git.mutantstargoat.com Git - ld42_outofspace/blob - src/gamescr.cc

   1 #include <vector>
   2 #include <gmath/gmath.h>
   3 #include "game.h"
   4 #include "screen.h"
   5 #include "opengl.h"
   6 #include "texture.h"
   7
   8 /* NOTES:
   9  * - whistle hhgg music
  10  * - colliding particles merge
  11  * - select objects and center camera on them
  12  */
  13
  14 struct Particle {
  15         float mass;
  16         Vec2 pos;
  17         Vec2 vel;
  18 };
  19
  20 struct Emitter {
  21         Vec2 pos;
  22         float mass;
  23         float rate, chunk;
  24         float angle, spread;
  25 };
  26
  27
  28 #define SIM_DT          0.016
  29
  30 #define GRID_SIZE       4096
  31 #define GRID_BITS       12
  32 #define GRID_X(idx)     (((idx) >> GRID_BITS) & (GRID_SIZE - 1))
  33 #define GRID_Y(idx)     ((idx) & (GRID_SIZE - 1))
  34
  35 #define FIELD_SIZE      2048
  36 #define MIN_CAM_DIST    1.0f
  37 #define MAX_CAM_DIST    350.0f
  38
  39 static int pos_to_grid(float x, float y);
  40
  41 static float grid[GRID_SIZE * GRID_SIZE];
  42 static Particle grid_part[GRID_SIZE * GRID_SIZE];
  43
  44 static std::vector<Emitter> emitters;
  45
  46 static Texture *grid_tex;
  47
  48 static float cam_theta;
  49 static float cam_dist = 100.0f;
  50 static Vec2 *targ_pos;
  51 static Mat4 view_matrix, proj_matrix;
  52
  53
  54 bool GameScreen::init()
  55 {
  56         grid_tex = new Texture;
  57         if(!grid_tex->load("data/purple_grid.png")) {
  58                 return false;
  59         }
  60         grid_tex->set_anisotropy(glcaps.max_aniso);
  61
  62         return true;
  63 }
  64
  65 void GameScreen::destroy()
  66 {
  67         delete grid_tex;
  68 }
  69
  70 static void simstep()
  71 {
  72 }
  73
  74 static void update()
  75 {
  76         static float interval;
  77
  78         interval += frame_dt;
  79         if(interval >= SIM_DT) {
  80                 interval -= SIM_DT;
  81                 simstep();
  82         }
  83
  84         // update projection matrix
  85         proj_matrix.perspective(deg_to_rad(60.0f), win_aspect, 0.5, 5000.0);
  86
  87         // update view matrix
  88         Vec3 targ;
  89         if(targ_pos) {
  90                 targ.x = targ_pos->x;
  91                 targ.z = targ_pos->y;
  92         }
  93
  94         float theta = -deg_to_rad(cam_theta);
  95         Vec3 camdir = Vec3(sin(theta) * cam_dist, pow(cam_dist * 0.1, 2.0) + 0.5, cos(theta) * cam_dist);
  96         Vec3 campos = targ + camdir;
  97
  98         view_matrix.inv_lookat(campos, targ, Vec3(0, 1, 0));
  99 }
 100
 101 void GameScreen::draw()
 102 {
 103         update();
 104
 105         glClearColor(0.01, 0.01, 0.01, 1);
 106         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 107
 108         glMatrixMode(GL_PROJECTION);
 109         glLoadMatrixf(proj_matrix[0]);
 110         glMatrixMode(GL_MODELVIEW);
 111         glLoadMatrixf(view_matrix[0]);
 112
 113         glPushAttrib(GL_ENABLE_BIT);
 114         glDisable(GL_LIGHTING);
 115         glDisable(GL_CULL_FACE);
 116
 117         glEnable(GL_TEXTURE_2D);
 118         bind_texture(grid_tex);
 119
 120         float maxu = FIELD_SIZE / 32.0f;
 121         float maxv = FIELD_SIZE / 32.0f;
 122         float hsz = FIELD_SIZE * 0.5f;
 123
 124         glBegin(GL_QUADS);
 125         glColor3f(1, 1, 1);
 126         glTexCoord2f(0, 0);
 127         glVertex3f(-hsz, 0, -hsz);
 128         glTexCoord2f(maxu, 0);
 129         glVertex3f(hsz, 0, -hsz);
 130         glTexCoord2f(maxu, maxv);
 131         glVertex3f(hsz, 0, hsz);
 132         glTexCoord2f(0, maxv);
 133         glVertex3f(-hsz, 0, hsz);
 134         glEnd();
 135
 136         glPopAttrib();
 137 }
 138
 139 void GameScreen::reshape(int x, int y)
 140 {
 141 }
 142
 143
 144
 145 void GameScreen::keyboard(int key, bool pressed)
 146 {
 147         if(pressed) {
 148                 switch(key) {
 149                 case KEY_ESC:
 150                         pop_screen();
 151                         break;
 152
 153                 default:
 154                         break;
 155                 }
 156         }
 157 }
 158
 159 static int prev_x, prev_y;
 160
 161 void GameScreen::mbutton(int bn, bool pressed, int x, int y)
 162 {
 163         prev_x = x;
 164         prev_y = y;
 165 }
 166
 167 void GameScreen::mmotion(int x, int y)
 168 {
 169         int dx = x - prev_x;
 170         int dy = y - prev_y;
 171         prev_x = x;
 172         prev_y = y;
 173
 174         if(game_bnstate(2)) {
 175                 cam_theta += dx * 0.5;
 176         }
 177 }
 178
 179 void GameScreen::mwheel(int dir, int x, int y)
 180 {
 181         cam_dist -= dir * cam_dist * 0.05f;
 182         if(cam_dist <= MIN_CAM_DIST) cam_dist = MIN_CAM_DIST;
 183         if(cam_dist > MAX_CAM_DIST) cam_dist = MAX_CAM_DIST;
 184 }