Inline some functions: about a 5% performance boost.

3 files changed, 137 insertions, 18 deletions

diff --git a/libdimension/dimension/array.h b/libdimension/dimension/array.h
index 036d6c8..5ce6fc3 100644
--- a/libdimension/dimension/array.h
+++ b/libdimension/dimension/array.h
@@ -20,14 +20,16 @@
 
 /*
  * Simple thread-safe generalized arrays, for returning variable-length arrays
- * from functions, and other fun stuff.
+ * from functions, and other fun stuff.  All functions are inline for
+ * performance reasons.
  */
 
 #ifndef DIMENSION_ARRAY_H
 #define DIMENSION_ARRAY_H
 
 #include <pthread.h> /* For pthread_rwlock_t */
-#include <stdlib.h>  /* For size_t */
+#include <stdlib.h>  /* For size_t, malloc */
+#include <string.h>  /* For memcpy */
 
 typedef struct {
   void *ptr;
@@ -36,22 +38,105 @@ typedef struct {
 
 /* Array allocation never returns NULL - if dmnsn_new_array returns, it
    succeeded */
-dmnsn_array *dmnsn_new_array(size_t obj_size);
-void dmnsn_delete_array(dmnsn_array *array);
+DMNSN_INLINE dmnsn_array *
+dmnsn_new_array(size_t obj_size)
+{
+  dmnsn_array *array = (dmnsn_array *)malloc(sizeof(dmnsn_array));
+  if (array) {
+    array->obj_size = obj_size;
+    array->length   = 0;
+    array->capacity = 4; /* Start with capacity of 4 */
+
+    /* Allocate the memory */
+    array->ptr = malloc(array->capacity*array->obj_size);
+    if (!array->ptr) {
+      dmnsn_error(DMNSN_SEVERITY_HIGH, "Array allocation failed.");
+    }
+  }
+
+  return array;
+}
 
-void dmnsn_array_push(dmnsn_array *array, const void *obj);
-void dmnsn_array_pop(dmnsn_array *array, void *obj);
-void dmnsn_array_get(const dmnsn_array *array, size_t i, void *obj);
-void dmnsn_array_set(dmnsn_array *array, size_t i, const void *obj);
-void *dmnsn_array_at(dmnsn_array *array, size_t i);
+/* Delete the array */
+DMNSN_INLINE void
+dmnsn_delete_array(dmnsn_array *array) {
+  if (array) {
+    free(array->ptr);
+    free(array);
+  }
+}
 
-/* Inline so for-loops calling this are fast */
+/* Get the size of the array */
 DMNSN_INLINE size_t
 dmnsn_array_size(const dmnsn_array *array)
 {
   return array->length;
 }
 
-void dmnsn_array_resize(dmnsn_array *array, size_t length);
+/* Set the size of the array */
+DMNSN_INLINE void
+dmnsn_array_resize(dmnsn_array *array, size_t length)
+{
+  if (length > array->capacity) {
+    /* Resize if we don't have enough capacity */
+    array->capacity = length*2; /* We are greedy */
+    array->ptr = realloc(array->ptr, array->obj_size*array->capacity);
+    if (!array->ptr) {
+      dmnsn_error(DMNSN_SEVERITY_HIGH, "Resizing array failed.");
+    }
+  }
+
+  array->length = length;
+}
+
+/* Get the i'th object, bailing out if i is out of range */
+DMNSN_INLINE void
+dmnsn_array_get(const dmnsn_array *array, size_t i, void *obj)
+{
+  if (i >= dmnsn_array_size(array)) {
+    /* Range check failed */
+    dmnsn_error(DMNSN_SEVERITY_HIGH, "Array index out of bounds.");
+  }
+  memcpy(obj, (char *)array->ptr + array->obj_size*i, array->obj_size);
+}
+
+
+/* Set the i'th object, expanding the array if necessary */
+DMNSN_INLINE void
+dmnsn_array_set(dmnsn_array *array, size_t i, const void *obj)
+{
+  if (i >= dmnsn_array_size(array)) {
+    /* Resize if i is out of range */
+    dmnsn_array_resize(array, i + 1);
+  }
+  memcpy((char *)array->ptr + array->obj_size*i, obj, array->obj_size);
+}
+
+/* Element access */
+DMNSN_INLINE void *
+dmnsn_array_at(dmnsn_array *array, size_t i)
+{
+  if (i >= dmnsn_array_size(array)) {
+    /* Resize if i is out of range */
+    dmnsn_array_resize(array, i + 1);
+  }
+  return (char *)array->ptr + array->obj_size*i;
+}
+
+/* Push obj to the end of the array */
+DMNSN_INLINE void
+dmnsn_array_push(dmnsn_array *array, const void *obj)
+{
+  dmnsn_array_set(array, dmnsn_array_size(array), obj);
+}
+
+/* Pop obj from the end of the array */
+DMNSN_INLINE void
+dmnsn_array_pop(dmnsn_array *array, void *obj)
+{
+  size_t size = dmnsn_array_size(array);
+  dmnsn_array_get(array, size - 1, obj); /* Copy the object */
+  dmnsn_array_resize(array, size - 1);   /* Shrink the array */
+}
 
 #endif /* DIMENSION_ARRAY_H */
diff --git a/libdimension/dimension/canvas.h b/libdimension/dimension/canvas.h
index 269763b..4c94c33 100644
--- a/libdimension/dimension/canvas.h
+++ b/libdimension/dimension/canvas.h
@@ -41,11 +41,24 @@ dmnsn_canvas *dmnsn_new_canvas(unsigned int x, unsigned int y);
 void dmnsn_delete_canvas(dmnsn_canvas *canvas);
 
 /* Pixel accessors */
-dmnsn_color dmnsn_get_pixel(const dmnsn_canvas *canvas,
-                            unsigned int x, unsigned int y);
-void dmnsn_set_pixel(dmnsn_canvas *canvas,
-                     unsigned int x, unsigned int y, dmnsn_color color);
-dmnsn_color *dmnsn_pixel_at(dmnsn_canvas *canvas,
-                            unsigned int x, unsigned int y);
+
+DMNSN_INLINE dmnsn_color
+dmnsn_get_pixel(const dmnsn_canvas *canvas, unsigned int x, unsigned int y)
+{
+  return canvas->pixels[y*canvas->x + x];
+}
+
+DMNSN_INLINE void
+dmnsn_set_pixel(dmnsn_canvas *canvas,
+                unsigned int x, unsigned int y, dmnsn_color color)
+{
+  canvas->pixels[y*canvas->x + x] = color;
+}
+
+DMNSN_INLINE dmnsn_color *
+dmnsn_pixel_at(dmnsn_canvas *canvas, unsigned int x, unsigned int y)
+{
+  return canvas->pixels + y*canvas->x + x;
+}
 
 #endif /* DIMENSION_CANVAS_H */
diff --git a/libdimension/dimension/geometry.h b/libdimension/dimension/geometry.h
index 2f08012..9e1aec0 100644
--- a/libdimension/dimension/geometry.h
+++ b/libdimension/dimension/geometry.h
@@ -79,6 +79,7 @@ dmnsn_line_construct(dmnsn_vector x0, dmnsn_vector n)
 DMNSN_INLINE dmnsn_vector
 dmnsn_vector_add(dmnsn_vector lhs, dmnsn_vector rhs)
 {
+  /* 3 additions */
   dmnsn_vector v = { lhs.x + rhs.x, lhs.y + rhs.y, lhs.z + rhs.z };
   return v;
 }
@@ -86,6 +87,7 @@ dmnsn_vector_add(dmnsn_vector lhs, dmnsn_vector rhs)
 DMNSN_INLINE dmnsn_vector
 dmnsn_vector_sub(dmnsn_vector lhs, dmnsn_vector rhs)
 {
+  /* 3 additions */
   dmnsn_vector v = { lhs.x - rhs.x, lhs.y - rhs.y, lhs.z - rhs.z };
   return v;
 }
@@ -93,6 +95,7 @@ dmnsn_vector_sub(dmnsn_vector lhs, dmnsn_vector rhs)
 DMNSN_INLINE dmnsn_vector
 dmnsn_vector_mul(double lhs, dmnsn_vector rhs)
 {
+  /* 3 multiplications */
   dmnsn_vector v = { lhs*rhs.x, lhs*rhs.y, lhs*rhs.z };
   return v;
 }
@@ -100,6 +103,7 @@ dmnsn_vector_mul(double lhs, dmnsn_vector rhs)
 DMNSN_INLINE dmnsn_vector
 dmnsn_vector_div(dmnsn_vector lhs, double rhs)
 {
+  /* 3 divisions */
   dmnsn_vector v = { lhs.x/rhs, lhs.y/rhs, lhs.z/rhs };
   return v;
 }
@@ -107,12 +111,14 @@ dmnsn_vector_div(dmnsn_vector lhs, double rhs)
 DMNSN_INLINE double
 dmnsn_vector_dot(dmnsn_vector lhs, dmnsn_vector rhs)
 {
+  /* 3 multiplications, 2 additions */
   return lhs.x*rhs.x + lhs.y*rhs.y + lhs.z*rhs.z;
 }
 
 DMNSN_INLINE dmnsn_vector
 dmnsn_vector_cross(dmnsn_vector lhs, dmnsn_vector rhs)
 {
+  /* 6 multiplications, 3 additions */
   dmnsn_vector v = { lhs.y*rhs.z - lhs.z*rhs.y,
                      lhs.z*rhs.x - lhs.x*rhs.z,
                      lhs.x*rhs.y - lhs.y*rhs.x };
@@ -122,19 +128,34 @@ dmnsn_vector_cross(dmnsn_vector lhs, dmnsn_vector rhs)
 DMNSN_INLINE double
 dmnsn_vector_norm(dmnsn_vector n)
 {
+  /* 1 sqrt, 3 multiplications, 2 additions */
   return sqrt(dmnsn_vector_dot(n, n));
 }
 
 DMNSN_INLINE dmnsn_vector
 dmnsn_vector_normalize(dmnsn_vector n)
 {
+  /* 1 sqrt, 3 divisions, 3 multiplications, 2 additions */
   return dmnsn_vector_div(n, dmnsn_vector_norm(n));
 }
 
 dmnsn_matrix dmnsn_matrix_inverse(dmnsn_matrix A);
 dmnsn_matrix dmnsn_matrix_mul(dmnsn_matrix lhs, dmnsn_matrix rhs);
 dmnsn_vector dmnsn_matrix_vector_mul(dmnsn_matrix lhs, dmnsn_vector rhs);
-dmnsn_line   dmnsn_matrix_line_mul(dmnsn_matrix lhs, dmnsn_line rhs);
+
+/* Affine line transformation; n = lhs*(x0 + n) - lhs*x0, x0 *= lhs */
+DMNSN_INLINE dmnsn_line
+dmnsn_matrix_line_mul(dmnsn_matrix lhs, dmnsn_line rhs)
+{
+  /* 24 multiplications, 6 divisions, 30 additions */
+  dmnsn_line l;
+  l.x0 = dmnsn_matrix_vector_mul(lhs, rhs.x0);
+  l.n  = dmnsn_vector_sub(
+    dmnsn_matrix_vector_mul(lhs, dmnsn_vector_add(rhs.x0, rhs.n)),
+    l.x0
+  );
+  return l;
+}
 
 /* A point on a line, defined by x0 + t*n */
 DMNSN_INLINE dmnsn_vector