view test/testdyngl.c @ 2661:d38309be5178 gsoc2008_audio_resampling

The windowed sinc filter generation code seems to be working fine. The FIR filtering code is also now working reasonably well. Occasionally the FIR filter will pop, but setting the normalization factor lower seems to help this. I suspect the problem is in the fixed point multiply/add. I also have a hunch the zero stuffing/sample discarding code is not correct, and I'll look at that soon to get it sorted out.
author Aaron Wishnick <schnarf@gmail.com>
date Wed, 02 Jul 2008 08:04:50 +0000
parents 7b53a8401195
children e27bdcc80744
line wrap: on
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/*
 * Small SDL example to demonstrate dynamically loading 
 * OpenGL lib and functions
 *
 * (FYI it was supposed to look like snow in the wind or something...)
 *
 * Compile with :
 * gcc testdyngl.c `sdl-config --libs --cflags` -o testdyngl -DHAVE_OPENGL
 *
 * You can specify a different OpenGL lib on the command line, i.e. :
 * ./testdyngl  /usr/X11R6/lib/libGL.so.1.2
 * or
 * ./testdyngl  /usr/lib/libGL.so.1.0.4496
 *
 */

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

#include "SDL.h"

#ifdef __MACOS__
#define HAVE_OPENGL
#endif

#ifdef HAVE_OPENGL

#include "SDL_opengl.h"

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
    SDL_Quit();
    exit(rc);
}

void *
get_funcaddr(const char *p)
{
    void *f = SDL_GL_GetProcAddress(p);
    if (f) {
        return f;
    } else {
        printf("Unable to get function pointer for %s\n", p);
        quit(1);
    }
    return NULL;
}

typedef struct
{
    void (APIENTRY * glBegin) (GLenum);
    void (APIENTRY * glEnd) ();
    void (APIENTRY * glVertex3f) (GLfloat, GLfloat, GLfloat);
    void (APIENTRY * glClearColor) (GLfloat, GLfloat, GLfloat, GLfloat);
    void (APIENTRY * glClear) (GLbitfield);
    void (APIENTRY * glDisable) (GLenum);
    void (APIENTRY * glEnable) (GLenum);
    void (APIENTRY * glColor4ub) (GLubyte, GLubyte, GLubyte, GLubyte);
    void (APIENTRY * glPointSize) (GLfloat);
    void (APIENTRY * glHint) (GLenum, GLenum);
    void (APIENTRY * glBlendFunc) (GLenum, GLenum);
    void (APIENTRY * glMatrixMode) (GLenum);
    void (APIENTRY * glLoadIdentity) ();
    void (APIENTRY * glOrtho) (GLdouble, GLdouble, GLdouble, GLdouble,
                               GLdouble, GLdouble);
    void (APIENTRY * glRotatef) (GLfloat, GLfloat, GLfloat, GLfloat);
    void (APIENTRY * glViewport) (GLint, GLint, GLsizei, GLsizei);
    void (APIENTRY * glFogf) (GLenum, GLfloat);
}
glfuncs;

void
init_glfuncs(glfuncs * f)
{
    f->glBegin = get_funcaddr("glBegin");
    f->glEnd = get_funcaddr("glEnd");
    f->glVertex3f = get_funcaddr("glVertex3f");
    f->glClearColor = get_funcaddr("glClearColor");
    f->glClear = get_funcaddr("glClear");
    f->glDisable = get_funcaddr("glDisable");
    f->glEnable = get_funcaddr("glEnable");
    f->glColor4ub = get_funcaddr("glColor4ub");
    f->glPointSize = get_funcaddr("glPointSize");
    f->glHint = get_funcaddr("glHint");
    f->glBlendFunc = get_funcaddr("glBlendFunc");
    f->glMatrixMode = get_funcaddr("glMatrixMode");
    f->glLoadIdentity = get_funcaddr("glLoadIdentity");
    f->glOrtho = get_funcaddr("glOrtho");
    f->glRotatef = get_funcaddr("glRotatef");
    f->glViewport = get_funcaddr("glViewport");
    f->glFogf = get_funcaddr("glFogf");
}

#define NB_PIXELS 1000

int
main(int argc, char *argv[])
{
    glfuncs f;
    int i;
    SDL_Event event;
    int done = 0;
    GLfloat pixels[NB_PIXELS * 3];
    const char *gl_library = NULL;      /* Use the default GL library */

    if (argv[1]) {
        gl_library = argv[1];
    }

    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        printf("Unable to init SDL : %s\n", SDL_GetError());
        return (1);
    }

    if (SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1) < 0) {
        printf("Unable to set GL attribute : %s\n", SDL_GetError());
        quit(1);
    }

    if (SDL_GL_LoadLibrary(gl_library) < 0) {
        printf("Unable to dynamically open GL lib : %s\n", SDL_GetError());
        quit(1);
    }

    if (SDL_SetVideoMode(640, 480, 0, SDL_OPENGL) == NULL) {
        printf("Unable to open video mode : %s\n", SDL_GetError());
        quit(1);
    }

    /* Set the window manager title bar */
    SDL_WM_SetCaption("SDL Dynamic OpenGL Loading Test", "testdyngl");

    init_glfuncs(&f);

    for (i = 0; i < NB_PIXELS; i++) {
        pixels[3 * i] = rand() % 250 - 125;
        pixels[3 * i + 1] = rand() % 250 - 125;
        pixels[3 * i + 2] = rand() % 250 - 125;
    }

    f.glViewport(0, 0, 640, 480);

    f.glMatrixMode(GL_PROJECTION);
    f.glLoadIdentity();
    f.glOrtho(-100, 100, -100, 100, -500, 500);

    f.glMatrixMode(GL_MODELVIEW);
    f.glLoadIdentity();

    f.glEnable(GL_DEPTH_TEST);
    f.glDisable(GL_TEXTURE_2D);
    f.glEnable(GL_BLEND);
    f.glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    f.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    f.glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    f.glEnable(GL_POINT_SMOOTH);
    f.glHint(GL_POINT_SMOOTH_HINT, GL_NICEST);
    f.glPointSize(5.0f);
    f.glEnable(GL_FOG);
    f.glFogf(GL_FOG_START, -500);
    f.glFogf(GL_FOG_END, 500);
    f.glFogf(GL_FOG_DENSITY, 0.005);

    do {
        f.glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        f.glRotatef(2.0, 1.0, 1.0, 1.0);
        f.glRotatef(1.0, 0.0, 1.0, 1.0);

        f.glColor4ub(255, 255, 255, 255);
        f.glBegin(GL_POINTS);
        for (i = 0; i < NB_PIXELS; i++) {
            f.glVertex3f(pixels[3 * i], pixels[3 * i + 1], pixels[3 * i + 2]);
        }
        f.glEnd();
        SDL_GL_SwapBuffers();

        while (SDL_PollEvent(&event)) {
            if (event.type == SDL_KEYDOWN)
                done = 1;
        }

        SDL_Delay(20);
    }
    while (!done);

    SDL_Quit();
    return 0;
}

#else /* HAVE_OPENGL */

int
main(int argc, char *argv[])
{
    printf("No OpenGL support on this system\n");
    return 1;
}

#endif /* HAVE_OPENGL */