mod_q3shader_force_addalpha (default 0)

treat GL_ONE GL_ONE (or add) blendfunc as GL_SRC_ALPHA GL_ONE for compatibility with older DarkPlaces releases

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11329 d7cf8633-e32d-0410-b094-e92efae38249
::stable-branch::merge=f21f81fa1c3b997ef5621380a7c98a6ecee7458e

diff --git a/model_brush.c b/model_brush.c
index cb830aaf59261cc89552cfd37fa336fb9554548b..470b8586b0cbd5a5180a3da948bcb3e30313a5d7 100644 (file)
--- a/model_brush.c
+++ b/model_brush.c
@@ -53,6 +53,7 @@ cvar_t mod_q3shader_default_offsetmapping_scale = {CVAR_SAVE, "mod_q3shader_defa
 cvar_t mod_q3shader_default_offsetmapping_bias = {CVAR_SAVE, "mod_q3shader_default_offsetmapping_bias", "0", "default bias used for offsetmapping"};
 cvar_t mod_q3shader_default_polygonfactor = {0, "mod_q3shader_default_polygonfactor", "0", "biases depth values of 'polygonoffset' shaders to prevent z-fighting artifacts"};
 cvar_t mod_q3shader_default_polygonoffset = {0, "mod_q3shader_default_polygonoffset", "-2", "biases depth values of 'polygonoffset' shaders to prevent z-fighting artifacts"};
+cvar_t mod_q3shader_force_addalpha = {0, "mod_q3shader_force_addalpha", "0", "treat GL_ONE GL_ONE (or add) blendfunc as GL_SRC_ALPHA GL_ONE for compatibility with older DarkPlaces releases"};
 cvar_t mod_q1bsp_polygoncollisions = {0, "mod_q1bsp_polygoncollisions", "0", "disables use of precomputed cliphulls and instead collides with polygons (uses Bounding Interval Hierarchy optimizations)"};
 cvar_t mod_collision_bih = {0, "mod_collision_bih", "1", "enables use of generated Bounding Interval Hierarchy tree instead of compiled bsp tree in collision code"};
 cvar_t mod_recalculatenodeboxes = {0, "mod_recalculatenodeboxes", "1", "enables use of generated node bounding boxes based on BSP tree portal reconstruction, rather than the node boxes supplied by the map compiler"};
@@ -92,10 +93,16 @@ void Mod_BrushInit(void)
        Cvar_RegisterVariable(&mod_q3shader_default_offsetmapping_bias);
        Cvar_RegisterVariable(&mod_q3shader_default_polygonfactor);
        Cvar_RegisterVariable(&mod_q3shader_default_polygonoffset);
+       Cvar_RegisterVariable(&mod_q3shader_force_addalpha);
        Cvar_RegisterVariable(&mod_q1bsp_polygoncollisions);
        Cvar_RegisterVariable(&mod_collision_bih);
        Cvar_RegisterVariable(&mod_recalculatenodeboxes);
 
+       // these games were made for older DP engines and are no longer
+       // maintained; use this hack to show their textures properly
+       if(gamemode == GAME_NEXUIZ)
+               Cvar_SetQuick(&mod_q3shader_force_addalpha, "1");
+
        memset(&mod_q1bsp_texture_solid, 0, sizeof(mod_q1bsp_texture_solid));
        strlcpy(mod_q1bsp_texture_solid.name, "solid" , sizeof(mod_q1bsp_texture_solid.name));
        mod_q1bsp_texture_solid.surfaceflags = 0;

diff --git a/model_shared.c b/model_shared.c
index a524191309dafbc11cf8d0b94091b0f6850f97b4..9c5ca20392571c353f06133922d3735ac7c43b1b 100644 (file)
--- a/model_shared.c
+++ b/model_shared.c
@@ -1627,6 +1627,7 @@ extern cvar_t mod_q3shader_default_offsetmapping_scale;
 extern cvar_t mod_q3shader_default_offsetmapping_bias;
 extern cvar_t mod_q3shader_default_polygonoffset;
 extern cvar_t mod_q3shader_default_polygonfactor;
+extern cvar_t mod_q3shader_force_addalpha;
 void Mod_LoadQ3Shaders(void)
 {
        int j;
@@ -1970,6 +1971,15 @@ void Mod_LoadQ3Shaders(void)
                                                        shader.textureblendalpha = true;
                                                }
                                        }
+
+                                       if(mod_q3shader_force_addalpha.integer)
+                                       {
+                                               // for a long while, DP treated GL_ONE GL_ONE as GL_SRC_ALPHA GL_ONE
+                                               // this cvar brings back this behaviour
+                                               if(layer->blendfunc[0] == GL_ONE && layer->blendfunc[1] == GL_ONE)
+                                                       layer->blendfunc[0] = GL_SRC_ALPHA;
+                                       }
+
                                        layer->texflags = 0;
                                        if (layer->alphatest)
                                                layer->texflags |= TEXF_ALPHA;
@@ -1987,7 +1997,6 @@ void Mod_LoadQ3Shaders(void)
                                                        layer->texflags |= TEXF_ALPHA;
                                                        break;
                                        }
-
                                        if (!(shader.surfaceparms & Q3SURFACEPARM_NOMIPMAPS))
                                                layer->texflags |= TEXF_MIPMAP;
                                        if (!(shader.textureflags & Q3TEXTUREFLAG_NOPICMIP))