	glPopMatrix();
}

void initScene() {
	// static GLfloat pos[4] = {0.408248290463863, 0.408248290463863, 0.816496580927726, 0.0 }; //Light at infinity.
	static GLfloat pos[4] = {5, 5, 10, 0.0}; // Light at infinity.

	static GLfloat red[4] = {1.0, 0.0, 0.0, 0.0};
	static GLfloat green[4] = {0.0, 1.0, 0.0, 0.0};
	static GLfloat blue[4] = {0.0, 0.0, 1.0, 0.0};
	static GLfloat white[4] = {1.0, 1.0, 1.0, 0.0};

	glLightfv(GL_LIGHT0, GL_POSITION, pos);
	glLightfv(GL_LIGHT0, GL_DIFFUSE, white);
	// glLightfv( GL_LIGHT0, GL_AMBIENT, white);
	// glLightfv( GL_LIGHT0, GL_SPECULAR, white);
	glEnable(GL_CULL_FACE);
	
	glEnable(GL_LIGHT0);
	//glEnable(GL_DEPTH_TEST);
	

	glEnable(GL_POLYGON_STIPPLE);
//	glDisable(GL_POLYGON_STIPPLE);
	glPolygonStipple(stipplepattern);

	glTextSize(GL_TEXT_SIZE24x24);
	/* make the gears */
	gear1 = glGenLists(1);
	glNewList(gear1, GL_COMPILE);
	glMaterialfv(GL_FRONT, GL_DIFFUSE, blue);
	glColor3fv(blue);
	gear(1.0, 4.0, 1.0, 20, 0.7); // The largest gear.
	glEndList();

	gear2 = glGenLists(1);
	glNewList(gear2, GL_COMPILE);
	glMaterialfv(GL_FRONT, GL_DIFFUSE, red);
	glColor3fv(red);
	gear(0.5, 2.0, 2.0, 10, 0.7); // The small gear with the smaller hole, to the right.
	glEndList();

	gear3 = glGenLists(1);
	glNewList(gear3, GL_COMPILE);
	glMaterialfv(GL_FRONT, GL_DIFFUSE, green);
	glColor3fv(green);
	gear(1.3, 2.0, 0.5, 10, 0.7); // The small gear above with the large hole.
	glEndList();
	// glEnable( GL_NORMALIZE );
}

static inline GLfloat TEST_fastInvSqrt(float x){
	GLint i; GLfloat y;
	memcpy(&i, &x, 4);
	i = 0x5f3759df - (i>>1);
	//y = (union{GLint l; GLfloat f; }){i}.f;
	memcpy(&y, &i, 4);
	return y * (1.5F - 0.5F * x * y * y);
}

int main(int argc, char** argv) {
	// initialize SDL video:
	int winSizeX = 640;
	int winSizeY = 480;
	unsigned int fps = 0;
	unsigned int flat = 0;
	unsigned int setenspec = 1;
	unsigned int dotext = 1;
	unsigned int blending = 0;
	char needsRGBAFix = 0;
	if (argc > 1) {
		char* larg = "";
		for (int i = 1; i < argc; i++) {
			if (!strcmp(larg, "-w"))
				winSizeX = atoi(argv[i]);
			if (!strcmp(larg, "-h"))
				winSizeY = atoi(argv[i]);
			if (!strcmp(larg, "-fps"))
				fps = strtoull(argv[i], 0, 10);
			if (!strcmp(argv[i],"-flat"))
				flat = 1;
			if (!strcmp(argv[i],"-smooth"))
				flat = 0;
			if (!strcmp(argv[i],"-blend"))
				blending = 1;
			if (!strcmp(argv[i],"-nospecular"))
				setenspec = 0;
			if (!strcmp(argv[i],"-lines"))
				override_drawmodes = 1;
			if (!strcmp(argv[i],"-points"))
				override_drawmodes = 2;
			if (!strcmp(argv[i],"-notext"))
				dotext = 0;
			larg = argv[i];
		}
	}
#ifdef PLAY_MUSIC
	if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) < 0) {
#else
	if (SDL_Init(SDL_INIT_VIDEO) < 0) {
#endif
		fprintf(stderr, "ERROR: cannot initialize SDL video.\n");
		return 1;
	}
#ifdef PLAY_MUSIC
	ainit(0);
#endif
	SDL_Surface* screen = NULL;
	if ((screen = SDL_SetVideoMode(winSizeX, winSizeY, TGL_FEATURE_RENDER_BITS, SDL_SWSURFACE)) == 0) {
		fprintf(stderr, "ERROR: Video mode set failed.\n");
		return 1;
	}
	printf("\nRMASK IS %u", screen->format->Rmask);
	printf("\nGMASK IS %u", screen->format->Gmask);
	printf("\nBMASK IS %u", screen->format->Bmask);
	printf("\nAMASK IS %u", screen->format->Amask);
#if TGL_FEATURE_RENDER_BITS == 32
	if (screen->format->Rmask != 0x00FF0000 || screen->format->Gmask != 0x0000FF00 || screen->format->Bmask != 0x000000FF) {
		needsRGBAFix = 1;
		printf("\nYour screen is using an RGBA output different than this library expects.");
		printf("\nYou should consider using the 16 bit version for optimal performance");
	}
#endif
	printf("\nRSHIFT IS %u", screen->format->Rshift);
	printf("\nGSHIFT IS %u", screen->format->Gshift);
	printf("\nBSHIFT IS %u", screen->format->Bshift);
	printf("\nASHIFT IS %u\n", screen->format->Ashift);
	fflush(stdout);
	
#ifdef PLAY_MUSIC
	track* myTrack = NULL;
	myTrack = lmus("WWGW.mp3");
	mplay(myTrack, -1, 1000);
#endif
	SDL_ShowCursor(SDL_DISABLE);
	SDL_WM_SetCaption(argv[0], 0);

	// initialize TinyGL:
	// unsigned int pitch;
	int mode;
	switch (screen->format->BitsPerPixel) {
	case 8:
		fprintf(stderr, "ERROR: Palettes are currently not supported.\n");
		fprintf(stderr, "\nUnsupported by maintainer!!!");
		return 1;
	case 16:
		// pitch = screen->pitch;
		// fprintf(stderr,"\nUnsupported by maintainer!!!");
		mode = ZB_MODE_5R6G5B;
		// return 1;
		break;
	case 24:
		// pitch = ( screen->pitch * 2 ) / 3;
		fprintf(stderr, "\nUnsupported by maintainer!!!");
		mode = ZB_MODE_RGB24;
		return 1;
		break;
	case 32:
		// pitch = screen->pitch / 2;
		mode = ZB_MODE_RGBA;
		break;
	default:
		return 1;
		break;
	}
	ZBuffer* frameBuffer = ZB_open(winSizeX, winSizeY, mode, 0);
	if(!frameBuffer){printf("\nZB_open failed!");exit(1);}
	glInit(frameBuffer);

	//Print version info
	printf("\nVersion string:\n%s",glGetString(GL_VERSION));
	printf("\nVendor string:\n%s",glGetString(GL_VENDOR));
	printf("\nRenderer string:\n%s",glGetString(GL_RENDERER));
	printf("\nExtensions string:\n%s",glGetString(GL_EXTENSIONS));
	printf("\nLicense string:\n%s",glGetString(GL_LICENSE));
	// initialize GL:
	glClearColor(0.0, 0.0, 0.0, 0.0);
	glViewport(0, 0, winSizeX, winSizeY);
if(flat)	glShadeModel(GL_FLAT); else glShadeModel(GL_SMOOTH);
//TESTING BLENDING...
	//glDisable(GL_DEPTH_TEST);


	//glDisable( GL_LIGHTING );
	glEnable(GL_LIGHTING);
	glBlendFunc(GL_ONE_MINUS_SRC_COLOR, GL_ZERO);
	glBlendEquation(GL_FUNC_ADD);
	if(blending){
		glDisable(GL_DEPTH_TEST);
		glEnable(GL_BLEND);
		glDepthMask(GL_FALSE);
		glBlendFunc(GL_SRC_COLOR, GL_DST_COLOR);
		glBlendEquation(GL_FUNC_ADD);
	}else{
		glEnable(GL_DEPTH_TEST);
		glDisable(GL_BLEND);
		glDepthMask(GL_TRUE);
	}
	GLfloat h = (GLfloat)winSizeY / (GLfloat)winSizeX;
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glFrustum(-1.0, 1.0, -h, h, 5.0, 60.0);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glTranslatef(0.0, 0.0, -45.0);

	initScene();
	if(setenspec) glSetEnableSpecular(GL_TRUE); else glSetEnableSpecular(GL_FALSE);
	// variables for timing:
	unsigned int frames = 0;
	unsigned int tNow = SDL_GetTicks();
	unsigned int tLastFps = tNow;

	// main loop:
	int isRunning = 1;
	//float test = 0;
	while (isRunning) {
		++frames;
		tNow = SDL_GetTicks();
	//	test = TEST_fastInvSqrt(tNow);
	//	printf("\n%f",test);
		// do event handling:
		SDL_Event evt;
		while (SDL_PollEvent(&evt))
			switch (evt.type) {
			case SDL_KEYDOWN:
				switch (evt.key.keysym.sym) {
				case SDLK_UP:
					view_rotx += 5.0;
					break;
				case SDLK_DOWN:
					view_rotx -= 5.0;
					break;
				case SDLK_LEFT:
					view_roty += 5.0;
					break;
				case SDLK_RIGHT:
					view_roty -= 5.0;
					break;
				case SDLK_ESCAPE:
				case SDLK_q:
					isRunning = 0;
				default:
					break;
				}
				break;
			case SDL_QUIT:
				isRunning = 0;
				break;
			}

		// draw scene:
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
		draw();
		if(dotext){
			glDrawText((unsigned char*)"RED text", 0, 0, 0xFF0000);

			glDrawText((unsigned char*)"GREEN text", 0, 24, 0x00FF00);

			glDrawText((unsigned char*)"BLUE text", 0, 48, 0xFF);
		}
		// swap buffers:
		if (SDL_MUSTLOCK(screen) && (SDL_LockSurface(screen) < 0)) {
			fprintf(stderr, "SDL ERROR: Can't lock screen: %s\n", SDL_GetError());
			return 1;
		}
		// Quickly convert all pixels to the correct format
#if TGL_FEATURE_RENDER_BITS == 32
		// for testing!
		if (needsRGBAFix)
			for (int i = 0; i < frameBuffer->xsize * frameBuffer->ysize; i++) {
#define DATONE (frameBuffer->pbuf[i])
				DATONE = ((DATONE & 0x00FF0000)) << screen->format->Rshift | ((DATONE & 0x0000FF00) >> 8) << screen->format->Gshift |
						 ((DATONE & 0x000000FF) >> 16) << screen->format->Bshift;
			}
#endif
		ZB_copyFrameBuffer(frameBuffer, screen->pixels, screen->pitch);
		if (SDL_MUSTLOCK(screen))
			SDL_UnlockSurface(screen);
		SDL_Flip(screen);
		if (fps > 0)
			if ((1000 / fps) > (SDL_GetTicks() - tNow)) {
				SDL_Delay((1000 / fps) - (SDL_GetTicks() - tNow)); // Yay stable framerate!
			}
		// check for error conditions:
		char* sdl_error = SDL_GetError();
		if (sdl_error[0] != '\0') {
			fprintf(stderr, "SDL ERROR: \"%s\"\n", sdl_error);
			SDL_ClearError();
		}
		// update fps:
		if (tNow >= tLastFps + 5000) {
			printf("%i frames in %f secs, %f frames per second.\n", frames, (float)(tNow - tLastFps) * 0.001f,
				   (float)frames * 1000.0f / (float)(tNow - tLastFps));
			tLastFps = tNow;
			frames = 0;
		}
	}
	printf("%i frames in %f secs, %f frames per second.\n", frames, (float)(tNow - tLastFps) * 0.001f, (float)frames * 1000.0f / (float)(tNow - tLastFps));
	// cleanup:
	//glDeleteList(gear1);
	//glDeleteList(gear2);
	//glDeleteList(gear3);
	ZB_close(frameBuffer);
	glClose();
	if (SDL_WasInit(SDL_INIT_VIDEO))
		SDL_QuitSubSystem(SDL_INIT_VIDEO);
#ifdef PLAY_MUSIC
	mhalt();
	Mix_FreeMusic(myTrack);
	acleanup();
#endif
	SDL_Quit();
	return 0;
}