more C code fixes. Activated caching.

Also removed some code that I accidentially left in.
Also added a traceback printing decorator around get_chunk() because the
C code can potentially swallow those exceptions.

overviewer_core/src/iterate.c

@@ -99,8 +99,11 @@ PyObject *init_chunk_render(void) {
 /*
  * Returns the requested chunk data from the requested chunk.
  * Returns NULL with an exception set if the requested chunk doesn't exist.
+ * If clearexception is true, clears the exception before returning NULL (for
+ * soft failures)
  */
-PyObject *get_chunk_data(RenderState *state, ChunkNeighborName neighbor, ChunkDataType type) {
+PyObject *get_chunk_data(RenderState *state, ChunkNeighborName neighbor, ChunkDataType type,
+        unsigned char clearexception) {
     int x = state->chunkx;
     int z = state->chunkz;
     PyObject *chunk = NULL;
@@ -127,6 +130,9 @@ PyObject *get_chunk_data(RenderState *state, ChunkNeighborName neighbor, ChunkDa
     if (chunk == NULL) {
         // An exception is already set. RegionSet.get_chunk sets
         // ChunkDoesntExist
+        if (clearexception) {
+            PyErr_Clear();
+        }
         return NULL;
     }
     
@@ -439,28 +445,25 @@ chunk_render(PyObject *self, PyObject *args) {
     Py_DECREF(imgsize1_py);
 
     /* get the block data directly from numpy: */
-    blocks_py = get_chunk_data(&state, CURRENT, BLOCKS);
+    blocks_py = get_chunk_data(&state, CURRENT, BLOCKS, 0);
     state.blocks = blocks_py;
     if (blocks_py == NULL) {
         return NULL;
     }
     
-    state.blockdatas = get_chunk_data(&state, CURRENT, BLOCKDATA);
+    state.blockdatas = get_chunk_data(&state, CURRENT, BLOCKDATA, 1);
 
-    left_blocks_py = get_chunk_data(&state, DOWN_LEFT, BLOCKS);
+    left_blocks_py = get_chunk_data(&state, DOWN_LEFT, BLOCKS, 1);
     state.left_blocks = left_blocks_py;
 
-    right_blocks_py = get_chunk_data(&state, DOWN_RIGHT, BLOCKS);
+    right_blocks_py = get_chunk_data(&state, DOWN_RIGHT, BLOCKS, 1);
     state.right_blocks = right_blocks_py;
 
-    up_left_blocks_py = get_chunk_data(&state, UP_LEFT, BLOCKS);
+    up_left_blocks_py = get_chunk_data(&state, UP_LEFT, BLOCKS, 1);
     state.up_left_blocks = up_left_blocks_py;
 
-    up_right_blocks_py = get_chunk_data(&state, UP_RIGHT, BLOCKS);
+    up_right_blocks_py = get_chunk_data(&state, UP_RIGHT, BLOCKS, 1);
     state.up_right_blocks = up_right_blocks_py;
-
-    // Clear any error that was set by the above calls
-    PyErr_Clear();
     
     /* set up the random number generator again for each chunk
        so tallgrass is in the same place, no matter what mode is used */

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 15
+#define OVERVIEWER_EXTENSION_VERSION 16
 
 /* Python PIL, and numpy headers */
 #include <Python.h>
@@ -137,7 +137,8 @@ typedef enum
     UP_RIGHT,   /* +1,  0 */
     UP_LEFT,    /*  0, -1 */
 } ChunkNeighborName;
-PyObject *get_chunk_data(RenderState *state, ChunkNeighborName neighbor, ChunkDataType type);
+PyObject *get_chunk_data(RenderState *state, ChunkNeighborName neighbor, ChunkDataType type,
+        unsigned char clearexception);
 
 /* pull in the rendermode info */
 #include "rendermodes.h"

overviewer_core/src/primitives/cave.c

@@ -214,21 +214,19 @@ cave_start(void *data, RenderState *state, PyObject *support) {
         return 1;
     
     /* if there's skylight we are in the surface! */
-    self->skylight = get_chunk_data(state, CURRENT, SKYLIGHT);
-    self->left_skylight = get_chunk_data(state, DOWN_LEFT, SKYLIGHT);
-    self->right_skylight = get_chunk_data(state, DOWN_RIGHT, SKYLIGHT);
-    self->up_left_skylight = get_chunk_data(state, UP_LEFT, SKYLIGHT);
-    self->up_right_skylight = get_chunk_data(state, UP_RIGHT, SKYLIGHT);
+    self->skylight = get_chunk_data(state, CURRENT, SKYLIGHT, 1);
+    self->left_skylight = get_chunk_data(state, DOWN_LEFT, SKYLIGHT, 1);
+    self->right_skylight = get_chunk_data(state, DOWN_RIGHT, SKYLIGHT, 1);
+    self->up_left_skylight = get_chunk_data(state, UP_LEFT, SKYLIGHT, 1);
+    self->up_right_skylight = get_chunk_data(state, UP_RIGHT, SKYLIGHT, 1);
     
     if (self->only_lit) {
-        self->blocklight = get_chunk_data(state, CURRENT, BLOCKLIGHT);
-        self->left_blocklight = get_chunk_data(state, DOWN_LEFT, BLOCKLIGHT);
-        self->right_blocklight = get_chunk_data(state, DOWN_RIGHT, BLOCKLIGHT);
-        self->up_left_blocklight = get_chunk_data(state, UP_LEFT, BLOCKLIGHT);
-        self->up_right_blocklight = get_chunk_data(state, UP_RIGHT, BLOCKLIGHT);
+        self->blocklight = get_chunk_data(state, CURRENT, BLOCKLIGHT, 1);
+        self->left_blocklight = get_chunk_data(state, DOWN_LEFT, BLOCKLIGHT, 1);
+        self->right_blocklight = get_chunk_data(state, DOWN_RIGHT, BLOCKLIGHT, 1);
+        self->up_left_blocklight = get_chunk_data(state, UP_LEFT, BLOCKLIGHT, 1);
+        self->up_right_blocklight = get_chunk_data(state, UP_RIGHT, BLOCKLIGHT, 1);
     }
-    // Non-existant neighboring blocks is not an error
-    PyErr_Clear();
 
     return 0;
 }

overviewer_core/src/primitives/lighting.c

@@ -359,20 +359,17 @@ lighting_start(void *data, RenderState *state, PyObject *support) {
     self->facemasks[1] = PyTuple_GetItem(self->facemasks_py, 1);
     self->facemasks[2] = PyTuple_GetItem(self->facemasks_py, 2);
     
-    self->skylight = get_chunk_data(state, CURRENT, SKYLIGHT);
-    self->blocklight = get_chunk_data(state, CURRENT, BLOCKLIGHT);
-    self->left_skylight = get_chunk_data(state, DOWN_LEFT, SKYLIGHT);
-    self->left_blocklight = get_chunk_data(state, DOWN_LEFT, BLOCKLIGHT);
-    self->right_skylight = get_chunk_data(state, DOWN_RIGHT, SKYLIGHT);
-    self->right_blocklight = get_chunk_data(state, DOWN_RIGHT, BLOCKLIGHT);
-    self->up_left_skylight = get_chunk_data(state, UP_LEFT, SKYLIGHT);
-    self->up_left_blocklight = get_chunk_data(state, UP_LEFT, BLOCKLIGHT);
-    self->up_right_skylight = get_chunk_data(state, UP_RIGHT, SKYLIGHT);
-    self->up_right_blocklight = get_chunk_data(state, UP_RIGHT, BLOCKLIGHT);
+    self->skylight = get_chunk_data(state, CURRENT, SKYLIGHT, 1);
+    self->blocklight = get_chunk_data(state, CURRENT, BLOCKLIGHT, 1);
+    self->left_skylight = get_chunk_data(state, DOWN_LEFT, SKYLIGHT, 1);
+    self->left_blocklight = get_chunk_data(state, DOWN_LEFT, BLOCKLIGHT, 1);
+    self->right_skylight = get_chunk_data(state, DOWN_RIGHT, SKYLIGHT, 1);
+    self->right_blocklight = get_chunk_data(state, DOWN_RIGHT, BLOCKLIGHT, 1);
+    self->up_left_skylight = get_chunk_data(state, UP_LEFT, SKYLIGHT, 1);
+    self->up_left_blocklight = get_chunk_data(state, UP_LEFT, BLOCKLIGHT, 1);
+    self->up_right_skylight = get_chunk_data(state, UP_RIGHT, SKYLIGHT, 1);
+    self->up_right_blocklight = get_chunk_data(state, UP_RIGHT, BLOCKLIGHT, 1);
 
-    // Non-existant neighbor block is not an error
-    PyErr_Clear();
-    
     if (self->night) {
         self->calculate_light_color = calculate_light_color_night;
     } else {

overviewer_core/src/rendermode-spawn.c

@@ -69,8 +69,8 @@ rendermode_spawn_start(void *data, RenderState *state, PyObject *options) {
     
     /* now do custom initializations */
     self = (RenderModeSpawn *)data;
-    self->blocklight = get_chunk_data(state, CURRENT, BLOCKLIGHT);
-    self->skylight = get_chunk_data(state, CURRENT, SKYLIGHT);
+    self->blocklight = get_chunk_data(state, CURRENT, BLOCKLIGHT, 1);
+    self->skylight = get_chunk_data(state, CURRENT, SKYLIGHT, 1);
     
     /* setup custom color */
     self->parent.get_color = get_color;