aboutsummaryrefslogtreecommitdiff
path: root/nx-X11/extras/Mesa_6.4.1/progs/xdemos/overlay.c
blob: 4c425b64d463a534cb8998f6affaea13bdc5c6c7 (plain)
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
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
/*
 * GLX overlay test/demo.
 *
 * Brian Paul
 * 18 July 2005
 */

#include <GL/gl.h>
#include <GL/glx.h>
#include <X11/keysym.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>

static int WinWidth = 300, WinHeight = 300;
static Window NormalWindow = 0;
static Window OverlayWindow = 0;
static GLXContext NormalContext = 0;
static GLXContext OverlayContext = 0;
static GLboolean RGBOverlay = GL_FALSE;
static GLfloat Angle = 0.0;


static void
RedrawNormal(Display *dpy)
{
   glXMakeCurrent(dpy, NormalWindow, NormalContext);
   glViewport(0, 0, WinWidth, WinHeight);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
   glMatrixMode(GL_MODELVIEW);
   glClearColor(0.5, 0.5, 0.5, 1.0);
   glClear(GL_COLOR_BUFFER_BIT);
   glColor3f(1.0, 1.0, 0.0);
   glPushMatrix();
   glRotatef(Angle, 0, 0, 1);
   glRectf(-0.8, -0.8, 0.8, 0.8);
   glPopMatrix();
   glXSwapBuffers(dpy, NormalWindow);
}


static void
RedrawOverlay(Display *dpy)
{
   glXMakeCurrent(dpy, OverlayWindow, OverlayContext);
   glViewport(0, 0, WinWidth, WinHeight);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
   glMatrixMode(GL_MODELVIEW);
   glClear(GL_COLOR_BUFFER_BIT);
   if (RGBOverlay) {
      glColor3f(0.0, 1.0, 1.0);
   }
   else {
      glIndexi(2);
   }
   glBegin(GL_LINES);
   glVertex2f(-1, -1);
   glVertex2f(1, 1);
   glVertex2f(1, -1);
   glVertex2f(-1, 1);
   glEnd();
   glXSwapBuffers(dpy, OverlayWindow);
}


static Window
MakeWindow(Display *dpy, XVisualInfo *visinfo, Window parent,
             unsigned int width, unsigned int height)
{
   int scrnum;
   XSetWindowAttributes attr;
   unsigned long mask;
   Window root;
   Window win;

   scrnum = DefaultScreen(dpy);
   root = RootWindow(dpy, scrnum);

   /* window attributes */
   attr.background_pixel = 0;
   attr.border_pixel = 0;
   attr.colormap = XCreateColormap(dpy, root, visinfo->visual, AllocNone);
   attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
   mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;

   win = XCreateWindow(dpy, parent, 0, 0, width, height,
		        0, visinfo->depth, InputOutput,
		        visinfo->visual, mask, &attr);
   return win;
}


static void
MakeNormalWindow(Display *dpy)
{
   int attrib[] = { GLX_RGBA,
		    GLX_RED_SIZE, 1,
		    GLX_GREEN_SIZE, 1,
		    GLX_BLUE_SIZE, 1,
		    GLX_DOUBLEBUFFER,
		    None };
   int scrnum;
   Window root;
   XVisualInfo *visinfo;

   scrnum = DefaultScreen(dpy);
   root = RootWindow(dpy, scrnum);

   visinfo = glXChooseVisual(dpy, scrnum, attrib);
   if (!visinfo) {
      printf("Error: couldn't get an RGB, Double-buffered visual\n");
      exit(1);
   }

   NormalWindow = MakeWindow(dpy, visinfo, root, WinWidth, WinHeight);
   assert(NormalWindow);

   NormalContext = glXCreateContext(dpy, visinfo, NULL, True);
   assert(NormalContext);
}


static void
MakeOverlayWindow(Display *dpy)
{
   int rgbAttribs[] = {
      GLX_RGBA,
      GLX_RED_SIZE, 1,
      GLX_GREEN_SIZE, 1,
      GLX_BLUE_SIZE, 1,
      GLX_DOUBLEBUFFER,
      GLX_LEVEL, 1,
      None
   };
   int indexAttribs[] = {
      /*GLX_RGBA, leave this out */
      GLX_RED_SIZE, 1,
      GLX_GREEN_SIZE, 1,
      GLX_BLUE_SIZE, 1,
      GLX_DOUBLEBUFFER,
      GLX_LEVEL, 1,
      None
   };
   int scrnum;
   Window root;
   XVisualInfo *visinfo;

   scrnum = DefaultScreen(dpy);
   root = RootWindow(dpy, scrnum);

   visinfo = glXChooseVisual(dpy, scrnum, rgbAttribs);
   if (visinfo) {
      printf("Found RGB overlay visual 0x%x\n", (int) visinfo->visualid);
      RGBOverlay = GL_TRUE;
   }
   else {
      visinfo = glXChooseVisual(dpy, scrnum, indexAttribs);
      if (visinfo) {
         printf("Found Color Index overlay visual 0x%x\n",
                (int) visinfo->visualid);
         /* XXX setup the colormap entries! */
      }
      else {
         printf("Error: couldn't get an overlay visual!\n");
         exit(1);
      }
   }

   OverlayWindow = MakeWindow(dpy, visinfo, NormalWindow, WinWidth, WinHeight);
   assert(OverlayWindow);

   OverlayContext = glXCreateContext(dpy, visinfo, NULL, True);
   assert(OverlayContext);
}


static void
EventLoop(Display *dpy)
{
   XEvent event;

   while (1) {
      XNextEvent(dpy, &event);

      switch (event.type) {
	 case Expose:
	    RedrawNormal(dpy);
	    RedrawOverlay(dpy);
	    break;
	 case ConfigureNotify:
            WinWidth = event.xconfigure.width;
            WinHeight = event.xconfigure.height;
            if (event.xconfigure.window == NormalWindow)
               XResizeWindow(dpy, OverlayWindow, WinWidth, WinHeight);
	    break;
         case KeyPress:
            {
               char buffer[10];
               int r, code;
               code = XLookupKeysym(&event.xkey, 0);
	       r = XLookupString(&event.xkey, buffer, sizeof(buffer),
				 NULL, NULL);
	       if (buffer[0] == 27) {
                  /* escape */
                  return;
               }
               else if (buffer[0] == ' ') {
                  Angle += 5.0;
                  RedrawNormal(dpy);
               }
            }
            break;
         default:
            ; /* nothing */
      }
   }
}


int
main(int argc, char *argv[])
{
   Display *dpy = XOpenDisplay(NULL);

   assert(dpy);

   MakeNormalWindow(dpy);
   MakeOverlayWindow(dpy);

   XMapWindow(dpy, NormalWindow);
   XMapWindow(dpy, OverlayWindow);

   EventLoop(dpy);

   glXDestroyContext(dpy, OverlayContext);
   glXDestroyContext(dpy, NormalContext);
   XDestroyWindow(dpy, OverlayWindow);
   XDestroyWindow(dpy, NormalWindow);

   return 0;
}