broke out background-clearing code from base overlay primitive

overviewer_core/rendermodes.py

@@ -146,6 +146,9 @@ class Lighting(RenderPrimitive):
 class SmoothLighting(Lighting):
     name = "smooth-lighting"
 
+class ClearBase(RenderPrimitive):
+    name = "clear-base"
+
 class Overlay(RenderPrimitive):
     name = "overlay"
 

overviewer_core/src/overviewer.h

@@ -26,7 +26,7 @@
 
 // increment this value if you've made a change to the c extesion
 // and want to force users to rebuild
-#define OVERVIEWER_EXTENSION_VERSION 21
+#define OVERVIEWER_EXTENSION_VERSION 22
 
 /* Python PIL, and numpy headers */
 #include <Python.h>

overviewer_core/src/primitives/clear-base.c

@@ -0,0 +1,49 @@
+/* 
+ * This file is part of the Minecraft Overviewer.
+ *
+ * Minecraft Overviewer is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * Minecraft Overviewer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
+ * Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with the Overviewer.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "../overviewer.h"
+
+static int
+clear_base_occluded(void *data, RenderState *state, int x, int y, int z) {
+    if ( (x != 0) && (y != 15) && (z != 127) &&
+         !render_mode_hidden(state->rendermode, x-1, y, z) &&
+         !render_mode_hidden(state->rendermode, x, y, z+1) &&
+         !render_mode_hidden(state->rendermode, x, y+1, z) &&
+         !is_transparent(getArrayByte3D(state->blocks, x-1, y, z)) &&
+         !is_transparent(getArrayByte3D(state->blocks, x, y, z+1)) &&
+         !is_transparent(getArrayByte3D(state->blocks, x, y+1, z))) {
+        return 1;
+    }
+    
+    return 0;
+}
+
+static void
+clear_base_draw(void *data, RenderState *state, PyObject *src, PyObject *mask, PyObject *mask_light) {
+    /* clear the draw space -- set alpha to 0 within mask */
+    tint_with_mask(state->img, 255, 255, 255, 0, mask, state->imgx, state->imgy, 0, 0);
+}
+
+RenderPrimitiveInterface primitive_clear_base = {
+    "clear-base",
+    0,
+    NULL,
+    NULL,
+    clear_base_occluded,
+    NULL,
+    clear_base_draw,
+};

overviewer_core/src/primitives/overlay-mineral.c

@@ -144,7 +144,7 @@ RenderPrimitiveInterface primitive_overlay_mineral = {
     sizeof(RenderPrimitiveMineral),
     overlay_mineral_start,
     overlay_mineral_finish,
-    overlay_occluded,
+    NULL,
     NULL,
     overlay_draw,
 };

overviewer_core/src/primitives/overlay-spawn.c

@@ -102,7 +102,7 @@ RenderPrimitiveInterface primitive_overlay_spawn = {
     sizeof(RenderPrimitiveSpawn),
     overlay_spawn_start,
     overlay_spawn_finish,
-    overlay_occluded,
+    NULL,
     NULL,
     overlay_draw,
 };

overviewer_core/src/primitives/overlay.c

@@ -45,21 +45,6 @@ overlay_finish(void *data, RenderState *state) {
     Py_DECREF(self->white_color);
 }
 
-int
-overlay_occluded(void *data, RenderState *state, int x, int y, int z) {
-    if ( (x != 0) && (y != 15) && (z != 127) &&
-         !render_mode_hidden(state->rendermode, x-1, y, z) &&
-         !render_mode_hidden(state->rendermode, x, y, z+1) &&
-         !render_mode_hidden(state->rendermode, x, y+1, z) &&
-         !is_transparent(getArrayByte3D(state->blocks, x-1, y, z)) &&
-         !is_transparent(getArrayByte3D(state->blocks, x, y, z+1)) &&
-         !is_transparent(getArrayByte3D(state->blocks, x, y+1, z))) {
-        return 1;
-    }
-    
-    return 0;
-}
-
 void
 overlay_draw(void *data, RenderState *state, PyObject *src, PyObject *mask, PyObject *mask_light) {
     RenderPrimitiveOverlay *self = (RenderPrimitiveOverlay *)data;
@@ -72,9 +57,6 @@ overlay_draw(void *data, RenderState *state, PyObject *src, PyObject *mask, PyOb
     else if (state->block == 78) // snow
         increment=9;
     
-    /* clear the draw space -- set alpha to 0 within mask */
-    tint_with_mask(state->img, 255, 255, 255, 0, mask, state->imgx, state->imgy, 0, 0);
-
     /* skip rendering the overlay if we can't see it */
     if (state->z != 127) {
         unsigned char top_block = getArrayByte3D(state->blocks, state->x, state->y, state->z+1);
@@ -112,7 +94,7 @@ RenderPrimitiveInterface primitive_overlay = {
     sizeof(RenderPrimitiveOverlay),
     overlay_start,
     overlay_finish,
-    overlay_occluded,
+    NULL,
     NULL,
     overlay_draw,
 };

overviewer_core/src/primitives/overlay.h

@@ -29,4 +29,3 @@ typedef struct {
 extern RenderPrimitiveInterface primitive_overlay;
 
 void overlay_draw(void *data, RenderState *state, PyObject *src, PyObject *mask, PyObject *mask_light);
-int overlay_occluded(void *data, RenderState *state, int x, int y, int z);