broke out nether, heightfading, depth, and edgelines from base primitive

overviewer_core/src/primitives/depth.c

@@ -0,0 +1,56 @@
+/* 
+ * 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"
+
+typedef struct {
+    unsigned int min;
+    unsigned int max;
+} PrimitiveDepth;
+
+static int
+depth_start(void *data, RenderState *state, PyObject *support) {
+    PrimitiveDepth *self = (PrimitiveDepth *)data;
+    
+    self->min = 0;
+    if (!render_mode_parse_option(support, "min", "I", &(self->min)))
+        return 1;
+
+    self->max = 127;
+    if (!render_mode_parse_option(support, "max", "I", &(self->max)))
+        return 1;
+
+    return 0;
+}
+
+static int
+depth_hidden(void *data, RenderState *state, int x, int y, int z) {
+    PrimitiveDepth *self = (PrimitiveDepth *)data;
+    if (z > self->max || z < self->min) {
+        return 1;
+    }
+    return 0;
+}
+
+RenderPrimitiveInterface primitive_depth = {
+    "depth", sizeof(PrimitiveDepth),
+    depth_start,
+    NULL,
+    NULL,
+    depth_hidden,
+    NULL,
+};