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annotate dox/define_backend.h @ 847:dfe28355bded

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Fix the location of the text elements.
author wycc
date Sun, 19 Sep 2010 19:28:33 +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
Thinker K.F. Li <thinker@branda.to>
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2 *
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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3 * A backend is factory to initialize environment to make
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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4 * MadBufferfly available. A backend should provide resources
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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5 * needed by MadButterfly, for example, to provide a surface
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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6 * that will show everything drawing on it. It also translate and
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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7 * relay input events, mouse or keyboard, to MadButterfly.
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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8 * The tasks that a backend should do are listed following,
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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9 * - to prepare a backend surface,
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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10 * - to prepare a front surface,
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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11 * - to translate and relay input events to MadButterfly,
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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12 * - to handle a timer, and relay timeout events to MadButterfly.
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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13 *
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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14 * The output device surface for X Window is a surface return by
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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15 * cairo_xlib_surface_create(). MadButterfly will copy everything
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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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
Thinker K.F. Li <thinker@branda.to>
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18 * between X client and server can be large. For this situation,
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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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
Thinker K.F. Li <thinker@branda.to>
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20 * front surface to backend surface after completion of a series
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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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
Thinker K.F. Li <thinker@branda.to>
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23 *
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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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
Thinker K.F. Li <thinker@branda.to>
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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.
1f900a67bd38 Doc How to Define a Backend
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27 *
1f900a67bd38 Doc How to Define a Backend
Thinker K.F. Li <thinker@branda.to>
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28 * \see X_supp.c
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29 */