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 /** Display Management (Display) */
18 /** */
19 /**************************************************************************/
20 #define GX_SOURCE_CODE
21
22 /* Include necessary system files. */
23
24 #include "gx_api.h"
25 #include "gx_display.h"
26
27 /**************************************************************************/
28 /* */
29 /* FUNCTION RELEASE */
30 /* */
31 /* _gx_display_driver_24xrgb_rotated_pixel_blend PORTABLE C */
32 /* 6.1.4 */
33 /* AUTHOR */
34 /* */
35 /* Kenneth Maxwell, Microsoft Corporation */
36 /* */
37 /* DESCRIPTION */
38 /* */
39 /* Rotated pixel blend function for 24xrgb color format. */
40 /* */
41 /* INPUT */
42 /* */
43 /* context Drawing context */
44 /* x X coordinate */
45 /* y Y coordinate */
46 /* color Color of line to write */
47 /* alpha Alpha value */
48 /* */
49 /* OUTPUT */
50 /* */
51 /* None */
52 /* */
53 /* CALLS */
54 /* */
55 /* REDVAL_24BPP Extract the red component */
56 /* GREENVAL_24BPP Extract the green component */
57 /* BLUEVAL_24BPP Extract the blue component */
58 /* ASSEMBLECOLOR_24BPP Assemble color components */
59 /* */
60 /* CALLED BY */
61 /* */
62 /* GUIX Internal Code */
63 /* */
64 /* RELEASE HISTORY */
65 /* */
66 /* DATE NAME DESCRIPTION */
67 /* */
68 /* 02-02-2021 Kenneth Maxwell Initial Version 6.1.4 */
69 /* */
70 /**************************************************************************/
_gx_display_driver_24xrgb_rotated_pixel_blend(GX_DRAW_CONTEXT * context,INT x,INT y,GX_COLOR fcolor,GX_UBYTE alpha)71 VOID _gx_display_driver_24xrgb_rotated_pixel_blend(GX_DRAW_CONTEXT *context, INT x, INT y, GX_COLOR fcolor, GX_UBYTE alpha)
72 {
73 GX_UBYTE fred, fgreen, fblue;
74 GX_UBYTE bred, bgreen, bblue;
75 GX_UBYTE balpha;
76 ULONG bcolor;
77 ULONG *put;
78
79
80 /* Is the pixel non-transparent? */
81 if (alpha > 0)
82 {
83 /* Calculate address of pixel. */
84 put = (ULONG *)context -> gx_draw_context_memory;
85
86 if (context -> gx_draw_context_display -> gx_display_rotation_angle == GX_SCREEN_ROTATION_CW)
87 {
88 put += context -> gx_draw_context_pitch * (context -> gx_draw_context_canvas -> gx_canvas_x_resolution - x - 1);
89 put += y;
90 }
91 else
92 {
93 put += context -> gx_draw_context_pitch * x;
94 put += (context -> gx_draw_context_canvas -> gx_canvas_y_resolution - y - 1);
95 }
96
97 /* No need to blend if alpha value is 255. */
98 if (alpha == 255)
99 {
100 *put = (ULONG)(fcolor | 0xff000000);
101
102 return;
103 }
104
105 /* Split foreground into red, green, and blue components. */
106 fred = REDVAL_24BPP(fcolor);
107 fgreen = GREENVAL_24BPP(fcolor);
108 fblue = BLUEVAL_24BPP(fcolor);
109
110 /* Read background color. */
111 bcolor = *put;
112
113 /* Split background color into red, green, and blue components. */
114 bred = REDVAL_24BPP(bcolor);
115 bgreen = GREENVAL_24BPP(bcolor);
116 bblue = BLUEVAL_24BPP(bcolor);
117
118 /* Background alpha is inverse of foreground alpha. */
119 balpha = (GX_UBYTE)(256 - alpha);
120
121 /* Blend foreground and background, each color channel. */
122 fred = (GX_UBYTE)(((bred * balpha) + (fred * alpha)) >> 8);
123 fgreen = (GX_UBYTE)(((bgreen * balpha) + (fgreen * alpha)) >> 8);
124 fblue = (GX_UBYTE)(((bblue * balpha) + (fblue * alpha)) >> 8);
125
126 /* Re-assemble into 32-bit color and write it out. */
127 *put = (ULONG)(ASSEMBLECOLOR_32ARGB(0xff, fred, fgreen, fblue));
128 }
129 }
130
131
