Amiga Magazin: Amiga-CD 2000 April & May/AMIGA_2000_04.iso/patches/mesa3.1/samples.tk/point.c

C/C++ Source or Header | 1998-05-13 | 5KB | 229 lines

/*
 * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the name of
 * Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Silicon Graphics.
 *
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
 * ANY KIND,
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 *
 * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "gltk.h"

#define CI_RED TK_RED
#define CI_ANTI_ALIAS_GREEN 16
#define CI_ANTI_ALIAS_YELLOW 32
#define CI_ANTI_ALIAS_RED 48

GLenum rgb, doubleBuffer, directRender, windType;
GLint windW, windH;

GLenum mode;
GLint size;
float point[3] =
{
  1.0, 1.0, 0.0
};

static void Init(void)
{
  GLint i;

  glClearColor(0.0, 0.0, 0.0, 0.0);

  glBlendFunc(GL_SRC_ALPHA, GL_ZERO);

  if (!rgb) {
    for (i = 0; i < 16; i++) {
      tkSetOneColor(i + CI_ANTI_ALIAS_RED, i / 15.0, 0.0, 0.0);
      tkSetOneColor(i + CI_ANTI_ALIAS_YELLOW, i / 15.0, i / 15.0, 0.0);
      tkSetOneColor(i + CI_ANTI_ALIAS_GREEN, 0.0, i / 15.0, 0.0);
    }
  }

  mode = GL_FALSE;
  size = 1;
}

static void Reshape(int width, int height)
{

  windW = (GLint) width;
  windH = (GLint) height;

  glViewport(0, 0, width, height);

  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluOrtho2D(-windW / 2, windW / 2, -windH / 2, windH / 2);
  glMatrixMode(GL_MODELVIEW);
}

static GLenum Key(int key, GLenum mask)
{

  switch (key) {
    case TK_ESCAPE:
      tkQuit();
    case TK_1:
      mode = !mode;
      break;
    case TK_W:
      size++;
      break;
    case TK_w:
      size--;
      if (size < 1) {
    size = 1;
      }
      break;
    case TK_LEFT:
      point[0] -= 0.25;
      break;
    case TK_RIGHT:
      point[0] += 0.25;
      break;
    case TK_UP:
      point[1] += 0.25;
      break;
    case TK_DOWN:
      point[1] -= 0.25;
      break;
    default:
      return GL_FALSE;
  }
  return GL_TRUE;
}

static void Draw(void)
{

  glClear(GL_COLOR_BUFFER_BIT);

  TK_SETCOLOR(windType, TK_YELLOW);
  glBegin(GL_LINE_STRIP);
  glVertex2f(-windW / 2, 0);
  glVertex2f(windW / 2, 0);
  glEnd();
  glBegin(GL_LINE_STRIP);
  glVertex2f(0, -windH / 2);
  glVertex2f(0, windH / 2);
  glEnd();

  if (mode) {
    glEnable(GL_BLEND);
    glEnable(GL_POINT_SMOOTH);
  }
  else {
    glDisable(GL_BLEND);
    glDisable(GL_POINT_SMOOTH);
  }

  glPointSize(size);
  if (mode) {
    (rgb) ? glColor3f(1.0, 0.0, 0.0) : glIndexf(CI_ANTI_ALIAS_RED);
  }
  else {
    (rgb) ? glColor3f(1.0, 0.0, 0.0) : glIndexf(CI_RED);
  }
  glBegin(GL_POINTS);
  glVertex3fv(point);
  glEnd();

  glDisable(GL_POINT_SMOOTH);
  glDisable(GL_BLEND);

  glPointSize(1);
  TK_SETCOLOR(windType, TK_GREEN);
  glBegin(GL_POINTS);
  glVertex3fv(point);
  glEnd();

  glFlush();

  if (doubleBuffer) {
    tkSwapBuffers();
  }
}

static GLenum Args(int argc, char **argv)
{
  GLint i;

  rgb = GL_TRUE;
  doubleBuffer = GL_FALSE;
  directRender = GL_TRUE;

  for (i = 1; i < argc; i++) {
    if (strcmp(argv[i], "-ci") == 0) {
      rgb = GL_FALSE;
    }
    else if (strcmp(argv[i], "-rgb") == 0) {
      rgb = GL_TRUE;
    }
    else if (strcmp(argv[i], "-sb") == 0) {
      doubleBuffer = GL_FALSE;
    }
    else if (strcmp(argv[i], "-db") == 0) {
      doubleBuffer = GL_TRUE;
    }
    else if (strcmp(argv[i], "-dr") == 0) {
      directRender = GL_TRUE;
    }
    else if (strcmp(argv[i], "-ir") == 0) {
      directRender = GL_FALSE;
    }
    else {
      printf("%s (Bad option).\n", argv[i]);
      return GL_FALSE;
    }
  }
  return GL_TRUE;
}

void main(int argc, char **argv)
{

  if (Args(argc, argv) == GL_FALSE) {
    tkQuit();
  }

  windW = 300;
  windH = 300;
  tkInitPosition(0, 0, windW, windH);

  windType = (rgb) ? TK_RGB : TK_INDEX;
  windType |= (doubleBuffer) ? TK_DOUBLE : TK_SINGLE;
  windType |= (directRender) ? TK_DIRECT : TK_INDIRECT;
  tkInitDisplayMode(windType);

  if (tkInitWindow("Point Test") == GL_FALSE) {
    tkQuit();
  }

  Init();

  tkExposeFunc(Reshape);
  tkReshapeFunc(Reshape);
  tkKeyDownFunc(Key);
  tkDisplayFunc(Draw);
  tkExec();
}