src/obj_sparkle.cxx

   1 /*
   2  * sparkle.cxx
   3  * Daniel Nelson - 9/5/0
   4  *
   5  * Copyright (C) 2000  Daniel Nelson
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  20  *
  21  * Daniel Nelson - aluminumangel.org
  22  * 174 W. 18th Ave.
  23  * Columbus, OH  43210
  24  *
  25  * Generates the display list and textures for the little sparkles!
  26  */
  27
  28 #include <GL/glut.h>
  29 #include <cmath>
  30
  31 #include "glext.h"
  32
  33 #include "Game.h"
  34 #include "Displayer.h"
  35
  36 GLuint Displayer::sparkle_list;
  37 GLuint Displayer::mote_textures[DC_NUMBER_MOTE_TYPES];
  38 GLuint Displayer::spark_texture;
  39
  40 void Displayer::generateSparkleList (   )
  41 {
  42   GLfloat texture[DC_SPARKLE_TEX_LENGTH][DC_SPARKLE_TEX_LENGTH][2];
  43
  44   sparkle_list = glGenLists(1);
  45
  46   glGenTextures(DC_NUMBER_MOTE_TYPES, mote_textures);
  47   spark_texture = mote_textures[MT_FOUR_POINTED_STAR];
  48
  49   for (int n = DC_NUMBER_MOTE_TYPES; n--; ) {
  50
  51     glBindTexture(GL_TEXTURE_2D, mote_textures[n]);
  52
  53     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
  54     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
  55     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  56     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  57
  58     for (int s = DC_SPARKLE_TEX_LENGTH; s--; )
  59       for (int t = DC_SPARKLE_TEX_LENGTH; t--; ) {
  60         float x = s * (2.0f / (float) (DC_SPARKLE_TEX_LENGTH - 1)) - 1.0f;
  61         float y = t * (2.0f / (float) (DC_SPARKLE_TEX_LENGTH - 1)) - 1.0f;
  62         float r = sqrt(x * x + y * y);
  63         float a = atan(y / x);
  64         float u;
  65         if (x < 0.0f) a = PI - a;
  66
  67         switch (n) {
  68         case MT_FOUR_POINTED_STAR:
  69           texture[s][t][0] = 0.3f * (1.0f - 2.5f * fabs(x * x - y * y))
  70            * exp(-r * r) / sqrt(r);
  71           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(r);
  72           break;
  73
  74         case MT_FIVE_POINTED_STAR:
  75           a *= 5.0f / 4.0f;
  76           r *= 1.4f;
  77           texture[s][t][0] = 0.3f * (1.0f - 2.5f
  78            * fabs(pow(r, 2.2f) * cos(a) * cos(a)
  79            - pow(r, 2.2f) * sin(a) * sin(a))) * exp(-r * r) / sqrt(r);
  80           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(r);
  81           break;
  82
  83         case MT_SIX_POINTED_STAR:
  84           a *= 6.0f / 4.0f;
  85           r *= 1.4f;
  86           texture[s][t][0] = 0.3f * (1.0f - 2.5f
  87            * fabs(pow(r, 2.2f) * cos(a) * cos(a)
  88            - pow(r, 2.2f) * sin(a) * sin(a))) * exp(-r * r) / sqrt(r);
  89           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(r);
  90           break;
  91
  92         case MT_SPECIAL_STAR:
  93           a *= 8.0f / 4.0f;
  94           r *= 1.4f;
  95           texture[s][t][0] = 0.3f * (1.0f - 2.5f
  96            * fabs(pow(r, 4.2f) * cos(a) * cos(a)
  97            - pow(r, 4.2f) * sin(a) * sin(a))) * exp(-r * r) / sqrt(r);
  98           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(r);
  99           break;
 100
 101         case MT_MULTIPLIER_ONE_STAR:
 102           a *= 3.0f / 4.0f;
 103           r *= 1.9f;
 104           texture[s][t][0] = 0.3f * (1.0f - 2.5f
 105            * fabs(pow(r, 1.5f) * cos(a) * cos(a)
 106            - pow(r, 1.5f) * sin(a) * sin(a))) * exp(-r * r) / sqrt(r);
 107
 108           if (r < 1.0f) {
 109             a += PI / 4.0f;
 110             u = 0.3f * (1.0f - 2.5f * fabs(pow(r, 0.7f) * cos(a) * cos(a)
 111              - pow(r, 0.7f) * sin(a) * sin(a))) * exp(-0.3f * r * r) / sqrt(r);
 112             if (u > 0.0f) texture[s][t][0] += u;
 113             if (texture[s][t][0] > 0.5f)
 114               texture[s][t][0] *= 0.3f + 0.7f / (0.5f + texture[s][t][0]);
 115           }
 116
 117           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(r);
 118           break;
 119
 120         case MT_MULTIPLIER_TWO_STAR:
 121           texture[s][t][0] = 0.3f * (1.0f - 2.5f * fabs(x * x - y * y))
 122            * exp(-r * r) / sqrt(r);
 123
 124           a += PI / 4.0f;
 125           u = 0.3f * (1.0f - 2.5f * fabs(pow(r, 0.7f) * cos(a) * cos(a)
 126            - pow(r, 0.7f) * sin(a) * sin(a))) * exp(-0.1f * r * r) / sqrt(r);
 127           if (u > 0.0f) texture[s][t][0] += u;
 128           if (texture[s][t][0] > 0.5f)
 129             texture[s][t][0] *= 0.3f + 0.7f / (0.5f + texture[s][t][0]);
 130
 131           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(r);
 132           break;
 133
 134         case MT_MULTIPLIER_THREE_STAR:
 135           a += PI / 4.0f;
 136           u = 0.3f * (1.0f - 3.1f * fabs(pow(r, 0.2f) * cos(a) * cos(a)
 137            - pow(r, 0.2f) * sin(a) * sin(a))) * exp(-0.1f * r * r) / sqrt(r);
 138           if (u > 0.0f)
 139             texture[s][t][0] = u;
 140           else
 141             texture[s][t][0] = 0.0f;
 142
 143           texture[s][t][0] += 0.3f * (1.0f - 6.0f * fabs(x * x - y * y))
 144            * exp(-0.4 * r * r) / sqrt(2.0 * r);
 145           if (texture[s][t][0] > 0.5f)
 146             texture[s][t][0] *= 0.3f + 0.7f / (0.5f + texture[s][t][0]);
 147
 148           texture[s][t][1] = 4.5f * texture[s][t][0] * sqrt(2 * r);
 149
 150           u = 0.15f * exp(-350.0f * (r - 0.9f) * (r - 0.9f))
 151            * (1.15f + 0.3f * cos(4.0f * a));
 152
 153           if (u > texture[s][t][0]) {
 154             texture[s][t][0] = u;
 155             texture[s][t][1] = 4.5f * u;
 156           }
 157           break;
 158         }
 159       }
 160
 161     glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE_ALPHA, DC_SPARKLE_TEX_LENGTH,
 162      DC_SPARKLE_TEX_LENGTH, GL_FALSE, GL_LUMINANCE_ALPHA, GL_FLOAT, texture);
 163   }
 164
 165   glNewList(sparkle_list, GL_COMPILE);
 166     glBegin(GL_TRIANGLE_STRIP);
 167
 168       glTexCoord2f(0.0f, 0.0f);
 169       glVertex3f(-DC_SPARKLE_LENGTH, -DC_SPARKLE_LENGTH, 0.0f);
 170       glTexCoord2f(1.0f, 0.0f);
 171       glVertex3f(DC_SPARKLE_LENGTH, -DC_SPARKLE_LENGTH, 0.0f);
 172       glTexCoord2f(0.0f, 1.0f);
 173       glVertex3f(-DC_SPARKLE_LENGTH, DC_SPARKLE_LENGTH, 0.0f);
 174       glTexCoord2f(1.0f, 1.0f);
 175       glVertex3f(DC_SPARKLE_LENGTH, DC_SPARKLE_LENGTH, 0.0f);
 176
 177     glEnd();
 178   glEndList();
 179 }