[sdl_omap.git] / docs / html / sdldisplayformatalpha.html

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>SDL_DisplayFormatAlpha</TITLE
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></A
>SDL_DisplayFormatAlpha</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2432"
></A
><H2
>Name</H2
>SDL_DisplayFormatAlpha&nbsp;--&nbsp;Convert a surface to the display format</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN2435"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN2436"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_Surface *<B
CLASS="FSFUNC"
>SDL_DisplayFormatAlpha</B
></CODE
>(SDL_Surface *surface);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2442"
></A
><H2
>Description</H2
><P
>This function takes a surface and copies it to a new surface of the
pixel format and colors of the video framebuffer plus an alpha channel,
suitable for fast blitting onto the display surface.  It calls
<A
HREF="sdlconvertsurface.html"
>SDL_ConvertSurface</A
></P
><P
>If you want to take advantage of hardware colorkey or alpha blit
acceleration, you should set the colorkey and alpha value before
calling this function.</P
><P
>This function can be used to convert a colourkey to an alpha channel,
if the <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> flag is set on the surface.
The generated surface will then be transparent (alpha=0) where the
pixels match the colourkey, and opaque (alpha=255) elsewhere.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2449"
></A
><H2
>Return Value</H2
><P
>If the conversion fails or runs out of memory, it returns
<SPAN
CLASS="RETURNVALUE"
>NULL</SPAN
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2453"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlconvertsurface.html"
>SDL_ConvertSurface</A
>,
<A
HREF="sdlsetalpha.html"
>SDL_SetAlpha</A
>,
<A
HREF="sdlsetcolorkey.html"
>SDL_SetColorKey</A
>,
<A
HREF="sdldisplayformat.html"
>SDL_DisplayFormat</A
>,
<A
HREF="sdlsurface.html"
>SDL_Surface</A
></P
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Commit	Line	Data
e14743d1	1	<HTML
	2	><HEAD
	3	><TITLE
	4	>SDL_DisplayFormatAlpha</TITLE
	5	><META
	6	NAME="GENERATOR"
	7	CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
	8	"><LINK
	9	REL="HOME"
	10	TITLE="SDL Library Documentation"
	11	HREF="index.html"><LINK
	12	REL="UP"
	13	TITLE="Video"
	14	HREF="video.html"><LINK
	15	REL="PREVIOUS"
	16	TITLE="SDL_DisplayFormat"
	17	HREF="sdldisplayformat.html"><LINK
	18	REL="NEXT"
	19	TITLE="SDL_WarpMouse"
	20	HREF="sdlwarpmouse.html"></HEAD
	21	><BODY
	22	CLASS="REFENTRY"
	23	BGCOLOR="#FFF8DC"
	24	TEXT="#000000"
	25	LINK="#0000ee"
	26	VLINK="#551a8b"
	27	ALINK="#ff0000"
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	29	CLASS="NAVHEADER"
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	31	SUMMARY="Header navigation table"
	32	WIDTH="100%"
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	39	ALIGN="center"
	40	>SDL Library Documentation</TH
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	42	><TR
	43	><TD
	44	WIDTH="10%"
	45	ALIGN="left"
	46	VALIGN="bottom"
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	48	HREF="sdldisplayformat.html"
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	50	>Prev</A
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	64	>Next</A
65	></TD
66	></TR
67	></TABLE
68	><HR
69	ALIGN="LEFT"
70	WIDTH="100%"></DIV
71	><H1
72	><A
73	NAME="SDLDISPLAYFORMATALPHA"
74	></A
75	>SDL_DisplayFormatAlpha</H1
76	><DIV
77	CLASS="REFNAMEDIV"
78	><A
79	NAME="AEN2432"
80	></A
81	><H2
82	>Name</H2
83	>SDL_DisplayFormatAlpha -- Convert a surface to the display format</DIV
84	><DIV
85	CLASS="REFSYNOPSISDIV"
86	><A
87	NAME="AEN2435"
88	></A
89	><H2
90	>Synopsis</H2
91	><DIV
92	CLASS="FUNCSYNOPSIS"
93	><A
94	NAME="AEN2436"
95	></A
96	><P
97	></P
98	><PRE
99	CLASS="FUNCSYNOPSISINFO"
100	>#include "SDL.h"</PRE
101	><P
102	><CODE
103	><CODE
104	CLASS="FUNCDEF"
105	>SDL_Surface *<B
106	CLASS="FSFUNC"
107	>SDL_DisplayFormatAlpha</B
108	></CODE
109	>(SDL_Surface *surface);</CODE
110	></P
111	><P
112	></P
113	></DIV
114	></DIV
115	><DIV
116	CLASS="REFSECT1"
117	><A
118	NAME="AEN2442"
119	></A
120	><H2
121	>Description</H2
122	><P
123	>This function takes a surface and copies it to a new surface of the
124	pixel format and colors of the video framebuffer plus an alpha channel,
125	suitable for fast blitting onto the display surface. It calls
126	<A
127	HREF="sdlconvertsurface.html"
128	>SDL_ConvertSurface</A
129	></P
130	><P
131	>If you want to take advantage of hardware colorkey or alpha blit
132	acceleration, you should set the colorkey and alpha value before
133	calling this function.</P
134	><P
135	>This function can be used to convert a colourkey to an alpha channel,
136	if the <TT
137	CLASS="LITERAL"
138	>SDL_SRCCOLORKEY</TT
139	> flag is set on the surface.
140	The generated surface will then be transparent (alpha=0) where the
141	pixels match the colourkey, and opaque (alpha=255) elsewhere.</P
142	></DIV
143	><DIV
144	CLASS="REFSECT1"
145	><A
146	NAME="AEN2449"
147	></A
148	><H2
149	>Return Value</H2
150	><P
151	>If the conversion fails or runs out of memory, it returns
152	<SPAN
153	CLASS="RETURNVALUE"
154	>NULL</SPAN
155	></P
156	></DIV
157	><DIV
158	CLASS="REFSECT1"
159	><A
160	NAME="AEN2453"
161	></A
162	><H2
163	>See Also</H2
164	><P
165	><A
166	HREF="sdlconvertsurface.html"
167	>SDL_ConvertSurface</A
168	>,
169	<A
170	HREF="sdlsetalpha.html"
171	>SDL_SetAlpha</A
172	>,
173	<A
174	HREF="sdlsetcolorkey.html"
175	>SDL_SetColorKey</A
176	>,
177	<A
178	HREF="sdldisplayformat.html"
179	>SDL_DisplayFormat</A
180	>,
181	<A
182	HREF="sdlsurface.html"
183	>SDL_Surface</A
184	></P
185	></DIV
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187	CLASS="NAVFOOTER"
188	><HR
189	ALIGN="LEFT"
190	WIDTH="100%"><TABLE
191	SUMMARY="Footer navigation table"
192	WIDTH="100%"
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198	WIDTH="33%"
199	ALIGN="left"
200	VALIGN="top"
201	><A
202	HREF="sdldisplayformat.html"
203	ACCESSKEY="P"
204	>Prev</A
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207	WIDTH="34%"
208	ALIGN="center"
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211	HREF="index.html"
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213	>Home</A
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216	WIDTH="33%"
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226	><TD
227	WIDTH="33%"
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230	>SDL_DisplayFormat</TD
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237	ACCESSKEY="U"
238	>Up</A
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248	></BODY
249	></HTML
250	>