polymer: add support for negative lights

And hook them up to cstat 128 (half-submerged, 'c' in mapster).

git-svn-id: https://svn.eduke32.com/eduke32@3092 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/build/include/glbuild.h

@@ -56,6 +56,7 @@ extern void (APIENTRY * bglClear)( GLbitfield mask );
 extern void (APIENTRY * bglColorMask)( GLboolean red, GLboolean green, GLboolean blue, GLboolean alpha );
 extern void (APIENTRY * bglAlphaFunc)( GLenum func, GLclampf ref );
 extern void (APIENTRY * bglBlendFunc)( GLenum sfactor, GLenum dfactor );
+extern void (APIENTRY * bglBlendEquation)( GLenum mode );
 extern void (APIENTRY * bglCullFace)( GLenum mode );
 extern void (APIENTRY * bglFrontFace)( GLenum mode );
 extern void (APIENTRY * bglPolygonOffset)( GLfloat factor, GLfloat units );

polymer/eduke32/build/include/prlights.h

@@ -20,6 +20,7 @@ typedef struct      s_prlight {
     int16_t         tilenum;
     struct          {
         int32_t     emitshadow  : 1;
+        int32_t     negative    : 1;
     }               publicflags;
     // internal members
     float           proj[16];

polymer/eduke32/build/src/engine.c

@@ -9980,6 +9980,9 @@ int32_t loadmaphack(const char *filename)
             scriptfile_getnumber(script, &value);
             light.tilenum = value;
 
+            light.publicflags.emitshadow = 1;
+            light.publicflags.negative = 0;
+
             if (rendmode == 4)
             {
                 if (maphacklightcnt == PR_MAXLIGHTS)

polymer/eduke32/build/src/glbuild.c

@@ -16,6 +16,7 @@ void (APIENTRY *bglClear)(GLbitfield mask);
 void (APIENTRY *bglColorMask)(GLboolean red, GLboolean green, GLboolean blue, GLboolean alpha);
 void (APIENTRY *bglAlphaFunc)(GLenum func, GLclampf ref);
 void (APIENTRY *bglBlendFunc)(GLenum sfactor, GLenum dfactor);
+void (APIENTRY *bglBlendEquation)(GLenum mode);
 void (APIENTRY *bglCullFace)(GLenum mode);
 void (APIENTRY *bglFrontFace)(GLenum mode);
 void (APIENTRY *bglPolygonOffset)(GLfloat factor, GLfloat units);
@@ -495,6 +496,8 @@ int32_t loadglextensions(void)
     if (!hGLDLL) return 0;
 #endif
 
+    bglBlendEquation    = GETPROCEXTSOFT("glBlendEquation");
+
     bglTexImage3D		= GETPROCEXTSOFT("glTexImage3D");
     bglCompressedTexImage2DARB  = GETPROCEXTSOFT("glCompressedTexImage2DARB");
     bglGetCompressedTexImageARB = GETPROCEXTSOFT("glGetCompressedTexImageARB");
@@ -660,6 +663,7 @@ int32_t unloadgldriver(void)
     bglColorMask		= NULL;
     bglAlphaFunc		= NULL;
     bglBlendFunc		= NULL;
+    bglBlendEquation    = NULL;
     bglCullFace		    = NULL;
     bglFrontFace		= NULL;
     bglPolygonOffset	= NULL;

polymer/eduke32/build/src/polymer.c

@@ -4654,11 +4654,13 @@ static int32_t      polymer_bindmaterial(_prmaterial material, int16_t* lights,
     // PR_BIT_LIGHTING_PASS
     if (programbits & prprogrambits[PR_BIT_LIGHTING_PASS].bit)
     {
-	// Careful with that, it works only if we respect the wrapping order
+        bglPushAttrib(GL_COLOR_BUFFER_BIT);
-	// or make sure GL_BLEND is the only ENABLE we mess with here.
+        bglEnable(GL_BLEND);
-        bglPushAttrib(GL_ENABLE_BIT);
-	bglEnable(GL_BLEND);
         bglBlendFunc(GL_ONE, GL_ONE);
+
+        if (prlights[lights[curlight]].publicflags.negative) {
+            bglBlendEquation(GL_FUNC_REVERSE_SUBTRACT);
+        }
     }
 
     // PR_BIT_NORMAL_MAP
@@ -4900,6 +4902,13 @@ static int32_t      polymer_bindmaterial(_prmaterial material, int16_t* lights,
         color[1] = prlights[lights[curlight]].color[1]   / 255.0f;
         color[2] = prlights[lights[curlight]].color[2]   / 255.0f;
 
+        // If this isn't a lighting-only pass, just negate the components
+        if (!curlight && prlights[lights[curlight]].publicflags.negative) {
+            color[0] = -color[0];
+            color[1] = -color[1];
+            color[2] = -color[2];
+        }
+
         bglLightfv(GL_LIGHT0, GL_AMBIENT, pos);
         bglLightfv(GL_LIGHT0, GL_DIFFUSE, color);
         if (material.mdspritespace == GL_TRUE) {
@@ -4933,7 +4942,6 @@ static void         polymer_unbindmaterial(int32_t programbits)
     if (programbits & prprogrambits[PR_BIT_LIGHTING_PASS].bit)
     {
         bglPopAttrib();
-        bglBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
     }
 
     // PR_BIT_NORMAL_MAP

polymer/eduke32/source/actors.c

@@ -740,6 +740,9 @@ void G_AddGameLight(int32_t radius, int32_t srcsprite, int32_t zoffset, int32_t
         mylight.priority = priority;
         mylight.tilenum = 0;
 
+        mylight.publicflags.emitshadow = 1;
+        mylight.publicflags.negative = 0;
+
         actor[srcsprite].lightId = polymer_addlight(&mylight);
         if (actor[srcsprite].lightId >= 0)
             actor[srcsprite].lightptr = &prlights[actor[srcsprite].lightId];
@@ -7752,6 +7755,7 @@ static void G_DoEffectorLights(void)  // STATNUM 14
                     mylight.maxshade = sprite[i].yoffset;
                     mylight.tilenum = 0;
                     mylight.publicflags.emitshadow = 0;
+                    mylight.publicflags.negative = !!(CS & 128);
 
                     if (CS & 2)
                     {
@@ -7788,6 +7792,9 @@ static void G_DoEffectorLights(void)  // STATNUM 14
                     actor[i].lightptr->color[1] = sprite[i].yvel;
                     actor[i].lightptr->color[2] = sprite[i].zvel;
                 }
+                if (!!(CS & 128) != actor[i].lightptr->publicflags.negative) {
+                    actor[i].lightptr->publicflags.negative = !!(CS & 128);
+                }
             }
             break;
         }
@@ -7816,6 +7823,7 @@ static void G_DoEffectorLights(void)  // STATNUM 14
                     mylight.maxshade = sprite[i].yoffset;
                     mylight.tilenum = actor[i].picnum;
                     mylight.publicflags.emitshadow = !(CS & 64);
+                    mylight.publicflags.negative = !!(CS & 128);
 
                     if (CS & 2)
                     {
@@ -7877,6 +7885,9 @@ static void G_DoEffectorLights(void)  // STATNUM 14
                 if (!(CS & 64) != actor[i].lightptr->publicflags.emitshadow) {
                     actor[i].lightptr->publicflags.emitshadow = !(CS & 64);
                 }
+                if (!!(CS & 128) != actor[i].lightptr->publicflags.negative) {
+                    actor[i].lightptr->publicflags.negative = !!(CS & 128);
+                }
                 actor[i].lightptr->tilenum = actor[i].picnum;
             }
 

polymer/eduke32/source/astub.c

@@ -286,6 +286,8 @@ static void addprlight_common1(_prlight *mylightptr, int32_t i)
     else
         mylightptr->priority = PR_LIGHT_PRIO_MAX;
 
+    mylightptr->publicflags.negative = !!(CS & 128);
+
     spritelightid[i] = polymer_addlight(mylightptr);
     if (spritelightid[i] >= 0)
         spritelightptr[i] = &prlights[spritelightid[i]];
@@ -10697,6 +10699,10 @@ void ExtPreCheckKeys(void) // just before drawrooms
                                 }
                                 if (check_prlight_colors(i))
                                     copy_prlight_colors(spritelightptr[i], i);
+                                if (!!(CS & 128) != spritelightptr[i]->publicflags.negative)
+                                {
+                                    spritelightptr[i]->publicflags.negative = !!(CS & 128);
+                                }
                             }
                         }
                     }
@@ -10751,6 +10757,10 @@ void ExtPreCheckKeys(void) // just before drawrooms
                                 {
                                     spritelightptr[i]->publicflags.emitshadow = !(CS & 64);
                                 }
+                                if (!!(CS & 128) != spritelightptr[i]->publicflags.negative)
+                                {
+                                    spritelightptr[i]->publicflags.negative = !!(CS & 128);
+                                }
                                 spritelightptr[i]->tilenum = OW;
                             }
                         }