MyLine Command (A Complete Example)

We have finally reached the point where we can produce an entire example.   In my previous post I explained how, conceptually, this command will work.  Now, here is the actual code for the command along with a lot of comments.

I have also copied and commented out the definitions for the relevant elements that we are going to create.

I hope that you fire up Visual Studio and try building this code; if you are impatient though and want to just run it, here is the dll.

Code Snippet - MyLine Command (A Complete Example)

1. ////////////////////////////////////////////////////////////////////////////
2. //
3. //    Written by: L. Lee Saunders
4. //    Date: 8/15/2010
5. //    (C)2010 BeerAndPretzelGames.com
6. //    All rights reserved
7. //
8. ////////////////////////////////////////////////////////////////////////////
9. #include <windows.h>
10.  
11. extern "C"
12. {  
13.     #include <XP.H>
14.     #include <Extend/Mysvc.h>
15. }
16.  
17. #define XPID 0xF000
18.  
19. void XPCALL About(void);
20. void XPCALL MYLINE(void);
21.  
22. char CList[]="MYLINE\0";
23. PCMDPROC PList[]={About,MYLINE};
24.  
25. XP MyXP =
26.    { 0, CList, PList, 0, 0, 0, XPID, 0, 500, 0, 0, 500 };
27. ////////////////////////////////////////////////////////////////////////////
28.  
29.  
30. ////////////////////////////////////////////////////////////////////////////
31. FORMST(MyAPkt,"BLOG DLL commands:\n\n"
32.        "\tMYLINE - Duplicating the Line Command #s\n\0")
33.  
34. void XPCALL About (void)
35. {
36.     FormSt(&MyAPkt,RSC(FD_MsgBox));
37. }
38. ////////////////////////////////////////////////////////////////////////////
39.  
40.  
41. ////////////////////////////////////////////////////////////////////////////
42. void XPCALL MYLINE2 (int Result,int Result2,int Result3);
43. void XPCALL MYLINE3 (int Result,int Result2,int Result3);
44.  
45. //This is the definition of LINE2
46. //==========================================================================
47. //typedef struct
48. //{
49. //    CSTUFF    CStuff;              // entity properties
50. //    GLINE2    Line;                // line properties
51. //} LINE2;
52.  
53. //This is the definition of GLINE2
54. //==========================================================================
55. //typedef struct
56. //{
57. //    GPOINT2 p1;                    // starting point
58. //    GPOINT2 p2;                    // ending point
59. //} GLINE2;
60.  
61. //This is the definition of GPOINT2
62. //==========================================================================
63. //typedef struct
64. //{
65. //    float x;
66. //    float y;
67. //} GPOINT2;
68.  
69. //This is the definition of CSTUFF
70. //==========================================================================
71. //typedef struct
72. //{
73. //    int    ERLen;                    // entity record length
74. //    unsigned char    EType;          // entity type code
75. //    char    EFlags;                  // erase/select bits
76. //    char    EFlags2;                 // extra flags
77. //    unsigned char    EColor;         // entity color
78. //    unsigned char    EColor2;        // fill (2nd) color
79. //    char    EThick;                  // pen thickness 0..25.4 mm
80. //    short    WPlane;                 // workplane (0 = XY plane)
81. //    short    ELayer;                 // layer
82. //    short    ELStyle;                // line style (0=solid)
83. //    short    GroupID;                // group id (0 = not grouped)
84. //    short    EFStyle;                // fill style (0=hollow)
85. //    float    LWidth;                 // line width
86. //    int    Tag;                      // entity tag id
87. //} CSTUFF;
88.  
89. //This is the working structure that we will use to create all the lines
90. LINE2 BuildL = {
91.     sizeof(LINE2),                // entity record length
92.     ET_LINE2,                     // entity type code
93.     0,                            // erase/select bits
94.     0,                            // extra flags
95.     1,                            // entity color
96.     1,                            // fill (2nd) color
97.     0,                            // pen thickness 0..25.4 mm
98.     0,                            // workplane (0 = XY plane)
99.     1,                            // layer
100.     0,                            // line style (0=solid)
101.     0,                            // group id (0 = not grouped)
102.     0,                            // fill style (0=hollow)
103.     0.0,                          // line width
104.     0,                            // entity tag id
105.     0.0,                          // starting point: x
106.     0.0,                          // starting point: y
107.     1.0,                          // ending point: x
108.     1.0                           // ending point: y
109. };
110.  
111. FORMST(lpszFirstPoint,"1st point:\0")
112.  
113. FORMST(lpszNextPoint,"Next point:\0")
114.  
115. RDATA P1Req =
116.    { sizeof(RDATA), RD_2DC, NULL, RDF_C, (DWORD*)&BuildL.Line.p1,
117.     (DWORD*)&lpszFirstPoint, RDC_XH, MYLINE2, NULL, NULL, 0, NULL, 0};
118.  
119. RDATA P2Req =
120.    { sizeof(RDATA), RD_2DC, NULL, RDF_C, (DWORD*)&BuildL.Line.p2,
121.     (DWORD*)&lpszNextPoint, RDC_RBAND, MYLINE3, NULL, NULL, 0, NULL, 0};
122.  
123. ////////////////////////////////////////////////////////////////////////////
124.  
125.  
126. ////////////////////////////////////////////////////////////////////////////
127. void XPCALL MYLINE (void)
128. {
129.     ReqData(&P1Req);  //get first point
130. }
131. ////////////////////////////////////////////////////////////////////////////
132.  
133.  
134. ////////////////////////////////////////////////////////////////////////////
135. void XPCALL MYLINE2 (int Result,int Result2,int Result3)
136. {
137.     if (Result != X_OK) { CmdEnd(); return; } //If we did not get valid info
138.     
139.     MarkUndoAdd();  //Enable Undo
140.     NewCsrOrg(BuildL.Line.p1.x, BuildL.Line.p1.y);  //Set cursor origin
141.     ReqData(&P2Req);  //Get next point
142. }
143. ////////////////////////////////////////////////////////////////////////////
144.  
145.  
146. ////////////////////////////////////////////////////////////////////////////
147. void XPCALL MYLINE3 (int Result,int Result2,int Result3)
148. {
149.     pENTREC pEntRec;  //Create a new drawing database entity
150.  
151.     if (Result != X_OK) { CmdEnd(); return; } //If we did not get valid info
152.  
153.     //This gets all the current stuff like current color and assigns it
154.     //to our line entity.
155.     GetCStuff(&BuildL.CStuff);
156.  
157.     //Append a copy of our line to the DB and return a pointer to the new
158.     //entity in the database.  We assign it to pEntRec.
159.     pEntRec=DLApnd(NULL,(pENTREC)&BuildL);
160.     
161.     EDraw(pEntRec);  //Draw our line
162.     ShowChanges(); //Needed for CC3 to "Show Changes" to the DB
163.  
164.     BuildL.Line.p1.x=BuildL.Line.p2.x;  //move 2nd x to 1st x
165.     BuildL.Line.p1.y=BuildL.Line.p2.y;  //move 2nd y to 1st y
166.     
167.     NewCsrOrg(BuildL.Line.p1.x,BuildL.Line.p1.y);  //Set cursor origin
168.  
169.     ReqData(&P2Req);  //Get next point
170. }
171. ////////////////////////////////////////////////////////////////////////////
172.  
173.  
174. ////////////////// DllMain - XP initialization & Unload code ///////////
175. BOOL WINAPI DllMain (HINSTANCE hDLL, DWORD dwReason, LPVOID lpReserved)
176. {
177.     switch (dwReason)
178.     {
179.         case DLL_PROCESS_ATTACH:
180.         {
181.             MyXP.ModHdl=hDLL;
182.             XPRegCmd(&MyXP);
183.             break;
184.         }
185.         case DLL_PROCESS_DETACH:
186.         {
187.             XPUnregCmd(&MyXP);
188.             break;
189.         }
190.     }
191.     return TRUE;
192. }
193. ////////////////////////////////////////////////////////////////////////////