1 /***************************************************************************
2  * Copyright (c) 2024 Microsoft Corporation
3  *
4  * This program and the accompanying materials are made available under the
5  * terms of the MIT License which is available at
6  * https://opensource.org/licenses/MIT.
7  *
8  * SPDX-License-Identifier: MIT
9  **************************************************************************/
10 
11 
12 /**************************************************************************/
13 /**************************************************************************/
14 /**                                                                       */
15 /** GUIX Component                                                        */
16 /**                                                                       */
17 /**   Canvas Management (Canvas)                                          */
18 /**                                                                       */
19 /**************************************************************************/
20 
21 #define GX_SOURCE_CODE
22 
23 /* Include necessary system files.  */
24 
25 #include "gx_api.h"
26 #include "gx_system.h"
27 #include "gx_utility.h"
28 #include "gx_canvas.h"
29 
30 /**************************************************************************/
31 /*                                                                        */
32 /*  FUNCTION                                               RELEASE        */
33 /*                                                                        */
34 /*    _gx_utility_alphamap_create                         PORTABLE C      */
35 /*                                                           6.1          */
36 /*  AUTHOR                                                                */
37 /*                                                                        */
38 /*    Kenneth Maxwell, Microsoft Corporation                              */
39 /*                                                                        */
40 /*  DESCRIPTION                                                           */
41 /*                                                                        */
42 /*    This function creates an 8bpp alpha-map pixelmap.                   */
43 /*                                                                        */
44 /*  INPUT                                                                 */
45 /*                                                                        */
46 /*    width                                 width of desired alphamap     */
47 /*    height                                height of desired alphamap    */
48 /*    map                                   pointer to pixlmap structure  */
49 /*                                                                        */
50 /*  OUTPUT                                                                */
51 /*                                                                        */
52 /*    status                                Completion status             */
53 /*                                                                        */
54 /*  CALLS                                                                 */
55 /*                                                                        */
56 /*    _gx_system_memory_allocator           Dynamically allocate memory   */
57 /*                                                                        */
58 /*  CALLED BY                                                             */
59 /*                                                                        */
60 /*    _gx_utility_string_to_alphamap                                      */
61 /*    application software                                                */
62 /*                                                                        */
63 /*  RELEASE HISTORY                                                       */
64 /*                                                                        */
65 /*    DATE              NAME                      DESCRIPTION             */
66 /*                                                                        */
67 /*  05-19-2020     Kenneth Maxwell          Initial Version 6.0           */
68 /*  09-30-2020     Kenneth Maxwell          Modified comment(s),          */
69 /*                                            resulting in version 6.1    */
70 /*                                                                        */
71 /**************************************************************************/
_gx_utility_alphamap_create(INT width,INT height,GX_PIXELMAP * map)72 UINT _gx_utility_alphamap_create(INT width, INT height, GX_PIXELMAP *map)
73 {
74 /* try to allocate memory for alphamap */
75 GX_UBYTE *memptr;
76 ULONG     memsize = (ULONG)(width * height);
77 
78     if (width > GX_MAX_PIXELMAP_RESOLUTION)
79     {
80         return GX_INVALID_WIDTH;
81     }
82 
83     if (height > GX_MAX_PIXELMAP_RESOLUTION)
84     {
85         return GX_INVALID_HEIGHT;
86     }
87 
88     if (!memsize || _gx_system_memory_allocator == GX_NULL)
89     {
90         return GX_FAILURE;
91     }
92 
93     memptr = (GX_UBYTE *)(_gx_system_memory_allocator(memsize));
94 
95     if (memptr == GX_NULL)
96     {
97         map -> gx_pixelmap_data = GX_NULL;
98         return GX_FAILURE;
99     }
100 
101     map -> gx_pixelmap_aux_data = GX_NULL;
102     map -> gx_pixelmap_aux_data_size = 0;
103     map -> gx_pixelmap_data = memptr;
104     map -> gx_pixelmap_data_size = memsize;
105     map -> gx_pixelmap_flags = GX_PIXELMAP_TRANSPARENT;
106     map -> gx_pixelmap_transparent_color = 0;
107     map -> gx_pixelmap_format = GX_COLOR_FORMAT_8BIT_ALPHAMAP;
108     map -> gx_pixelmap_height = (GX_VALUE)height;
109     map -> gx_pixelmap_width = (GX_VALUE)width;
110     map -> gx_pixelmap_version_major = map -> gx_pixelmap_version_minor = 0;
111     memset(memptr, 0, (size_t)memsize);
112     return GX_SUCCESS;
113 }
114 
115