X-Git-Url: https://sfsrealm.hopto.org/projects/gitweb.cgi?a=blobdiff_plain;f=grpapi%2Fgrpapi.h;h=8a61f43215ba0cfcd26dcfed8b5677eebc6977c7;hb=afcd1861b390cdcd023cf6e7dfe28c44ba6e2cca;hp=2f48cef5fe531129d1a228cd7f18bf19664bd661;hpb=ecca31ff6c588a09592e9a0ca08180828ab8a5a7;p=grpapi.git

diff --git a/grpapi/grpapi.h b/grpapi/grpapi.h
index 2f48cef..8a61f43 100644
--- a/grpapi/grpapi.h
+++ b/grpapi/grpapi.h
@@ -39,12 +39,20 @@ typedef struct {
                                    // the shadow's color, third byte is green,
                                    // fourth byte is blue; like this:
                                    // SHADOW_COLOR|0xBBGGRR00
+                                   // This can be accomplished by using the left shift
+                                   // operator like this:  SHADOW_COLOR|(color << 8)
 #define ALPHA_BLEND     0x00000008 // Blends the graphic with what it is being drawn over.
                                    // The dwAlpha parameter will only be used when this
                                    // flag is specified.  dwAlpha is an RGB value
                                    // (0xBBGGRR).
                                    // Note: Because of the extra calculations required,
                                    // alpha blended graphics take longer to draw
+#define USE_INDEX       0x00000010 // Only valid when used with a custom SetPixel function.
+                                   // This flag cannot be used in combination with
+                                   // ALPHA_BLEND or SHADOW_COLOR
+                                   // When this flag is used, the index to a color in the
+                                   // palette will be passed to your custom SetPixel
+                                   // function instead of the actual color.
 
 // Palette is an array of 256 DWORD's
 // For LoadPalette and LoadGrp, lpFileName may be a file in an open mpq archive
@@ -73,7 +81,7 @@ typedef void (WINAPI* SETPIXELPROC)(
 
 // Call these to have DrawGrp use custom functions for reading and drawing pixels
 // so that you can have it read from and write to a buffer, for example.
-void GRPAPI WINAPI SetFunctionGetPixel(GETPIXELPROC lpGetPixelProc);
+void GRPAPI WINAPI SetFunctionGetPixel(GETPIXELPROC lpGetPixelProc); // Only used with ALPHA_BLEND
 void GRPAPI WINAPI SetFunctionSetPixel(SETPIXELPROC lpSetPixelProc);
 
 // Call this to make a different Storm.dll-compatible MPQ library be used (like SFMPQ).