1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
// ____ _ __
// / __ )____ _____ | | / /___ ___________
// / __ / __ \/ ___/ | | /| / / __ `/ ___/ ___/
// / /_/ / /_/ (__ ) | |/ |/ / /_/ / / (__ )
// /_____/\____/____/ |__/|__/\__,_/_/ /____/
//
// A futuristic real-time strategy game.
// This file is part of Bos Wars.
//
/**@name glgraphicdraw.cpp - The general sprite functions. */
//
// (c) Copyright 2000-2008 by Lutz Sammer, Stephan Rasenberg,
// Nehal Mistry, and Jimmy Salmon
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; only version 2 of the License.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
//@{
/*----------------------------------------------------------------------------
-- Includes
----------------------------------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "stratagus.h"
#include "video.h"
/*----------------------------------------------------------------------------
-- Functions
----------------------------------------------------------------------------*/
/** Draw a rectangular part of a CGraphic to the screen.
**
** This function does not attempt to clip the CGraphic based on the
** screen coordinates. If the caller wants clipping, it can set the
** parameters accordingly, or perhaps configure OpenGL to clip the
** output.
**
** @param g
** The graphic to be drawn. It may consist of multiple
** OpenGL textures if it is too large to fit in one texture.
** @param textures
** The OpenGL textures to be drawn. There must be g->NumTextures
** elements in the array. These textures may be the same as
** g->Textures, or perhaps variants of them with different colors
** for a specific player.
** @param gx_beg
** X coordinate of the left side of the rectangle to be drawn from @a *g.
** @param gy_beg
** Y coordinate of the top of the rectangle to be drawn from @a *g.
** @param gx_end
** X coordinate of the right side of the rectangle to be drawn from @a *g.
** @param gy_end
** Y coordinate of the bottom of the rectangle to be drawn from @a *g.
** @param sx_beg
** X coordinate of the left side of the graphic on the screen.
** @param sy_beg
** Y coordinate of the top of the graphic on the screen.
** @param flip
** Whether to flip the graphic in the X direction.
** In any case, the graphic will extend from @a sx_beg
** to (@a gx_end - @a gx_beg + @a sx_beg) on the screen.
** Flipping controls which of those values corresponds
** to @a gx_beg and which one to @a gx_end.
*/
void DrawTexture(const CGraphic *g, GLuint *textures,
int gx_beg, int gy_beg, int gx_end, int gy_end,
int sx_beg, int sy_beg, int flip)
{
// gx and gy coordinates count pixels from the top left corner
// of the CGraphic, which can span multiple textures.
// tx and ty coordinates are in an individual texture,
// as GLfloats between 0.0 and 1.0, like OpenGL requires.
// sx and sy coordinates are on the screen. This function does not
// know what the origin is there.
Assert(0 <= gx_beg);
Assert(0 <= gy_beg);
Assert(gx_beg <= gx_end); // draws nothing if equal
Assert(gy_beg <= gy_end); // draws nothing if equal
Assert(gx_end <= g->GraphicWidth);
Assert(gy_end <= g->GraphicHeight);
for (int tex_gy_beg = gy_beg / GLMaxTextureSize * GLMaxTextureSize;;
tex_gy_beg += GLMaxTextureSize) {
int tex_gy_end = tex_gy_beg + GLMaxTextureSize;
int clip_gy_beg = std::max(gy_beg, tex_gy_beg);
int clip_gy_end = std::min(gy_end, tex_gy_end);
if (clip_gy_beg >= clip_gy_end)
break;
int clip_sy_beg = clip_gy_beg - gy_beg + sy_beg;
int clip_sy_end = clip_gy_end - gy_beg + sy_beg;
Assert(clip_sy_end != clip_sy_beg);
Assert(abs(clip_sy_end - clip_sy_beg) <= g->GraphicHeight);
GLfloat clip_ty_beg, clip_ty_end;
if (tex_gy_end >= g->GraphicHeight) {
// This is the last row of textures in
// the Y direction. These textures may
// be smaller than the ones at the top.
clip_ty_beg = (clip_gy_beg - tex_gy_beg)
* g->TextureHeight
/ (g->GraphicHeight - tex_gy_beg);
clip_ty_end = (clip_gy_end - tex_gy_beg)
* g->TextureHeight
/ (g->GraphicHeight - tex_gy_beg);
} else {
clip_ty_beg = (clip_gy_beg - tex_gy_beg)
/ GLfloat(GLMaxTextureSize);
clip_ty_end = (clip_gy_end - tex_gy_beg)
/ GLfloat(GLMaxTextureSize);
}
Assert(0.0f <= clip_ty_beg);
Assert(clip_ty_beg < clip_ty_end);
Assert(clip_ty_end <= 1.0f);
for (int tex_gx_beg = gx_beg / GLMaxTextureSize
* GLMaxTextureSize;;
tex_gx_beg += GLMaxTextureSize) {
int tex_gx_end = tex_gx_beg + GLMaxTextureSize;
int clip_gx_beg = std::max(gx_beg, tex_gx_beg);
int clip_gx_end = std::min(gx_end, tex_gx_end);
if (clip_gx_beg >= clip_gx_end)
break;
// Flipping does not change which parts of the
// CGraphic get drawn. It only changes where
// they get drawn.
int clip_sx_beg, clip_sx_end;
if (flip) {
clip_sx_beg = sx_beg + (gx_end - clip_gx_beg);
clip_sx_end = sx_beg + (gx_end - clip_gx_end);
} else {
clip_sx_beg = sx_beg + (clip_gx_beg - gx_beg);
clip_sx_end = sx_beg + (clip_gx_end - gx_beg);
}
Assert(clip_sx_end != clip_sx_beg);
Assert(abs(clip_sx_end - clip_sx_beg) <= g->GraphicWidth);
GLfloat clip_tx_beg, clip_tx_end;
if (tex_gx_end >= g->GraphicWidth) {
// This is the last column of textures in
// the X direction. These textures may
// be smaller than the ones at the left.
clip_tx_beg = (clip_gx_beg - tex_gx_beg)
* g->TextureWidth
/ (g->GraphicWidth - tex_gx_beg);
clip_tx_end = (clip_gx_end - tex_gx_beg)
* g->TextureWidth
/ (g->GraphicWidth - tex_gx_beg);
} else {
clip_tx_beg = (clip_gx_beg - tex_gx_beg)
/ GLfloat(GLMaxTextureSize);
clip_tx_end = (clip_gx_end - tex_gx_beg)
/ GLfloat(GLMaxTextureSize);
}
Assert(0.0f <= clip_tx_beg);
Assert(clip_tx_beg < clip_tx_end);
Assert(clip_tx_end <= 1.0f);
int texture = tex_gy_beg / GLMaxTextureSize
* ((g->GraphicWidth - 1) / GLMaxTextureSize + 1)
+ tex_gx_beg / GLMaxTextureSize;
Assert(texture >= 0 && texture < g->NumTextures);
glBindTexture(GL_TEXTURE_2D, textures[texture]);
glBegin(GL_QUADS);
glTexCoord2f(clip_tx_beg, clip_ty_beg);
glVertex2i(clip_sx_beg, clip_sy_beg);
glTexCoord2f(clip_tx_beg, clip_ty_end);
glVertex2i(clip_sx_beg, clip_sy_end);
glTexCoord2f(clip_tx_end, clip_ty_end);
glVertex2i(clip_sx_end, clip_sy_end);
glTexCoord2f(clip_tx_end, clip_ty_beg);
glVertex2i(clip_sx_end, clip_sy_beg);
glEnd();
}
}
}
//@}
|
