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Diffstat (limited to 'external/include/stb_rect_pack.h')
| -rw-r--r-- | external/include/stb_rect_pack.h | 583 |
1 files changed, 0 insertions, 583 deletions
diff --git a/external/include/stb_rect_pack.h b/external/include/stb_rect_pack.h deleted file mode 100644 index c75527d..0000000 --- a/external/include/stb_rect_pack.h +++ /dev/null @@ -1,583 +0,0 @@ -// stb_rect_pack.h - v0.10 - public domain - rectangle packing -// Sean Barrett 2014 -// -// Useful for e.g. packing rectangular textures into an atlas. -// Does not do rotation. -// -// Not necessarily the awesomest packing method, but better than -// the totally naive one in stb_truetype (which is primarily what -// this is meant to replace). -// -// Has only had a few tests run, may have issues. -// -// More docs to come. -// -// No memory allocations; uses qsort() and assert() from stdlib. -// Can override those by defining STBRP_SORT and STBRP_ASSERT. -// -// This library currently uses the Skyline Bottom-Left algorithm. -// -// Please note: better rectangle packers are welcome! Please -// implement them to the same API, but with a different init -// function. -// -// Credits -// -// Library -// Sean Barrett -// Minor features -// Martins Mozeiko -// Bugfixes / warning fixes -// Jeremy Jaussaud -// -// Version history: -// -// 0.10 (2016-10-25) remove cast-away-const to avoid warnings -// 0.09 (2016-08-27) fix compiler warnings -// 0.08 (2015-09-13) really fix bug with empty rects (w=0 or h=0) -// 0.07 (2015-09-13) fix bug with empty rects (w=0 or h=0) -// 0.06 (2015-04-15) added STBRP_SORT to allow replacing qsort -// 0.05: added STBRP_ASSERT to allow replacing assert -// 0.04: fixed minor bug in STBRP_LARGE_RECTS support -// 0.01: initial release -// -// LICENSE -// -// This software is dual-licensed to the public domain and under the following -// license: you are granted a perpetual, irrevocable license to copy, modify, -// publish, and distribute this file as you see fit. - -////////////////////////////////////////////////////////////////////////////// -// -// INCLUDE SECTION -// - -#ifndef STB_INCLUDE_STB_RECT_PACK_H -#define STB_INCLUDE_STB_RECT_PACK_H - -#define STB_RECT_PACK_VERSION 1 - -#ifdef STBRP_STATIC -#define STBRP_DEF static -#else -#define STBRP_DEF extern -#endif - -#ifdef __cplusplus -extern "C" { -#endif - -typedef struct stbrp_context stbrp_context; -typedef struct stbrp_node stbrp_node; -typedef struct stbrp_rect stbrp_rect; - -#ifdef STBRP_LARGE_RECTS -typedef int stbrp_coord; -#else -typedef unsigned short stbrp_coord; -#endif - -STBRP_DEF void stbrp_pack_rects (stbrp_context *context, stbrp_rect *rects, int num_rects); -// Assign packed locations to rectangles. The rectangles are of type -// 'stbrp_rect' defined below, stored in the array 'rects', and there -// are 'num_rects' many of them. -// -// Rectangles which are successfully packed have the 'was_packed' flag -// set to a non-zero value and 'x' and 'y' store the minimum location -// on each axis (i.e. bottom-left in cartesian coordinates, top-left -// if you imagine y increasing downwards). Rectangles which do not fit -// have the 'was_packed' flag set to 0. -// -// You should not try to access the 'rects' array from another thread -// while this function is running, as the function temporarily reorders -// the array while it executes. -// -// To pack into another rectangle, you need to call stbrp_init_target -// again. To continue packing into the same rectangle, you can call -// this function again. Calling this multiple times with multiple rect -// arrays will probably produce worse packing results than calling it -// a single time with the full rectangle array, but the option is -// available. - -struct stbrp_rect -{ - // reserved for your use: - int id; - - // input: - stbrp_coord w, h; - - // output: - stbrp_coord x, y; - int was_packed; // non-zero if valid packing - -}; // 16 bytes, nominally - - -STBRP_DEF void stbrp_init_target (stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes); -// Initialize a rectangle packer to: -// pack a rectangle that is 'width' by 'height' in dimensions -// using temporary storage provided by the array 'nodes', which is 'num_nodes' long -// -// You must call this function every time you start packing into a new target. -// -// There is no "shutdown" function. The 'nodes' memory must stay valid for -// the following stbrp_pack_rects() call (or calls), but can be freed after -// the call (or calls) finish. -// -// Note: to guarantee best results, either: -// 1. make sure 'num_nodes' >= 'width' -// or 2. call stbrp_allow_out_of_mem() defined below with 'allow_out_of_mem = 1' -// -// If you don't do either of the above things, widths will be quantized to multiples -// of small integers to guarantee the algorithm doesn't run out of temporary storage. -// -// If you do #2, then the non-quantized algorithm will be used, but the algorithm -// may run out of temporary storage and be unable to pack some rectangles. - -STBRP_DEF void stbrp_setup_allow_out_of_mem (stbrp_context *context, int allow_out_of_mem); -// Optionally call this function after init but before doing any packing to -// change the handling of the out-of-temp-memory scenario, described above. -// If you call init again, this will be reset to the default (false). - - -STBRP_DEF void stbrp_setup_heuristic (stbrp_context *context, int heuristic); -// Optionally select which packing heuristic the library should use. Different -// heuristics will produce better/worse results for different data sets. -// If you call init again, this will be reset to the default. - -enum -{ - STBRP_HEURISTIC_Skyline_default=0, - STBRP_HEURISTIC_Skyline_BL_sortHeight = STBRP_HEURISTIC_Skyline_default, - STBRP_HEURISTIC_Skyline_BF_sortHeight -}; - - -////////////////////////////////////////////////////////////////////////////// -// -// the details of the following structures don't matter to you, but they must -// be visible so you can handle the memory allocations for them - -struct stbrp_node -{ - stbrp_coord x,y; - stbrp_node *next; -}; - -struct stbrp_context -{ - int width; - int height; - int align; - int init_mode; - int heuristic; - int num_nodes; - stbrp_node *active_head; - stbrp_node *free_head; - stbrp_node extra[2]; // we allocate two extra nodes so optimal user-node-count is 'width' not 'width+2' -}; - -#ifdef __cplusplus -} -#endif - -#endif - -////////////////////////////////////////////////////////////////////////////// -// -// IMPLEMENTATION SECTION -// - -#ifdef STB_RECT_PACK_IMPLEMENTATION -#ifndef STBRP_SORT -#include <stdlib.h> -#define STBRP_SORT qsort -#endif - -#ifndef STBRP_ASSERT -#include <assert.h> -#define STBRP_ASSERT assert -#endif - -#ifdef _MSC_VER -#define STBRP__NOTUSED(v) (void)(v) -#else -#define STBRP__NOTUSED(v) (void)sizeof(v) -#endif - -enum -{ - STBRP__INIT_skyline = 1 -}; - -STBRP_DEF void stbrp_setup_heuristic(stbrp_context *context, int heuristic) -{ - switch (context->init_mode) { - case STBRP__INIT_skyline: - STBRP_ASSERT(heuristic == STBRP_HEURISTIC_Skyline_BL_sortHeight || heuristic == STBRP_HEURISTIC_Skyline_BF_sortHeight); - context->heuristic = heuristic; - break; - default: - STBRP_ASSERT(0); - } -} - -STBRP_DEF void stbrp_setup_allow_out_of_mem(stbrp_context *context, int allow_out_of_mem) -{ - if (allow_out_of_mem) - // if it's ok to run out of memory, then don't bother aligning them; - // this gives better packing, but may fail due to OOM (even though - // the rectangles easily fit). @TODO a smarter approach would be to only - // quantize once we've hit OOM, then we could get rid of this parameter. - context->align = 1; - else { - // if it's not ok to run out of memory, then quantize the widths - // so that num_nodes is always enough nodes. - // - // I.e. num_nodes * align >= width - // align >= width / num_nodes - // align = ceil(width/num_nodes) - - context->align = (context->width + context->num_nodes-1) / context->num_nodes; - } -} - -STBRP_DEF void stbrp_init_target(stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes) -{ - int i; -#ifndef STBRP_LARGE_RECTS - STBRP_ASSERT(width <= 0xffff && height <= 0xffff); -#endif - - for (i=0; i < num_nodes-1; ++i) - nodes[i].next = &nodes[i+1]; - nodes[i].next = NULL; - context->init_mode = STBRP__INIT_skyline; - context->heuristic = STBRP_HEURISTIC_Skyline_default; - context->free_head = &nodes[0]; - context->active_head = &context->extra[0]; - context->width = width; - context->height = height; - context->num_nodes = num_nodes; - stbrp_setup_allow_out_of_mem(context, 0); - - // node 0 is the full width, node 1 is the sentinel (lets us not store width explicitly) - context->extra[0].x = 0; - context->extra[0].y = 0; - context->extra[0].next = &context->extra[1]; - context->extra[1].x = (stbrp_coord) width; -#ifdef STBRP_LARGE_RECTS - context->extra[1].y = (1<<30); -#else - context->extra[1].y = 65535; -#endif - context->extra[1].next = NULL; -} - -// find minimum y position if it starts at x1 -static int stbrp__skyline_find_min_y(stbrp_context *c, stbrp_node *first, int x0, int width, int *pwaste) -{ - stbrp_node *node = first; - int x1 = x0 + width; - int min_y, visited_width, waste_area; - - STBRP__NOTUSED(c); - - STBRP_ASSERT(first->x <= x0); - - #if 0 - // skip in case we're past the node - while (node->next->x <= x0) - ++node; - #else - STBRP_ASSERT(node->next->x > x0); // we ended up handling this in the caller for efficiency - #endif - - STBRP_ASSERT(node->x <= x0); - - min_y = 0; - waste_area = 0; - visited_width = 0; - while (node->x < x1) { - if (node->y > min_y) { - // raise min_y higher. - // we've accounted for all waste up to min_y, - // but we'll now add more waste for everything we've visted - waste_area += visited_width * (node->y - min_y); - min_y = node->y; - // the first time through, visited_width might be reduced - if (node->x < x0) - visited_width += node->next->x - x0; - else - visited_width += node->next->x - node->x; - } else { - // add waste area - int under_width = node->next->x - node->x; - if (under_width + visited_width > width) - under_width = width - visited_width; - waste_area += under_width * (min_y - node->y); - visited_width += under_width; - } - node = node->next; - } - - *pwaste = waste_area; - return min_y; -} - -typedef struct -{ - int x,y; - stbrp_node **prev_link; -} stbrp__findresult; - -static stbrp__findresult stbrp__skyline_find_best_pos(stbrp_context *c, int width, int height) -{ - int best_waste = (1<<30), best_x, best_y = (1 << 30); - stbrp__findresult fr; - stbrp_node **prev, *node, *tail, **best = NULL; - - // align to multiple of c->align - width = (width + c->align - 1); - width -= width % c->align; - STBRP_ASSERT(width % c->align == 0); - - node = c->active_head; - prev = &c->active_head; - while (node->x + width <= c->width) { - int y,waste; - y = stbrp__skyline_find_min_y(c, node, node->x, width, &waste); - if (c->heuristic == STBRP_HEURISTIC_Skyline_BL_sortHeight) { // actually just want to test BL - // bottom left - if (y < best_y) { - best_y = y; - best = prev; - } - } else { - // best-fit - if (y + height <= c->height) { - // can only use it if it first vertically - if (y < best_y || (y == best_y && waste < best_waste)) { - best_y = y; - best_waste = waste; - best = prev; - } - } - } - prev = &node->next; - node = node->next; - } - - best_x = (best == NULL) ? 0 : (*best)->x; - - // if doing best-fit (BF), we also have to try aligning right edge to each node position - // - // e.g, if fitting - // - // ____________________ - // |____________________| - // - // into - // - // | | - // | ____________| - // |____________| - // - // then right-aligned reduces waste, but bottom-left BL is always chooses left-aligned - // - // This makes BF take about 2x the time - - if (c->heuristic == STBRP_HEURISTIC_Skyline_BF_sortHeight) { - tail = c->active_head; - node = c->active_head; - prev = &c->active_head; - // find first node that's admissible - while (tail->x < width) - tail = tail->next; - while (tail) { - int xpos = tail->x - width; - int y,waste; - STBRP_ASSERT(xpos >= 0); - // find the left position that matches this - while (node->next->x <= xpos) { - prev = &node->next; - node = node->next; - } - STBRP_ASSERT(node->next->x > xpos && node->x <= xpos); - y = stbrp__skyline_find_min_y(c, node, xpos, width, &waste); - if (y + height < c->height) { - if (y <= best_y) { - if (y < best_y || waste < best_waste || (waste==best_waste && xpos < best_x)) { - best_x = xpos; - STBRP_ASSERT(y <= best_y); - best_y = y; - best_waste = waste; - best = prev; - } - } - } - tail = tail->next; - } - } - - fr.prev_link = best; - fr.x = best_x; - fr.y = best_y; - return fr; -} - -static stbrp__findresult stbrp__skyline_pack_rectangle(stbrp_context *context, int width, int height) -{ - // find best position according to heuristic - stbrp__findresult res = stbrp__skyline_find_best_pos(context, width, height); - stbrp_node *node, *cur; - - // bail if: - // 1. it failed - // 2. the best node doesn't fit (we don't always check this) - // 3. we're out of memory - if (res.prev_link == NULL || res.y + height > context->height || context->free_head == NULL) { - res.prev_link = NULL; - return res; - } - - // on success, create new node - node = context->free_head; - node->x = (stbrp_coord) res.x; - node->y = (stbrp_coord) (res.y + height); - - context->free_head = node->next; - - // insert the new node into the right starting point, and - // let 'cur' point to the remaining nodes needing to be - // stiched back in - - cur = *res.prev_link; - if (cur->x < res.x) { - // preserve the existing one, so start testing with the next one - stbrp_node *next = cur->next; - cur->next = node; - cur = next; - } else { - *res.prev_link = node; - } - - // from here, traverse cur and free the nodes, until we get to one - // that shouldn't be freed - while (cur->next && cur->next->x <= res.x + width) { - stbrp_node *next = cur->next; - // move the current node to the free list - cur->next = context->free_head; - context->free_head = cur; - cur = next; - } - - // stitch the list back in - node->next = cur; - - if (cur->x < res.x + width) - cur->x = (stbrp_coord) (res.x + width); - -#ifdef _DEBUG - cur = context->active_head; - while (cur->x < context->width) { - STBRP_ASSERT(cur->x < cur->next->x); - cur = cur->next; - } - STBRP_ASSERT(cur->next == NULL); - - { - stbrp_node *L1 = NULL, *L2 = NULL; - int count=0; - cur = context->active_head; - while (cur) { - L1 = cur; - cur = cur->next; - ++count; - } - cur = context->free_head; - while (cur) { - L2 = cur; - cur = cur->next; - ++count; - } - STBRP_ASSERT(count == context->num_nodes+2); - } -#endif - - return res; -} - -static int rect_height_compare(const void *a, const void *b) -{ - const stbrp_rect *p = (const stbrp_rect *) a; - const stbrp_rect *q = (const stbrp_rect *) b; - if (p->h > q->h) - return -1; - if (p->h < q->h) - return 1; - return (p->w > q->w) ? -1 : (p->w < q->w); -} - -static int rect_width_compare(const void *a, const void *b) -{ - const stbrp_rect *p = (const stbrp_rect *) a; - const stbrp_rect *q = (const stbrp_rect *) b; - if (p->w > q->w) - return -1; - if (p->w < q->w) - return 1; - return (p->h > q->h) ? -1 : (p->h < q->h); -} - -static int rect_original_order(const void *a, const void *b) -{ - const stbrp_rect *p = (const stbrp_rect *) a; - const stbrp_rect *q = (const stbrp_rect *) b; - return (p->was_packed < q->was_packed) ? -1 : (p->was_packed > q->was_packed); -} - -#ifdef STBRP_LARGE_RECTS -#define STBRP__MAXVAL 0xffffffff -#else -#define STBRP__MAXVAL 0xffff -#endif - -STBRP_DEF void stbrp_pack_rects(stbrp_context *context, stbrp_rect *rects, int num_rects) -{ - int i; - - // we use the 'was_packed' field internally to allow sorting/unsorting - for (i=0; i < num_rects; ++i) { - rects[i].was_packed = i; - #ifndef STBRP_LARGE_RECTS - STBRP_ASSERT(rects[i].w <= 0xffff && rects[i].h <= 0xffff); - #endif - } - - // sort according to heuristic - STBRP_SORT(rects, num_rects, sizeof(rects[0]), rect_height_compare); - - for (i=0; i < num_rects; ++i) { - if (rects[i].w == 0 || rects[i].h == 0) { - rects[i].x = rects[i].y = 0; // empty rect needs no space - } else { - stbrp__findresult fr = stbrp__skyline_pack_rectangle(context, rects[i].w, rects[i].h); - if (fr.prev_link) { - rects[i].x = (stbrp_coord) fr.x; - rects[i].y = (stbrp_coord) fr.y; - } else { - rects[i].x = rects[i].y = STBRP__MAXVAL; - } - } - } - - // unsort - STBRP_SORT(rects, num_rects, sizeof(rects[0]), rect_original_order); - - // set was_packed flags - for (i=0; i < num_rects; ++i) - rects[i].was_packed = !(rects[i].x == STBRP__MAXVAL && rects[i].y == STBRP__MAXVAL); -} -#endif |