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56 >Chapter 4. Examples</TD |
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76 NAME="GUIDETIMEEXAMPLES" |
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77 ></A |
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78 >Time Examples</H1 |
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79 ><P |
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80 ></P |
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82 CLASS="SECT2" |
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83 ><H2 |
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84 CLASS="SECT2" |
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86 NAME="AEN412" |
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87 ></A |
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88 >Time based game loop</H2 |
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89 ><P |
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90 ><PRE |
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91 CLASS="PROGRAMLISTING" |
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92 >#define TICK_INTERVAL 30 |
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93 |
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94 static Uint32 next_time; |
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95 |
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96 Uint32 time_left(void) |
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97 { |
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98 Uint32 now; |
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99 |
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100 now = SDL_GetTicks(); |
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101 if(next_time <= now) |
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102 return 0; |
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103 else |
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104 return next_time - now; |
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105 } |
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106 |
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107 |
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108 /* main game loop */ |
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109 |
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110 next_time = SDL_GetTicks() + TICK_INTERVAL; |
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111 while ( game_running ) { |
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112 update_game_state(); |
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113 SDL_Delay(time_left()); |
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114 next_time += TICK_INTERVAL; |
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115 } </PRE |
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