1/*****************************************************************************/
2/* */
3/* vic2sprite.c */
4/* */
5/* VICII sprite format backend for the sp65 sprite and bitmap utility */
6/* */
7/* */
8/* */
9/* (C) 2012, Ullrich von Bassewitz */
10/* Roemerstrasse 52 */
11/* D-70794 Filderstadt */
12/* EMail: uz@cc65.org */
13/* */
14/* */
15/* This software is provided 'as-is', without any expressed or implied */
16/* warranty. In no event will the authors be held liable for any damages */
17/* arising from the use of this software. */
18/* */
19/* Permission is granted to anyone to use this software for any purpose, */
20/* including commercial applications, and to alter it and redistribute it */
21/* freely, subject to the following restrictions: */
22/* */
23/* 1. The origin of this software must not be misrepresented; you must not */
24/* claim that you wrote the original software. If you use this software */
25/* in a product, an acknowledgment in the product documentation would be */
26/* appreciated but is not required. */
27/* 2. Altered source versions must be plainly marked as such, and must not */
28/* be misrepresented as being the original software. */
29/* 3. This notice may not be removed or altered from any source */
30/* distribution. */
31/* */
32/*****************************************************************************/
33
34
35
36/* common */
37#include "attrib.h"
38#include "print.h"
39
40/* sp65 */
41#include "attr.h"
42#include "error.h"
43#include "vic2sprite.h"
44
45
46
47/*****************************************************************************/
48/* Data */
49/*****************************************************************************/
50
51
52
53/* Sprite mode */
54enum Mode {
55 smAuto,
56 smHighRes,
57 smMultiColor
58};
59
60/* Size of a sprite */
61#define WIDTH_HR 24U
62#define WIDTH_MC 12U
63#define HEIGHT 21U
64
65
66
67/*****************************************************************************/
68/* Code */
69/*****************************************************************************/
70
71
72
73static enum Mode GetMode (const Collection* A)
74/* Return the sprite mode from the attribute collection A */
75{
76 /* Check for a mode attribute */
77 const char* Mode = GetAttrVal (A, "mode");
78 if (Mode) {
79 if (strcmp (Mode, "highres") == 0) {
80 return smHighRes;
81 } else if (strcmp (Mode, "multicolor") == 0) {
82 return smMultiColor;
83 } else {
84 Error ("Invalid value for attribute 'mode'");
85 }
86 }
87
88 return smAuto;
89}
90
91
92
93StrBuf* GenVic2Sprite (const Bitmap* B, const Collection* A)
94/* Generate binary output in VICII sprite format for the bitmap B. The output
95** is stored in a string buffer (which is actually a dynamic char array) and
96** returned.
97*/
98{
99 enum Mode M;
100 StrBuf* D;
101 unsigned X, Y;
102
103
104 /* Output the image properties */
105 Print (stdout, 1, "Image is %ux%u with %u colors%s\n",
106 GetBitmapWidth (B), GetBitmapHeight (B), GetBitmapColors (B),
107 BitmapIsIndexed (B)? " (indexed)" : "");
108
109 /* Get the sprite mode */
110 M = GetMode (A);
111
112 /* Check the height of the bitmap */
113 if (GetBitmapHeight (B) != HEIGHT) {
114 Error ("Invalid bitmap height (%u) for conversion to vic2 sprite",
115 GetBitmapHeight (B));
116 }
117
118 /* If the mode wasn't given, determine it from the image properties */
119 if (M == smAuto) {
120 switch (GetBitmapWidth (B)) {
121 case WIDTH_HR:
122 M = smHighRes;
123 break;
124 case WIDTH_MC:
125 M = smMultiColor;
126 break;
127 default:
128 Error ("Cannot determine mode from image properties");
129 }
130 }
131
132 /* Now check if mode and the image properties match */
133 if (M == smMultiColor) {
134 if (GetBitmapWidth (B) != WIDTH_MC || GetBitmapColors (B) > 4) {
135 Error ("Invalid image properties for multicolor sprite");
136 }
137 } else {
138 if (GetBitmapWidth (B) != WIDTH_HR || GetBitmapColors (B) > 2) {
139 Error ("Invalid image properties for highres sprite");
140 }
141 }
142
143 /* Create the output buffer and resize it to the required size. */
144 D = NewStrBuf ();
145 SB_Realloc (D, 63);
146
147 /* Convert the image */
148 for (Y = 0; Y < HEIGHT; ++Y) {
149 unsigned char V = 0;
150 if (M == smHighRes) {
151 for (X = 0; X < WIDTH_HR; ++X) {
152
153 /* Fetch next bit into byte buffer */
154 V = (V << 1) | (GetPixel (B, X, Y).Index & 0x01);
155
156 /* Store full bytes into the output buffer */
157 if ((X & 0x07) == 0x07) {
158 SB_AppendChar (D, V);
159 V = 0;
160 }
161 }
162 } else {
163 for (X = 0; X < WIDTH_MC; ++X) {
164
165 /* Fetch next bit into byte buffer */
166 V = (V << 2) | (GetPixel (B, X, Y).Index & 0x03);
167
168 /* Store full bytes into the output buffer */
169 if ((X & 0x03) == 0x03) {
170 SB_AppendChar (D, V);
171 V = 0;
172 }
173 }
174 }
175 }
176
177 /* Return the converted bitmap */
178 return D;
179}
180