/* * ***** BEGIN GPL LICENSE BLOCK ***** * * This program 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 2 * of the License, or (at your option) any later version. * * This program 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 this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * The Original Code is Copyright (C) 2012 Blender Foundation. * All rights reserved. * * The Original Code is: all of this file. * * Contributor(s): Peter Larabell. * * ***** END GPL LICENSE BLOCK ***** */ /** \file raskter.c * \ingroup RASKTER */ #include #include "raskter.h" #define __PLX__FAKE_AA__ /* from BLI_utildefines.h */ #define MIN2(x, y) ( (x) < (y) ? (x) : (y) ) #define MAX2(x, y) ( (x) > (y) ? (x) : (y) ) #define ABS(a) ( (a) < 0 ? (-(a)) : (a) ) struct e_status { int x; int ybeg; int xshift; int xdir; int drift; int drift_inc; int drift_dec; int num; struct e_status *e_next; }; struct r_buffer_stats { float *buf; int sizex; int sizey; }; struct r_fill_context { struct e_status *all_edges, *possible_edges; struct r_buffer_stats rb; }; /* * Sort all the edges of the input polygon by Y, then by X, of the "first" vertex encountered. * This will ensure we can scan convert the entire poly in one pass. * * Really the poly should be clipped to the frame buffer's dimensions here for speed of drawing * just the poly. Since the DEM code could end up being coupled with this, we'll keep it separate * for now. */ static void preprocess_all_edges(struct r_fill_context *ctx, struct poly_vert *verts, int num_verts, struct e_status *open_edge) { int i; int xbeg; int ybeg; int xend; int yend; int dx; int dy; int temp_pos; int xdist; struct e_status *e_new; struct e_status *next_edge; struct e_status **next_edge_ref; struct poly_vert *v; /* set up pointers */ v = verts; ctx->all_edges = NULL; /* loop all verts */ for (i = 0; i < num_verts; i++) { /* determine beginnings and endings of edges, linking last vertex to first vertex */ xbeg = v[i].x; ybeg = v[i].y; if (i) { /* we're not at the last vert, so end of the edge is the previous vertex */ xend = v[i - 1].x; yend = v[i - 1].y; } else { /* we're at the first vertex, so the "end" of this edge is the last vertex */ xend = v[num_verts - 1].x; yend = v[num_verts - 1].y; } /* make sure our edges are facing the correct direction */ if (ybeg > yend) { /* flip the Xs */ temp_pos = xbeg; xbeg = xend; xend = temp_pos; /* flip the Ys */ temp_pos = ybeg; ybeg = yend; yend = temp_pos; } /* calculate y delta */ dy = yend - ybeg; /* dont draw horizontal lines directly, they are scanned as part of the edges they connect, so skip em. :) */ if (dy) { /* create the edge and determine it's slope (for incremental line drawing) */ e_new = open_edge++; /* calculate x delta */ dx = xend - xbeg; if (dx > 0) { e_new->xdir = 1; xdist = dx; } else { e_new->xdir = -1; xdist = -dx; } e_new->x = xbeg; e_new->ybeg = ybeg; e_new->num = dy; e_new->drift_dec = dy; /* calculate deltas for incremental drawing */ if (dx >= 0) { e_new->drift = 0; } else { e_new->drift = -dy + 1; } if (dy >= xdist) { e_new->drift_inc = xdist; e_new->xshift = 0; } else { e_new->drift_inc = xdist % dy; e_new->xshift = (xdist / dy) * e_new->xdir; } next_edge_ref = &ctx->all_edges; /* link in all the edges, in sorted order */ for (;; ) { next_edge = *next_edge_ref; if (!next_edge || (next_edge->ybeg > ybeg) || ((next_edge->ybeg == ybeg) && (next_edge->x >= xbeg))) { e_new->e_next = next_edge; *next_edge_ref = e_new; break; } next_edge_ref = &next_edge->e_next; } } } } /* * This function clips drawing to the frame buffer. That clipping will likely be moved into the preprocessor * for speed, but waiting on final design choices for curve-data before eliminating data the DEM code will need * if it ends up being coupled with this function. */ static int rast_scan_fill(struct r_fill_context *ctx, struct poly_vert *verts, int num_verts, float intensity) { int x_curr; /* current pixel position in X */ int y_curr; /* current scan line being drawn */ int yp; /* y-pixel's position in frame buffer */ int swixd = 0; /* whether or not edges switched position in X */ float *cpxl; /* pixel pointers... */ float *mpxl; float *spxl; struct e_status *e_curr; /* edge pointers... */ struct e_status *e_temp; struct e_status *edgbuf; struct e_status **edgec; /* * If the number of verts specified to render as a polygon is less than 3, * return immediately. Obviously we cant render a poly with sides < 3. The * return for this we set to 1, simply so it can be distinguished from the * next place we could return. * which is a failure to allocate memory. */ if (num_verts < 3) { return(1); } /* * Try to allocate an edge buffer in memory. needs to be the size of the edge tracking data * multiplied by the number of edges, which is always equal to the number of verts in * a 2D polygon. Here we return 0 to indicate a memory allocation failure, as opposed to a 1 for * the preceeding error, which was a rasterization request on a 2D poly with less than * 3 sides. */ if ((edgbuf = (struct e_status *)(malloc(sizeof(struct e_status) * num_verts))) == NULL) { return(0); } /* * Do some preprocessing on all edges. This constructs a table structure in memory of all * the edge properties and can "flip" some edges so sorting works correctly. */ preprocess_all_edges(ctx, verts, num_verts, edgbuf); /* can happen with a zero area mask */ if (ctx->all_edges == NULL) { free(edgbuf); return(0); } /* * Set the pointer for tracking the edges currently in processing to NULL to make sure * we don't get some crazy value after initialization. */ ctx->possible_edges = NULL; /* * Loop through all scan lines to be drawn. Since we sorted by Y values during * preprocess_all_edges(), we can already exact values for the lowest and * highest Y values we could possibly need by induction. The preprocessing sorted * out edges by Y position, we can cycle the current edge being processed once * it runs out of Y pixels. When we have no more edges, meaning the current edge * is NULL after setting the "current" edge to be the previous current edge's * "next" edge in the Y sorted edge connection chain, we can stop looping Y values, * since we can't possibly have more scan lines if we ran out of edges. :) * * TODO: This clips Y to the frame buffer, which should be done in the preprocessor, but for now is done here. * Will get changed once DEM code gets in. */ for (y_curr = ctx->all_edges->ybeg; (ctx->all_edges || ctx->possible_edges); y_curr++) { /* * Link any edges that start on the current scan line into the list of * edges currently needed to draw at least this, if not several, scan lines. */ /* * Set the current edge to the beginning of the list of edges to be rasterized * into this scan line. * * We could have lots of edge here, so iterate over all the edges needed. The * preprocess_all_edges() function sorted edges by X within each chunk of Y sorting * so we safely cycle edges to thier own "next" edges in order. * * At each iteration, make sure we still have a non-NULL edge. */ for (edgec = &ctx->possible_edges; ctx->all_edges && (ctx->all_edges->ybeg == y_curr); ) { x_curr = ctx->all_edges->x; /* Set current X position. */ for (;; ) { /* Start looping edges. Will break when edges run out. */ e_curr = *edgec; /* Set up a current edge pointer. */ if (!e_curr || (e_curr->x >= x_curr)) { /* If we have an no edge, or we need to skip some X-span, */ e_temp = ctx->all_edges->e_next; /* set a temp "next" edge to test. */ *edgec = ctx->all_edges; /* Add this edge to the list to be scanned. */ ctx->all_edges->e_next = e_curr; /* Set up the next edge. */ edgec = &ctx->all_edges->e_next; /* Set our list to the next edge's location in memory. */ ctx->all_edges = e_temp; /* Skip the NULL or bad X edge, set pointer to next edge. */ break; /* Stop looping edges (since we ran out or hit empty X span. */ } else { edgec = &e_curr->e_next; /* Set the pointer to the edge list the "next" edge. */ } } } /* * Determine the current scan line's offset in the pixel buffer based on its Y position. * Basically we just multiply the current scan line's Y value by the number of pixels in each line. */ yp = y_curr * ctx->rb.sizex; /* * Set a "scan line pointer" in memory. The location of the buffer plus the row offset. */ spxl = ctx->rb.buf + (yp); /* * Set up the current edge to the first (in X) edge. The edges which could possibly be in this * list were determined in the preceeding edge loop above. They were already sorted in X by the * initial processing function. * * At each iteration, test for a NULL edge. Since we'll keep cycling edge's to their own "next" edge * we will eventually hit a NULL when the list runs out. */ for (e_curr = ctx->possible_edges; e_curr; e_curr = e_curr->e_next) { /* * Calculate a span of pixels to fill on the current scan line. * * Set the current pixel pointer by adding the X offset to the scan line's start offset. * Cycle the current edge the next edge. * Set the max X value to draw to be one less than the next edge's first pixel. This way we are * sure not to ever get into a situation where we have overdraw. (drawing the same pixel more than * one time because it's on a vertex connecting two edges) * * Then blast through all the pixels in the span, advancing the pointer and setting the color to white. * * TODO: Here we clip to the scan line, this is not efficient, and should be done in the preprocessor, * but for now it is done here until the DEM code comes in. */ /* set up xmin and xmax bounds on this scan line */ cpxl = spxl + MAX2(e_curr->x, 0); e_curr = e_curr->e_next; mpxl = spxl + MIN2(e_curr->x, ctx->rb.sizex) - 1; if ((y_curr >= 0) && (y_curr < ctx->rb.sizey)) { /* draw the pixels. */ for(; cpxl <= mpxl; *cpxl++ += intensity); } } /* * Loop through all edges of polygon that could be hit by this scan line, * and figure out their x-intersections with the next scan line. * * Either A.) we wont have any more edges to test, or B.) we just add on the * slope delta computed in preprocessing step. Since this draws non-antialiased * polygons, we dont have fractional positions, so we only move in x-direction * when needed to get all the way to the next pixel over... */ for (edgec = &ctx->possible_edges; (e_curr = *edgec); ) { if (!(--(e_curr->num))) { *edgec = e_curr->e_next; } else { e_curr->x += e_curr->xshift; if ((e_curr->drift += e_curr->drift_inc) > 0) { e_curr->x += e_curr->xdir; e_curr->drift -= e_curr->drift_dec; } edgec = &e_curr->e_next; } } /* * It's possible that some edges may have crossed during the last step, so we'll be sure * that we ALWAYS intersect scan lines in order by shuffling if needed to make all edges * sorted by x-intersection coordinate. We'll always scan through at least once to see if * edges crossed, and if so, we set the 'swixd' flag. If 'swixd' gets set on the initial * pass, then we know we need to sort by x, so then cycle through edges again and perform * the sort.- */ if (ctx->possible_edges) { for (edgec = &ctx->possible_edges; (e_curr = *edgec)->e_next; edgec = &(*edgec)->e_next) { /* if the current edge hits scan line at greater X than the next edge, we need to exchange the edges */ if (e_curr->x > e_curr->e_next->x) { *edgec = e_curr->e_next; /* exchange the pointers */ e_temp = e_curr->e_next->e_next; e_curr->e_next->e_next = e_curr; e_curr->e_next = e_temp; /* set flag that we had at least one switch */ swixd = 1; } } /* if we did have a switch, look for more (there will more if there was one) */ for (;; ) { /* reset exchange flag so it's only set if we encounter another one */ swixd = 0; for (edgec = &ctx->possible_edges; (e_curr = *edgec)->e_next; edgec = &(*edgec)->e_next) { /* again, if current edge hits scan line at higher X than next edge, exchange the edges and set flag */ if (e_curr->x > e_curr->e_next->x) { *edgec = e_curr->e_next; /* exchange the pointers */ e_temp = e_curr->e_next->e_next; e_curr->e_next->e_next = e_curr; e_curr->e_next = e_temp; /* flip the exchanged flag */ swixd = 1; } } /* if we had no exchanges, we're done reshuffling the pointers */ if (!swixd) { break; } } } } free(edgbuf); return 1; } int PLX_raskterize(float (*base_verts)[2], int num_base_verts, float *buf, int buf_x, int buf_y, int do_mask_AA) { int subdiv_AA = (do_mask_AA != 0) ? 8 : 0; int i; /* i: Loop counter. */ int sAx; int sAy; struct poly_vert *ply; /* ply: Pointer to a list of integer buffer-space vertex coordinates. */ struct r_fill_context ctx = {0}; const float buf_x_f = (float)(buf_x); const float buf_y_f = (float)(buf_y); float div_offset = (1.0f / (float)(subdiv_AA)); float div_offset_static = 0.5f * (float)(subdiv_AA) * div_offset; /* * Allocate enough memory for our poly_vert list. It'll be the size of the poly_vert * data structure multiplied by the number of base_verts. * * In the event of a failure to allocate the memory, return 0, so this error can * be distinguished as a memory allocation error. */ if ((ply = (struct poly_vert *)(malloc(sizeof(struct poly_vert) * num_base_verts))) == NULL) { return(0); } ctx.rb.buf = buf; /* Set the output buffer pointer. */ ctx.rb.sizex = buf_x; /* Set the output buffer size in X. (width) */ ctx.rb.sizey = buf_y; /* Set the output buffer size in Y. (height) */ /* * Loop over all verts passed in to be rasterized. Each vertex's X and Y coordinates are * then converted from normalized screen space (0.0 <= POS <= 1.0) to integer coordinates * in the buffer-space coordinates passed in inside buf_x and buf_y. * * It's worth noting that this function ONLY outputs fully white pixels in a mask. Every pixel * drawn will be 1.0f in value, there is no anti-aliasing. */ if (!subdiv_AA) { for (i = 0; i < num_base_verts; i++) { /* Loop over all base_verts. */ ply[i].x = (int)((base_verts[i][0] * buf_x_f) + 0.5f); /* Range expand normalized X to integer buffer-space X. */ ply[i].y = (int)((base_verts[i][1] * buf_y_f) + 0.5f); /* Range expand normalized Y to integer buffer-space Y. */ } i = rast_scan_fill(&ctx, ply, num_base_verts, 1.0f); /* Call our rasterizer, passing in the integer coords for each vert. */ } else { for (sAx = 0; sAx < subdiv_AA; sAx++) { for (sAy = 0; sAy < subdiv_AA; sAy++) { for (i = 0; i < num_base_verts; i++) { ply[i].x = (int)((base_verts[i][0] * buf_x_f) + 0.5f - div_offset_static + (div_offset * (float)(sAx))); ply[i].y = (int)((base_verts[i][1] * buf_y_f) + 0.5f - div_offset_static + (div_offset * (float)(sAy))); } i = rast_scan_fill(&ctx, ply, num_base_verts, (1.0f / (float)(subdiv_AA * subdiv_AA))); } } } free(ply); /* Free the memory allocated for the integer coordinate table. */ return(i); /* Return the value returned by the rasterizer. */ } /* * This function clips drawing to the frame buffer. That clipping will likely be moved into the preprocessor * for speed, but waiting on final design choices for curve-data before eliminating data the DEM code will need * if it ends up being coupled with this function. */ static int rast_scan_feather(struct r_fill_context *ctx, float (*base_verts_f)[2], int num_base_verts, struct poly_vert *feather_verts, float(*feather_verts_f)[2], int num_feather_verts) { int x_curr; /* current pixel position in X */ int y_curr; /* current scan line being drawn */ int yp; /* y-pixel's position in frame buffer */ int swixd = 0; /* whether or not edges switched position in X */ float *cpxl; /* pixel pointers... */ float *mpxl; float *spxl; struct e_status *e_curr; /* edge pointers... */ struct e_status *e_temp; struct e_status *edgbuf; struct e_status **edgec; /* from dem */ int a; // a = temporary pixel index buffer loop counter float fsz; // size of the frame unsigned int rsl; // long used for finding fast 1.0/sqrt float rsf; // float used for finding fast 1.0/sqrt const float rsopf = 1.5f; // constant float used for finding fast 1.0/sqrt //unsigned int gradientFillOffset; float t; float ud; // ud = unscaled edge distance float dmin; // dmin = minimun edge distance float odist; // odist = current outer edge distance float idist; // idist = current inner edge distance float dx; // dx = X-delta (used for distance proportion calculation) float dy; // dy = Y-delta (used for distance proportion calculation) float xpxw = (1.0f / (float)(ctx->rb.sizex)); // xpxw = normalized pixel width float ypxh = (1.0f / (float)(ctx->rb.sizey)); // ypxh = normalized pixel height /* * If the number of verts specified to render as a polygon is less than 3, * return immediately. Obviously we cant render a poly with sides < 3. The * return for this we set to 1, simply so it can be distinguished from the * next place we could return, /home/guest/blender-svn/soc-2011-tomato/intern/raskter/raskter * which is a failure to allocate memory. */ if (num_feather_verts < 3) { return(1); } /* * Try to allocate an edge buffer in memory. needs to be the size of the edge tracking data * multiplied by the number of edges, which is always equal to the number of verts in * a 2D polygon. Here we return 0 to indicate a memory allocation failure, as opposed to a 1 for * the preceeding error, which was a rasterization request on a 2D poly with less than * 3 sides. */ if ((edgbuf = (struct e_status *)(malloc(sizeof(struct e_status) * num_feather_verts))) == NULL) { return(0); } /* can happen with a zero area mask */ if (ctx->all_edges == NULL) { free(edgbuf); return(0); } /* * Do some preprocessing on all edges. This constructs a table structure in memory of all * the edge properties and can "flip" some edges so sorting works correctly. */ preprocess_all_edges(ctx, feather_verts, num_feather_verts, edgbuf); /* * Set the pointer for tracking the edges currently in processing to NULL to make sure * we don't get some crazy value after initialization. */ ctx->possible_edges = NULL; /* * Loop through all scan lines to be drawn. Since we sorted by Y values during * preprocess_all_edges(), we can already exact values for the lowest and * highest Y values we could possibly need by induction. The preprocessing sorted * out edges by Y position, we can cycle the current edge being processed once * it runs out of Y pixels. When we have no more edges, meaning the current edge * is NULL after setting the "current" edge to be the previous current edge's * "next" edge in the Y sorted edge connection chain, we can stop looping Y values, * since we can't possibly have more scan lines if we ran out of edges. :) * * TODO: This clips Y to the frame buffer, which should be done in the preprocessor, but for now is done here. * Will get changed once DEM code gets in. */ for (y_curr = ctx->all_edges->ybeg; (ctx->all_edges || ctx->possible_edges); y_curr++) { /* * Link any edges that start on the current scan line into the list of * edges currently needed to draw at least this, if not several, scan lines. */ /* * Set the current edge to the beginning of the list of edges to be rasterized * into this scan line. * * We could have lots of edge here, so iterate over all the edges needed. The * preprocess_all_edges() function sorted edges by X within each chunk of Y sorting * so we safely cycle edges to thier own "next" edges in order. * * At each iteration, make sure we still have a non-NULL edge. */ for (edgec = &ctx->possible_edges; ctx->all_edges && (ctx->all_edges->ybeg == y_curr); ) { x_curr = ctx->all_edges->x; /* Set current X position. */ for (;; ) { /* Start looping edges. Will break when edges run out. */ e_curr = *edgec; /* Set up a current edge pointer. */ if (!e_curr || (e_curr->x >= x_curr)) { /* If we have an no edge, or we need to skip some X-span, */ e_temp = ctx->all_edges->e_next; /* set a temp "next" edge to test. */ *edgec = ctx->all_edges; /* Add this edge to the list to be scanned. */ ctx->all_edges->e_next = e_curr; /* Set up the next edge. */ edgec = &ctx->all_edges->e_next; /* Set our list to the next edge's location in memory. */ ctx->all_edges = e_temp; /* Skip the NULL or bad X edge, set pointer to next edge. */ break; /* Stop looping edges (since we ran out or hit empty X span. */ } else { edgec = &e_curr->e_next; /* Set the pointer to the edge list the "next" edge. */ } } } /* * Determine the current scan line's offset in the pixel buffer based on its Y position. * Basically we just multiply the current scan line's Y value by the number of pixels in each line. */ yp = y_curr * ctx->rb.sizex; /* * Set a "scan line pointer" in memory. The location of the buffer plus the row offset. */ spxl = ctx->rb.buf + (yp); /* * Set up the current edge to the first (in X) edge. The edges which could possibly be in this * list were determined in the preceeding edge loop above. They were already sorted in X by the * initial processing function. * * At each iteration, test for a NULL edge. Since we'll keep cycling edge's to their own "next" edge * we will eventually hit a NULL when the list runs out. */ for (e_curr = ctx->possible_edges; e_curr; e_curr = e_curr->e_next) { /* * Calculate a span of pixels to fill on the current scan line. * * Set the current pixel pointer by adding the X offset to the scan line's start offset. * Cycle the current edge the next edge. * Set the max X value to draw to be one less than the next edge's first pixel. This way we are * sure not to ever get into a situation where we have overdraw. (drawing the same pixel more than * one time because it's on a vertex connecting two edges) * * Then blast through all the pixels in the span, advancing the pointer and setting the color to white. * * TODO: Here we clip to the scan line, this is not efficient, and should be done in the preprocessor, * but for now it is done here until the DEM code comes in. */ /* set up xmin and xmax bounds on this scan line */ cpxl = spxl + MAX2(e_curr->x, 0); e_curr = e_curr->e_next; mpxl = spxl + MIN2(e_curr->x, ctx->rb.sizex) - 1; if ((y_curr >= 0) && (y_curr < ctx->rb.sizey)) { t = ((float)((cpxl - spxl) % ctx->rb.sizex) + 0.5f) * xpxw; fsz = ((float)(y_curr) + 0.5f) * ypxh; /* draw the pixels. */ for (; cpxl <= mpxl; cpxl++, t += xpxw) { //do feather check // first check that pixel isn't already full, and only operate if it is not if (*cpxl < 0.9999f) { dmin = 2.0f; // reset min distance to edge pixel for (a = 0; a < num_feather_verts; a++) { // loop through all outer edge buffer pixels dy = t - feather_verts_f[a][0]; // set dx to gradient pixel column - outer edge pixel row dx = fsz - feather_verts_f[a][1]; // set dy to gradient pixel row - outer edge pixel column ud = dx * dx + dy * dy; // compute sum of squares if (ud < dmin) { // if our new sum of squares is less than the current minimum dmin = ud; // set a new minimum equal to the new lower value } } odist = dmin; // cast outer min to a float rsf = odist * 0.5f; // rsl = *(unsigned int *)&odist; // use some peculiar properties of the way bits are stored rsl = 0x5f3759df - (rsl >> 1); // in floats vs. unsigned ints to compute an approximate odist = *(float *)&rsl; // reciprocal square root odist = odist * (rsopf - (rsf * odist * odist)); // -- ** this line can be iterated for more accuracy ** -- odist = odist * (rsopf - (rsf * odist * odist)); dmin = 2.0f; // reset min distance to edge pixel for (a = 0; a < num_base_verts; a++) { // loop through all inside edge pixels dy = t - base_verts_f[a][0]; // compute delta in Y from gradient pixel to inside edge pixel dx = fsz - base_verts_f[a][1]; // compute delta in X from gradient pixel to inside edge pixel ud = dx * dx + dy * dy; // compute sum of squares if (ud < dmin) { // if our new sum of squares is less than the current minimum we've found dmin = ud; // set a new minimum equal to the new lower value } } idist = dmin; // cast inner min to a float rsf = idist * 0.5f; // rsl = *(unsigned int *)&idist; // rsl = 0x5f3759df - (rsl >> 1); // see notes above idist = *(float *)&rsl; // idist = idist * (rsopf - (rsf * idist * idist)); // idist = idist * (rsopf - (rsf * idist * idist)); /* * Note once again that since we are using reciprocals of distance values our * proportion is already the correct intensity, and does not need to be * subracted from 1.0 like it would have if we used real distances. */ /* set intensity, do the += so overlapping gradients are additive */ *cpxl = (idist / (idist + odist)); } } } } /* * Loop through all edges of polygon that could be hit by this scan line, * and figure out their x-intersections with the next scan line. * * Either A.) we wont have any more edges to test, or B.) we just add on the * slope delta computed in preprocessing step. Since this draws non-antialiased * polygons, we dont have fractional positions, so we only move in x-direction * when needed to get all the way to the next pixel over... */ for (edgec = &ctx->possible_edges; (e_curr = *edgec); ) { if (!(--(e_curr->num))) { *edgec = e_curr->e_next; } else { e_curr->x += e_curr->xshift; if ((e_curr->drift += e_curr->drift_inc) > 0) { e_curr->x += e_curr->xdir; e_curr->drift -= e_curr->drift_dec; } edgec = &e_curr->e_next; } } /* * It's possible that some edges may have crossed during the last step, so we'll be sure * that we ALWAYS intersect scan lines in order by shuffling if needed to make all edges * sorted by x-intersection coordinate. We'll always scan through at least once to see if * edges crossed, and if so, we set the 'swixd' flag. If 'swixd' gets set on the initial * pass, then we know we need to sort by x, so then cycle through edges again and perform * the sort.- */ if (ctx->possible_edges) { for (edgec = &ctx->possible_edges; (e_curr = *edgec)->e_next; edgec = &(*edgec)->e_next) { /* if the current edge hits scan line at greater X than the next edge, we need to exchange the edges */ if (e_curr->x > e_curr->e_next->x) { *edgec = e_curr->e_next; /* exchange the pointers */ e_temp = e_curr->e_next->e_next; e_curr->e_next->e_next = e_curr; e_curr->e_next = e_temp; /* set flag that we had at least one switch */ swixd = 1; } } /* if we did have a switch, look for more (there will more if there was one) */ for (;; ) { /* reset exchange flag so it's only set if we encounter another one */ swixd = 0; for (edgec = &ctx->possible_edges; (e_curr = *edgec)->e_next; edgec = &(*edgec)->e_next) { /* again, if current edge hits scan line at higher X than next edge, * exchange the edges and set flag */ if (e_curr->x > e_curr->e_next->x) { *edgec = e_curr->e_next; /* exchange the pointers */ e_temp = e_curr->e_next->e_next; e_curr->e_next->e_next = e_curr; e_curr->e_next = e_temp; /* flip the exchanged flag */ swixd = 1; } } /* if we had no exchanges, we're done reshuffling the pointers */ if (!swixd) { break; } } } } free(edgbuf); return 1; } int PLX_raskterize_feather(float (*base_verts)[2], int num_base_verts, float (*feather_verts)[2], int num_feather_verts, float *buf, int buf_x, int buf_y) { int i; /* i: Loop counter. */ struct poly_vert *fe; /* fe: Pointer to a list of integer buffer-space feather vertex coords. */ struct r_fill_context ctx = {0}; /* for faster multiply */ const float buf_x_f = (float)buf_x; const float buf_y_f = (float)buf_y; /* * Allocate enough memory for our poly_vert list. It'll be the size of the poly_vert * data structure multiplied by the number of verts. * * In the event of a failure to allocate the memory, return 0, so this error can * be distinguished as a memory allocation error. */ if ((fe = (struct poly_vert *)(malloc(sizeof(struct poly_vert) * num_feather_verts))) == NULL) { return(0); } /* * Loop over all verts passed in to be rasterized. Each vertex's X and Y coordinates are * then converted from normalized screen space (0.0 <= POS <= 1.0) to integer coordinates * in the buffer-space coordinates passed in inside buf_x and buf_y. * * It's worth noting that this function ONLY outputs fully white pixels in a mask. Every pixel * drawn will be 1.0f in value, there is no anti-aliasing. */ for (i = 0; i < num_feather_verts; i++) { /* Loop over all verts. */ fe[i].x = (int)((feather_verts[i][0] * buf_x_f) + 0.5f); /* Range expand normalized X to integer buffer-space X. */ fe[i].y = (int)((feather_verts[i][1] * buf_y_f) + 0.5f); /* Range expand normalized Y to integer buffer-space Y. */ } ctx.rb.buf = buf; /* Set the output buffer pointer. */ ctx.rb.sizex = buf_x; /* Set the output buffer size in X. (width) */ ctx.rb.sizey = buf_y; /* Set the output buffer size in Y. (height) */ /* Call our rasterizer, passing in the integer coords for each vert. */ i = rast_scan_feather(&ctx, base_verts, num_base_verts, fe, feather_verts, num_feather_verts); free(fe); return i; /* Return the value returned by the rasterizer. */ } #ifndef __PLX__FAKE_AA__ static int get_range_expanded_pixel_coord(float normalized_value, int max_value) { return (int)((normalized_value * (float)(max_value)) + 0.5f); } static float get_pixel_intensity(float *buf, int buf_x, int buf_y, int pos_x, int pos_y) { if(pos_x < 0 || pos_x >= buf_x || pos_y < 0 || pos_y >= buf_y) { return 0.0f; } return buf[(pos_y * buf_y) + buf_x]; } static float get_pixel_intensity_bilinear(float *buf, int buf_x, int buf_y, float u, float v) { int a; int b; int a_plus_1; int b_plus_1; float prop_u; float prop_v; float inv_prop_u; float inv_prop_v; if(u<0.0f || u>1.0f || v<0.0f || v>1.0f) { return 0.0f; } u = u * (float)(buf_x) - 0.5f; v = v * (float)(buf_y) - 0.5f; a = (int)(u); b = (int)(v); prop_u = u - (float)(a); prop_v = v - (float)(b); inv_prop_u = 1.0f - prop_u; inv_prop_v = 1.0f - prop_v; a_plus_1 = MIN2((buf_x-1),a+1); b_plus_1 = MIN2((buf_y-1),b+1); return (buf[(b * buf_y) + a] * inv_prop_u + buf[(b*buf_y)+(a_plus_1)] * prop_u)*inv_prop_v+(buf[((b_plus_1) * buf_y)+a] * inv_prop_u + buf[((b_plus_1)*buf_y)+(a_plus_1)] * prop_u) * prop_v; } static void set_pixel_intensity(float *buf, int buf_x, int buf_y, int pos_x, int pos_y, float intensity) { if(pos_x < 0 || pos_x >= buf_x || pos_y < 0 || pos_y >= buf_y) { return; } buf[(pos_y * buf_y) + buf_x] = intensity; } #endif int PLX_antialias_buffer(float *buf, int buf_x, int buf_y) { #ifdef __PLX__FAKE_AA__ #ifdef __PLX_GREY_AA__ int i=0; int sz = buf_x * buf_y; for(i=0; i= edgeVert ? 1:0; subpixA = subpixNSWE * 2.0f + subpixNWSWNESE; if(!horzSpan) { lumaN = lumaW; lumaS = lumaE; } else { lengthSign = 1.0f / (float)(buf_y); } subpixB = (subpixA * (1.0f/12.0f)) - lumaM; gradientN = lumaN - lumaM; gradientS = lumaS - lumaM; lumaNN = lumaN + lumaM; lumaSS = lumaS + lumaM; pairN = (ABS(gradientN)) >= (ABS(gradientS)) ? 1:0; gradient = MAX2(ABS(gradientN), ABS(gradientS)); if(pairN) { lengthSign = -lengthSign; } subpixC = MAX2(MIN2(ABS(subpixB) * subpixRcpRange,1.0f),0.0f); posB_x = posM_x; posB_y = posM_y; offNP_x = (!horzSpan) ? 0.0f:(1.0f / (float)(buf_x)); offNP_y = (horzSpan) ? 0.0f:(1.0f / (float)(buf_y)); if(!horzSpan) { posB_x += lengthSign * 0.5f; } else { posB_y += lengthSign * 0.5f; } posN_x = posB_x - offNP_x * p0; posN_y = posB_y - offNP_y * p0; posP_x = posB_x + offNP_x * p0; posP_y = posB_y + offNP_y * p0; subpixD = ((-2.0f)*subpixC) + 3.0f; //may need bilinear filtered get_pixel_intensity() here...done lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); subpixE = subpixC * subpixC; //may need bilinear filtered get_pixel_intensity() here...done lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); if(!pairN) { lumaNN = lumaSS; } gradientScaled = gradient * 1.0f/4.0f; lumaMM =lumaM - lumaNN * 0.5f; subpixF = subpixD * subpixE; lumaMLTZero = lumaMM < 0.0f ? 1:0; lumaEndN -= lumaNN * 0.5f; lumaEndP -= lumaNN * 0.5f; doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p1; posN_y -= offNP_y * p1; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p1; posP_y += offNP_y * p1; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x, posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p2; posN_y -= offNP_y * p2; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p2; posP_y += offNP_y * p2; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p3; posN_y -= offNP_y * p3; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p3; posP_y += offNP_y * p3; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p4; posN_y -= offNP_y * p4; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p4; posP_y += offNP_y * p4; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p5; posN_y -= offNP_y * p5; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p5; posP_y += offNP_y * p5; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p6; posN_y -= offNP_y * p6; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p6; posP_y += offNP_y * p6; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p7; posN_y -= offNP_y * p7; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p7; posP_y += offNP_y * p7; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p8; posN_y -= offNP_y * p8; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p8; posP_y += offNP_y * p8; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p9; posN_y -= offNP_y * p9; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p9; posP_y += offNP_y * p9; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p10; posN_y -= offNP_y * p10; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p10; posP_y += offNP_y * p10; } if(doneNP) { if(!doneN) { lumaEndN = get_pixel_intensity_bilinear(buf, buf_x, buf_y,posN_x,posN_y); } if(!doneP) { lumaEndP = get_pixel_intensity_bilinear(buf, buf_x, buf_y, posP_x,posP_y); } if(!doneN) { lumaEndN = lumaEndN - lumaNN * 0.5; } if(!doneP) { lumaEndP = lumaEndP - lumaNN * 0.5; } doneN = (ABS(lumaEndN)) >= gradientScaled ? 1:0; doneP = (ABS(lumaEndP)) >= gradientScaled ? 1:0; if(!doneN) { posN_x -= offNP_x * p11; posN_y -= offNP_y * p11; } doneNP = (!doneN) || (!doneP) ? 1:0; if(!doneP) { posP_x += offNP_x * p11; posP_y += offNP_y * p11; } } } } } } } } } } } dstN = posM_x - posN_x; dstP = posP_x - posM_x; if(!horzSpan) { dstN = posM_y - posN_y; dstP = posP_y - posM_y; } goodSpanN = ((lumaEndN < 0.0f) ? 1:0) != lumaMLTZero ? 1:0; spanLength = (dstP + dstN); goodSpanP = ((lumaEndP < 0.0f) ? 1:0) != lumaMLTZero ? 1:0; spanLengthRcp = 1.0f/spanLength; directionN = dstN < dstP ? 1:0; dst = MIN2(dstN, dstP); goodSpan = (directionN==1) ? goodSpanN:goodSpanP; subpixG = subpixF * subpixF; pixelOffset = (dst * (-spanLengthRcp)) + 0.5f; subpixH = subpixG * quality_subpix; pixelOffsetGood = (goodSpan==1) ? pixelOffset : 0.0f; pixelOffsetSubpix = MAX2(pixelOffsetGood, subpixH); if(!horzSpan) { posM_x += pixelOffsetSubpix * lengthSign; } else { posM_y += pixelOffsetSubpix * lengthSign; } //may need bilinear filtered get_pixel_intensity() here... set_pixel_intensity(buf,buf_x,buf_y,curr_x,curr_y,get_pixel_intensity_bilinear(buf, buf_x, buf_y, posM_x,posM_y)* lumaM); } } return 1; #endif }