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annotate dox/define_backend.h @ 795:46a4cd4d382b

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Remove dependent on system time to gain frame rate Date.now() would read system time. It is ineffeciency in for some implementation. To gain frame rate, we should rely on accuration of setInterval().
author Thinker K.F. Li <thinker@codemud.net>
date Tue, 31 Aug 2010 10:04:15 +0800
parents 1f900a67bd38
children 5dedeedf0408
rev   line source
443
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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1 /*! \page backend How to Define a Backend
1f900a67bd38 Doc How to Define a Backend
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2 *
1f900a67bd38 Doc How to Define a Backend
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3 * A backend is factory to initialize environment to make
1f900a67bd38 Doc How to Define a Backend
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4 * MadBufferfly available. A backend should provide resources
1f900a67bd38 Doc How to Define a Backend
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5 * needed by MadButterfly, for example, to provide a surface
1f900a67bd38 Doc How to Define a Backend
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6 * that will show everything drawing on it. It also translate and
1f900a67bd38 Doc How to Define a Backend
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7 * relay input events, mouse or keyboard, to MadButterfly.
1f900a67bd38 Doc How to Define a Backend
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8 * The tasks that a backend should do are listed following,
1f900a67bd38 Doc How to Define a Backend
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9 * - to prepare a backend surface,
1f900a67bd38 Doc How to Define a Backend
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10 * - to prepare a front surface,
1f900a67bd38 Doc How to Define a Backend
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11 * - to translate and relay input events to MadButterfly,
1f900a67bd38 Doc How to Define a Backend
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12 * - to handle a timer, and relay timeout events to MadButterfly.
1f900a67bd38 Doc How to Define a Backend
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13 *
1f900a67bd38 Doc How to Define a Backend
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14 * The output device surface for X Window is a surface return by
1f900a67bd38 Doc How to Define a Backend
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15 * cairo_xlib_surface_create(). MadButterfly will copy everything
1f900a67bd38 Doc How to Define a Backend
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16 * from front surface to backend surface to show graphy to user.
1f900a67bd38 Doc How to Define a Backend
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17 * The copying is to avoid user find slowly redrawing. The latency
1f900a67bd38 Doc How to Define a Backend
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18 * between X client and server can be large. For this situation,
1f900a67bd38 Doc How to Define a Backend
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19 * we need a font surface as a buffer drawing, and copy image from
1f900a67bd38 Doc How to Define a Backend
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20 * front surface to backend surface after completion of a series
1f900a67bd38 Doc How to Define a Backend
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21 * of drawing. A front surface can be an image surface for this
1f900a67bd38 Doc How to Define a Backend
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22 * situation.
1f900a67bd38 Doc How to Define a Backend
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23 *
1f900a67bd38 Doc How to Define a Backend
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24 * The input events of X Window should be translated to raw events of
1f900a67bd38 Doc How to Define a Backend
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25 * MadButterfly and sent them to rdman through notify_coord_or_shape()
1f900a67bd38 Doc How to Define a Backend
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26 * function.
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27 *
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28 * \see X_supp.c
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29 */