polygon intersector improvements
[swftools.git] / lib / gfxpoly / renderpoly.c
diff --git a/lib/gfxpoly/renderpoly.c b/lib/gfxpoly/renderpoly.c
new file mode 100644 (file)
index 0000000..de7dc0a
--- /dev/null
@@ -0,0 +1,292 @@
+#include <stdlib.h>
+#include <memory.h>
+#include <math.h>
+#include "renderpoly.h"
+
+typedef struct _renderpoint
+{
+    double x;
+    segment_dir_t dir;
+    fillstyle_t*fs;
+} renderpoint_t;
+
+typedef struct _renderline
+{
+    renderpoint_t*points;
+    int size;
+    int num;
+} renderline_t;
+
+typedef struct _renderbuf
+{
+    intbbox_t bbox;
+    int width;
+    int height;
+    double zoom;
+    renderline_t*lines;
+} renderbuf_t;
+
+static inline void add_pixel(renderbuf_t*buf, double x, int y, segment_dir_t dir, fillstyle_t*fs)
+{
+    renderpoint_t p;
+    p.x = x;
+    p.dir = dir;
+    p.fs = fs;
+
+    if(x >= buf->bbox.xmax || y >= buf->bbox.ymax || y < buf->bbox.ymin) 
+        return;
+    renderline_t*l = &buf->lines[y-buf->bbox.ymin];
+
+    if(l->num == l->size) {
+       l->size += 32;
+       l->points = (renderpoint_t*)rfx_realloc(l->points, l->size * sizeof(renderpoint_t));
+    }
+    l->points[l->num] = p;
+    l->num++;
+}
+#define CUT 0.5
+#define INT(x) ((int)((x)+16)-16)
+static void add_line(renderbuf_t*buf, double x1, double y1, double x2, double y2, fillstyle_t*fs)
+{
+    x1 *= buf->zoom;
+    y1 *= buf->zoom;
+    x2 *= buf->zoom;
+    y2 *= buf->zoom;
+    double diffx, diffy;
+    double ny1, ny2, stepx;
+    segment_dir_t dir = DIR_DOWN;
+    if(y2 < y1) {
+        dir = DIR_UP;
+        double x,y;
+       x = x1;x1 = x2;x2=x;
+       y = y1;y1 = y2;y2=y;
+    }
+    diffx = x2 - x1;
+    diffy = y2 - y1;
+    ny1 = INT(y1)+CUT;
+    ny2 = INT(y2)+CUT;
+
+    if(ny1 < y1) {
+        ny1 = INT(y1) + 1.0 + CUT;
+    }
+    if(ny2 >= y2) {
+        ny2 = INT(y2) - 1.0 + CUT;
+    }
+    if(ny1 > ny2)
+        return;
+
+    stepx = diffx/diffy;
+    x1 = x1 + (ny1-y1)*stepx;
+    x2 = x2 + (ny2-y2)*stepx;
+
+    int posy=INT(ny1);
+    int endy=INT(ny2);
+    double posx=0;
+    double startx = x1;
+
+    while(posy<=endy) {
+        double xx = startx + posx;
+        add_pixel(buf, xx, posy, dir, fs);
+        posx+=stepx;
+        posy++;
+    }
+}
+
+static int compare_renderpoints(const void * _a, const void * _b)
+{
+    renderpoint_t*a = (renderpoint_t*)_a;
+    renderpoint_t*b = (renderpoint_t*)_b;
+    if(a->x < b->x) return -1;
+    if(a->x > b->x) return 1;
+    return 0;
+}
+
+static void fill_bitwise(unsigned char*line, int x1, int x2)
+{
+    int p1 = x1>>3;
+    int p2 = x2>>3;
+    int b1 = 0xff >> (x1&7);
+    int b2 = 0xff << (1+7-(x2&7));
+    if(p1==p2) {
+        line[p1] |= b1&b2;
+    } else {
+        line[p1] |= b1;
+        memset(&line[p1+1], 255, p2-(p1+1));
+        line[p2] = b2;
+    }
+}
+
+unsigned char* render_polygon(gfxpoly_t*polygon, intbbox_t*bbox, double zoom, windrule_t*rule)
+{
+    renderbuf_t _buf, *buf=&_buf;
+    buf->width = (bbox->xmax - bbox->xmin);
+    buf->height = (bbox->ymax - bbox->ymin);
+    buf->bbox = *bbox;
+    buf->zoom = zoom;
+    int width8 = (buf->width+7) >> 3;
+    unsigned char* image = (unsigned char*)malloc(width8*buf->height);
+    memset(image, 0, width8*buf->height);
+    
+    buf->lines = (renderline_t*)rfx_alloc(buf->height*sizeof(renderline_t));
+    int y;
+    for(y=0;y<buf->height;y++) {
+       memset(&buf->lines[y], 0, sizeof(renderline_t));
+        buf->lines[y].points = 0;
+        buf->lines[y].num = 0;
+    }
+
+    edge_t*e;
+    for(e=polygon;e;e=e->next) {
+        add_line(buf, e->a.x, e->a.y, e->b.x, e->b.y, e->style);
+    }
+
+    for(y=0;y<buf->height;y++) {
+       renderpoint_t*points = buf->lines[y].points;
+        unsigned char*line = &image[width8*y];
+       int n;
+       int num = buf->lines[y].num;
+        qsort(points, num, sizeof(renderpoint_t), compare_renderpoints);
+        int lastx = 0;
+
+        windstate_t*fill = 0;
+        for(n=0;n<num;n++) {
+            renderpoint_t*p = &points[n];
+            int x = (int)(p->x - bbox->xmin);
+            
+            if(x < lastx)
+                x = lastx;
+            if(x > buf->width) {
+                break;
+            }
+            if(fill->is_filled && x!=lastx) {
+                fill_bitwise(line, lastx, x);
+            }
+            fill = rule->add(fill, p->fs, p->dir, polygon);
+            lastx = x;
+        }
+        if(fill->is_filled && lastx!=buf->width)
+            fill_bitwise(line, lastx, buf->width);
+    }
+    
+    for(y=0;y<buf->height;y++) {
+        if(buf->lines[y].points) {
+            free(buf->lines[y].points);
+        }
+        memset(&buf->lines[y], 0, sizeof(renderline_t));
+    }
+    free(buf->lines);buf->lines=0;
+    return image;
+}
+
+#define MAX_WIDTH 8192
+#define MAX_HEIGHT 4096
+
+static inline max(double a, double b) {return a>b?a:b;}
+static inline min(double a, double b) {return a<b?a:b;}
+
+intbbox_t get_polygon_bbox(gfxpoly_t*polygon, double zoom)
+{
+    int t;
+    intbbox_t b = {0,0,0,0};
+    edge_t*e = polygon;
+
+    if(e) {
+        b.xmin = e->a.x;
+        b.ymin = e->a.y;
+        b.xmax = e->a.x;
+        b.ymax = e->a.y;
+    }
+    for(e=polygon;e;e=e->next) {
+        double x_min = min(e->a.x,e->b.x)*zoom;
+        double y_min = min(e->a.y,e->b.y)*zoom;
+        double x_max = max(e->a.x,e->b.x)*zoom;
+        double y_max = max(e->a.y,e->b.y)*zoom;
+        int x1 = floor(x_min);
+        int y1 = floor(y_min);
+        int x2 = ceil(x_max);
+        int y2 = ceil(y_max);
+        if(x1 < b.xmin) b.xmin = x1;
+        if(y1 < b.ymin) b.ymin = y1;
+        if(x2 > b.xmax) b.xmax = x2;
+        if(y2 > b.xmax) b.ymax = y2;
+    }
+    if(b.xmax > (int)(MAX_WIDTH*zoom))
+       b.xmax = (int)(MAX_WIDTH*zoom);
+    if(b.ymax > (int)(MAX_HEIGHT*zoom))
+       b.ymax = (int)(MAX_HEIGHT*zoom);
+    if(b.xmin < -(int)(MAX_WIDTH*zoom))
+       b.xmin = -(int)(MAX_WIDTH*zoom);
+    if(b.ymin < -(int)(MAX_HEIGHT*zoom))
+       b.ymin = -(int)(MAX_HEIGHT*zoom);
+    
+    if(b.xmin > b.xmax) 
+       b.xmin = b.xmax;
+    if(b.ymin > b.ymax) 
+       b.ymin = b.ymax;
+
+    b.width = b.xmax - b.xmin;
+    b.height = b.ymax - b.ymin;
+    return b;
+}
+
+#define B11100000 0xe0
+#define B01110000 0x70
+#define B00111000 0x38
+#define B00011100 0x1c
+#define B00001110 0x0e
+#define B00000111 0x07
+#define B10000000 0x80
+#define B01000000 0x40
+#define B00100000 0x20
+#define B00010000 0x10
+#define B00001000 0x08
+#define B00000100 0x04
+#define B00000010 0x02
+#define B00000001 0x01
+
+int compare_bitmaps(intbbox_t*bbox, unsigned char*data1, unsigned char*data2)
+{
+    int similar = 0;
+    int x,y;
+    int height = bbox->height;
+    int width = bbox->width;
+    int width8 = (width+7) >> 3;
+    unsigned char*l1 = &data1[width8];
+    unsigned char*l2 = &data2[width8];
+    int fail = 0;
+    for(y=1;y<height-1;y++) {
+        for(x=0;x<width8;x++) {
+            unsigned a = l1[x-width8] & l1[x] & l1[x+width8];
+            unsigned b = l2[x-width8] & l2[x] & l2[x+width8];
+
+            if((a&B11100000) && !(l2[x]&B01000000))
+                fail == 1;
+            if((a&B01110000) && !(l2[x]&B00100000))
+                fail == 1;
+            if((a&B00111000) && !(l2[x]&B00010000))
+                fail == 1;
+            if((a&B00011100) && !(l2[x]&B00001000))
+                fail == 1;
+            if((a&B00001110) && !(l2[x]&B00000100))
+                fail == 1;
+            if((a&B00000111) && !(l2[x]&B00000010))
+                fail == 1;
+
+            if((b&B11100000) && !(l1[x]&B01000000))
+                fail == 1;
+            if((b&B01110000) && !(l1[x]&B00100000))
+                fail == 1;
+            if((b&B00111000) && !(l1[x]&B00010000))
+                fail == 1;
+            if((b&B00011100) && !(l1[x]&B00001000))
+                fail == 1;
+            if((b&B00001110) && !(l1[x]&B00000100))
+                fail == 1;
+            if((b&B00000111) && !(l1[x]&B00000010))
+                fail == 1;
+        }
+        l1 += width8;
+        l2 += width8;
+    }
+    return !fail;
+}