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1 <HTML
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2 ><HEAD
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3 ><TITLE
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4 >Time Examples</TITLE
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5 ><META
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6 NAME="GENERATOR"
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7 CONTENT="Modular DocBook HTML Stylesheet Version 1.61
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8 "><LINK
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9 REL="HOME"
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10 TITLE="SDL Library Documentation"
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11 HREF="index.html"><LINK
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12 REL="UP"
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13 TITLE="Examples"
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14 HREF="guideexamples.html"><LINK
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15 REL="PREVIOUS"
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16 TITLE="CDROM Examples"
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17 HREF="guidecdromexamples.html"><LINK
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18 REL="NEXT"
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19 TITLE="SDL Reference"
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20 HREF="reference.html"></HEAD
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21 ><BODY
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22 CLASS="SECT1"
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23 BGCOLOR="#FFF8DC"
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24 TEXT="#000000"
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25 LINK="#0000ee"
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26 VLINK="#551a8b"
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27 ALINK="#ff0000"
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28 ><DIV
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29 CLASS="NAVHEADER"
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30 ><TABLE
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31 WIDTH="100%"
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32 BORDER="0"
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33 CELLPADDING="0"
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34 CELLSPACING="0"
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35 ><TR
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36 ><TH
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37 COLSPAN="3"
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38 ALIGN="center"
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39 >SDL Library Documentation</TH
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40 ></TR
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41 ><TR
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42 ><TD
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43 WIDTH="10%"
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44 ALIGN="left"
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45 VALIGN="bottom"
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46 ><A
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47 HREF="guidecdromexamples.html"
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48 >Prev</A
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49 ></TD
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50 ><TD
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51 WIDTH="80%"
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52 ALIGN="center"
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53 VALIGN="bottom"
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54 >Chapter 4. Examples</TD
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55 ><TD
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56 WIDTH="10%"
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57 ALIGN="right"
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58 VALIGN="bottom"
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59 ><A
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60 HREF="reference.html"
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61 >Next</A
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62 ></TD
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63 ></TR
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64 ></TABLE
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65 ><HR
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66 ALIGN="LEFT"
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67 WIDTH="100%"></DIV
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68 ><DIV
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69 CLASS="SECT1"
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70 ><H1
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71 CLASS="SECT1"
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72 ><A
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73 NAME="GUIDETIMEEXAMPLES"
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74 >Time Examples</A
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75 ></H1
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76 ><P
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77 ></P
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78 ><DIV
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79 CLASS="SECT2"
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80 ><H2
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81 CLASS="SECT2"
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82 ><A
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83 NAME="AEN373"
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84 >Time based game loop</A
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85 ></H2
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86 ><P
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87 ><PRE
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88 CLASS="PROGRAMLISTING"
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89 >#define TICK_INTERVAL 30
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90
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91 Uint32 TimeLeft(void)
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92 {
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93 static Uint32 next_time = 0;
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94 Uint32 now;
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95
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96 now = SDL_GetTicks();
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97 if ( next_time <= now ) {
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98 next_time = now+TICK_INTERVAL;
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99 return(0);
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100 }
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101 return(next_time-now);
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102 }
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103
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104
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105 /* main game loop
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106
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107 while ( game_running ) {
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108 UpdateGameState();
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109 SDL_Delay(TimeLeft());
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110 } </PRE
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111 ></P
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112 ></DIV
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113 ></DIV
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114 ><DIV
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115 CLASS="NAVFOOTER"
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116 ><HR
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117 ALIGN="LEFT"
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118 WIDTH="100%"><TABLE
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119 WIDTH="100%"
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120 BORDER="0"
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121 CELLPADDING="0"
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122 CELLSPACING="0"
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123 ><TR
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124 ><TD
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125 WIDTH="33%"
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126 ALIGN="left"
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127 VALIGN="top"
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128 ><A
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129 HREF="guidecdromexamples.html"
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130 >Prev</A
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131 ></TD
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132 ><TD
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133 WIDTH="34%"
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134 ALIGN="center"
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135 VALIGN="top"
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136 ><A
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137 HREF="index.html"
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138 >Home</A
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139 ></TD
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140 ><TD
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141 WIDTH="33%"
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142 ALIGN="right"
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143 VALIGN="top"
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144 ><A
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145 HREF="reference.html"
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146 >Next</A
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147 ></TD
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148 ></TR
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149 ><TR
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150 ><TD
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151 WIDTH="33%"
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152 ALIGN="left"
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153 VALIGN="top"
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154 >CDROM Examples</TD
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155 ><TD
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156 WIDTH="34%"
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157 ALIGN="center"
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158 VALIGN="top"
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159 ><A
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160 HREF="guideexamples.html"
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161 >Up</A
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162 ></TD
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163 ><TD
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164 WIDTH="33%"
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165 ALIGN="right"
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166 VALIGN="top"
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167 >SDL Reference</TD
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168 ></TR
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169 ></TABLE
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170 ></DIV
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171 ></BODY
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172 ></HTML
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173 > |
