/* * Portions of this file are copyright Rebirth contributors and licensed as * described in COPYING.txt. * Portions of this file are copyright Parallax Software and licensed * according to the Parallax license below. * See COPYING.txt for license details. THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE. COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED. */ /* * * Start of conversion to new texture mapper. * */ #include "pstypes.h" #include "maths.h" #include "vecmat.h" #include "gr.h" #include "3d.h" #include "dxxerror.h" #include "render.h" #include "texmap.h" #include "texmapl.h" #include "rle.h" #include "scanline.h" #include "u_mem.h" #include "dxxsconf.h" #include "compiler-integer_sequence.h" #ifdef EDITOR #define EDITOR_TMAP 1 //if in, include extra stuff #endif #define F15_5 (F1_0*15 + F0_5) // Temporary texture map, interface from Matt's 3d system to Mike's texture mapper. int Lighting_on=1; // initialize to no lighting unsigned Current_seg_depth; // HACK INTERFACE: how far away the current segment (& thus texture) is // These variables are the interface to assembler. They get set for each texture map, which is a real waste of time. // They should be set only when they change, which is generally when the window bounds change. And, even still, it's // a pretty bad interface. int bytes_per_row=-1; unsigned char *write_buffer; fix fx_l, fx_u, fx_v, fx_z, fx_du_dx, fx_dv_dx, fx_dz_dx, fx_dl_dx; int fx_xleft, fx_xright, fx_y; const unsigned char *pixptr; int Transparency_on = 0; ubyte tmap_flat_color; ubyte tmap_flat_shade_value; #ifndef OGL int Interpolation_method; // 0 = choose best method // ------------------------------------------------------------------------------------- template static inline constexpr const array init_fix_recip_table(index_sequence<0, N...>) { /* gcc 4.5 fails on bare initializer list */ return array{{F1_0, (F1_0 / N)...}}; } const array fix_recip_table = init_fix_recip_table(make_tree_index_sequence()); #endif // ------------------------------------------------------------------------------------- // Initialize interface variables to assembler. // These things used to be constants. This routine is now (10/6/93) getting called for // every texture map. It should get called whenever the window changes, or, preferably, // not at all. I'm pretty sure these variables are only being used for range checking. void init_interface_vars_to_assembler(void) { grs_bitmap *bp; bp = &grd_curcanv->cv_bitmap; Assert(bp!=NULL); Assert(bp->bm_data!=NULL); // If bytes_per_row has changed, create new table of pointers. if (bytes_per_row != (int) bp->bm_rowsize) { bytes_per_row = (int) bp->bm_rowsize; } write_buffer = bp->bm_mdata; Window_clip_left = 0; Window_clip_right = (int) bp->bm_w-1; Window_clip_top = 0; Window_clip_bot = (int) bp->bm_h-1; } #ifndef OGL static int Lighting_enabled; // ------------------------------------------------------------------------------------- // VARIABLES // ------------------------------------------------------------------------------------- // Returns number preceding val modulo modulus. // prevmod(3,4) = 2 // prevmod(0,4) = 3 int prevmod(int val,int modulus) { if (val > 0) return val-1; else return modulus-1; // return (val + modulus - 1) % modulus; } // Returns number succeeding val modulo modulus. // succmod(3,4) = 0 // succmod(0,4) = 1 int succmod(int val,int modulus) { if (val < modulus-1) return val+1; else return 0; // return (val + 1) % modulus; } // ------------------------------------------------------------------------------------- // Select topmost vertex (minimum y coordinate) and bottommost (maximum y coordinate) in // texture map. If either is part of a horizontal edge, then select leftmost vertex for // top, rightmost vertex for bottom. // Important: Vertex is selected with integer precision. So, if there are vertices at // (0.0,0.7) and (0.5,0.3), the first vertex is selected, because they y coordinates are // considered the same, so the smaller x is favored. // Parameters: // nv number of vertices // v3d pointer to 3d vertices containing u,v,x2d,y2d coordinates // Results in: // *min_y_ind // *max_y_ind // ------------------------------------------------------------------------------------- void compute_y_bounds(const g3ds_tmap &t, int &vlt, int &vlb, int &vrt, int &vrb,int &bottom_y_ind) { int min_y,max_y; int min_y_ind; int original_vrt; fix min_x; // Scan all vertices, set min_y_ind to vertex with smallest y coordinate. min_y = f2i(t.verts[0].y2d); max_y = min_y; min_y_ind = 0; min_x = f2i(t.verts[0].x2d); bottom_y_ind = 0; for (int i=1; i max_y) { max_y = f2i(t.verts[i].y2d); bottom_y_ind = i; } } //--removed mk, 11/27/94-- // Check for a non-upright-hourglass polygon and fix, if necessary, by bashing a y coordinate. //--removed mk, 11/27/94-- // min_y_ind = index of minimum y coordinate, *bottom_y_ind = index of maximum y coordinate //--removed mk, 11/27/94--{ //--removed mk, 11/27/94-- int max_temp, min_temp; //--removed mk, 11/27/94-- //--removed mk, 11/27/94-- max_temp = *bottom_y_ind; //--removed mk, 11/27/94-- if (*bottom_y_ind < min_y_ind) //--removed mk, 11/27/94-- max_temp += t->nv; //--removed mk, 11/27/94-- //--removed mk, 11/27/94-- for (i=min_y_ind; iverts[i%t->nv].y2d) > f2i(t->verts[(i+1)%t->nv].y2d)) { //--removed mk, 11/27/94-- Int3(); //--removed mk, 11/27/94-- t->verts[(i+1)%t->nv].y2d = t->verts[i%t->nv].y2d; //--removed mk, 11/27/94-- } //--removed mk, 11/27/94-- } //--removed mk, 11/27/94-- //--removed mk, 11/27/94-- min_temp = min_y_ind; //--removed mk, 11/27/94-- if (min_y_ind < *bottom_y_ind) //--removed mk, 11/27/94-- min_temp += t->nv; //--removed mk, 11/27/94-- //--removed mk, 11/27/94-- for (i=*bottom_y_ind; iverts[i%t->nv].y2d) < f2i(t->verts[(i+1)%t->nv].y2d)) { //--removed mk, 11/27/94-- Int3(); //--removed mk, 11/27/94-- t->verts[(i+1)%t->nv].y2d = t->verts[i%t->nv].y2d; //--removed mk, 11/27/94-- } //--removed mk, 11/27/94-- } //--removed mk, 11/27/94--} // Set "vertex left top", etc. based on vertex with topmost y coordinate vlb = prevmod(vlt = min_y_ind,t.nv); vrb = succmod(vrt = vlt,t.nv); // If right edge is horizontal, then advance along polygon bound until it no longer is or until all // vertices have been examined. // (Left edge cannot be horizontal, because *vlt is set to leftmost point with highest y coordinate.) original_vrt = vrt; while (f2i(t.verts[vrt].y2d) == f2i(t.verts[vrb].y2d)) { if (succmod(vrt,t.nv) == original_vrt) { break; } vrt = succmod(vrt,t.nv); vrb = succmod(vrt,t.nv); } } // ------------------------------------------------------------------------------------- // Returns dx/dy given two vertices. // If dy == 0, returns 0.0 // ------------------------------------------------------------------------------------- //--fix compute_dx_dy_lin(g3ds_tmap *t, int top_vertex,int bottom_vertex) //--{ //-- int dy; //-- //-- // compute delta x with respect to y for any edge //-- dy = f2i(t->verts[bottom_vertex].y2d - t->verts[top_vertex].y2d) + 1; //-- if (dy) //-- return (t->verts[bottom_vertex].x2d - t->verts[top_vertex].x2d) / dy; //-- else //-- return 0; //-- //--} //#ifndef OGL static fix compute_du_dy_lin(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(t.verts[bottom_vertex].u - t.verts[top_vertex].u, recip_dy); } static fix compute_dv_dy_lin(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(t.verts[bottom_vertex].v - t.verts[top_vertex].v, recip_dy); } static fix compute_dl_dy_lin(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(t.verts[bottom_vertex].l - t.verts[top_vertex].l, recip_dy); } fix compute_dx_dy(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(t.verts[bottom_vertex].x2d - t.verts[top_vertex].x2d, recip_dy); } static fix compute_du_dy(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(fixmul(t.verts[bottom_vertex].u,t.verts[bottom_vertex].z) - fixmul(t.verts[top_vertex].u,t.verts[top_vertex].z), recip_dy); } static fix compute_dv_dy(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(fixmul(t.verts[bottom_vertex].v,t.verts[bottom_vertex].z) - fixmul(t.verts[top_vertex].v,t.verts[top_vertex].z), recip_dy); } static fix compute_dz_dy(const g3ds_tmap &t, int top_vertex,int bottom_vertex, fix recip_dy) { return fixmul(t.verts[bottom_vertex].z - t.verts[top_vertex].z, recip_dy); } // ------------------------------------------------------------------------------------- // Texture map current scanline in perspective. // ------------------------------------------------------------------------------------- static void ntmap_scanline_lighted(const grs_bitmap &srcb, int y, fix xleft, fix xright, fix uleft, fix uright, fix vleft, fix vright, fix zleft, fix zright, fix lleft, fix lright) { fix dx,recip_dx; fx_xright = f2i(xright); //edited 06/27/99 Matt Mueller - moved these tests up from within the switch so as not to do a bunch of needless calculations when we are just gonna return anyway. Slight fps boost? if (fx_xright < Window_clip_left) return; fx_xleft = f2i(xleft); if (fx_xleft > Window_clip_right) return; //end edit -MM dx = fx_xright - fx_xleft; if ((dx < 0) || (xright < 0) || (xleft > xright)) // the (xleft > xright) term is not redundant with (dx < 0) because dx is computed using integers return; // setup to call assembler scanline renderer recip_dx = fix_recip(dx); fx_u = uleft; fx_v = vleft; fx_z = zleft; fx_du_dx = fixmul(uright - uleft,recip_dx); fx_dv_dx = fixmul(vright - vleft,recip_dx); fx_dz_dx = fixmul(zright - zleft,recip_dx); fx_y = y; pixptr = srcb.bm_data; switch (Lighting_enabled) { case 0: //added 05/17/99 Matt Mueller - prevent writing before the buffer if ((fx_y == 0) && (fx_xleft < 0)) fx_xleft = 0; //end addition -MM if (fx_xright > Window_clip_right) fx_xright = Window_clip_right; cur_tmap_scanline_per(); break; case 1: { fix mul_thing; if (lleft < 0) lleft = 0; if (lright < 0) lright = 0; if (lleft > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2)) lleft = (NUM_LIGHTING_LEVELS*F1_0-F1_0/2); if (lright > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2)) lright = (NUM_LIGHTING_LEVELS*F1_0-F1_0/2); fx_l = lleft; fx_dl_dx = fixmul(lright - lleft,recip_dx); // This is a pretty ugly hack to prevent lighting overflows. mul_thing = dx * fx_dl_dx; if (lleft + mul_thing < 0) fx_dl_dx += 12; else if (lleft + mul_thing > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2)) fx_dl_dx -= 12; //added 05/17/99 Matt Mueller - prevent writing before the buffer if ((fx_y == 0) && (fx_xleft < 0)) fx_xleft = 0; //end addition -MM if (fx_xright > Window_clip_right) fx_xright = Window_clip_right; cur_tmap_scanline_per(); break; } case 2: #ifdef EDITOR_TMAP fx_xright = f2i(xright); fx_xleft = f2i(xleft); tmap_flat_color = 1; cur_tmap_scanline_flat(); #else Int3(); // Illegal, called an editor only routine! #endif break; } } // ------------------------------------------------------------------------------------- // Render a texture map with lighting using perspective interpolation in inner and outer loops. // ------------------------------------------------------------------------------------- static void ntexture_map_lighted(const grs_bitmap &srcb, const g3ds_tmap &t) { int vlt,vrt,vlb,vrb; // vertex left top, vertex right top, vertex left bottom, vertex right bottom int topy,boty,dy; fix dx_dy_left,dx_dy_right; fix du_dy_left,du_dy_right; fix dv_dy_left,dv_dy_right; fix dz_dy_left,dz_dy_right; fix dl_dy_left,dl_dy_right; fix recip_dyl, recip_dyr; int max_y_vertex; fix xleft,xright,uleft,vleft,uright,vright,zleft,zright,lleft,lright; int next_break_left, next_break_right; //remove stupid warnings in compile dl_dy_left = F1_0; dl_dy_right = F1_0; lleft = F1_0; lright = F1_0; auto &v3d = t.verts; // Determine top and bottom y coords. compute_y_bounds(t,vlt,vlb,vrt,vrb,max_y_vertex); // Set top and bottom (of entire texture map) y coordinates. topy = f2i(v3d[vlt].y2d); boty = f2i(v3d[max_y_vertex].y2d); if (topy > Window_clip_bot) return; if (boty > Window_clip_bot) boty = Window_clip_bot; // Set amount to change x coordinate for each advance to next scanline. dy = f2i(t.verts[vlb].y2d) - f2i(t.verts[vlt].y2d); recip_dyl = fix_recip(dy); dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dyl); du_dy_left = compute_du_dy(t,vlt,vlb, recip_dyl); dv_dy_left = compute_dv_dy(t,vlt,vlb, recip_dyl); dz_dy_left = compute_dz_dy(t,vlt,vlb, recip_dyl); dy = f2i(t.verts[vrb].y2d) - f2i(t.verts[vrt].y2d); recip_dyr = fix_recip(dy); du_dy_right = compute_du_dy(t,vrt,vrb, recip_dyr); dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dyr); dv_dy_right = compute_dv_dy(t,vrt,vrb, recip_dyr); dz_dy_right = compute_dz_dy(t,vrt,vrb, recip_dyr); if (Lighting_enabled) { dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dyl); dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dyr); lleft = v3d[vlt].l; lright = v3d[vrt].l; } // Set initial values for x, u, v xleft = v3d[vlt].x2d; xright = v3d[vrt].x2d; zleft = v3d[vlt].z; zright = v3d[vrt].z; uleft = fixmul(v3d[vlt].u,zleft); uright = fixmul(v3d[vrt].u,zright); vleft = fixmul(v3d[vlt].v,zleft); vright = fixmul(v3d[vrt].v,zright); // scan all rows in texture map from top through first break. next_break_left = f2i(v3d[vlb].y2d); next_break_right = f2i(v3d[vrb].y2d); for (int y = topy; y < boty; y++) { // See if we have reached the end of the current left edge, and if so, set // new values for dx_dy and x,u,v if (y == next_break_left) { fix recip_dy; // Handle problem of double points. Search until y coord is different. Cannot get // hung in an infinite loop because we know there is a vertex with a lower y coordinate // because in the for loop, we don't scan all spanlines. while (y == f2i(v3d[vlb].y2d)) { vlt = vlb; vlb = prevmod(vlb,t.nv); } next_break_left = f2i(v3d[vlb].y2d); dy = f2i(t.verts[vlb].y2d) - f2i(t.verts[vlt].y2d); recip_dy = fix_recip(dy); dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dy); xleft = v3d[vlt].x2d; zleft = v3d[vlt].z; uleft = fixmul(v3d[vlt].u,zleft); vleft = fixmul(v3d[vlt].v,zleft); lleft = v3d[vlt].l; du_dy_left = compute_du_dy(t,vlt,vlb, recip_dy); dv_dy_left = compute_dv_dy(t,vlt,vlb, recip_dy); dz_dy_left = compute_dz_dy(t,vlt,vlb, recip_dy); if (Lighting_enabled) { dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dy); lleft = v3d[vlt].l; } } // See if we have reached the end of the current left edge, and if so, set // new values for dx_dy and x. Not necessary to set new values for u,v. if (y == next_break_right) { fix recip_dy; while (y == f2i(v3d[vrb].y2d)) { vrt = vrb; vrb = succmod(vrb,t.nv); } next_break_right = f2i(v3d[vrb].y2d); dy = f2i(t.verts[vrb].y2d) - f2i(t.verts[vrt].y2d); recip_dy = fix_recip(dy); dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dy); xright = v3d[vrt].x2d; zright = v3d[vrt].z; uright = fixmul(v3d[vrt].u,zright); vright = fixmul(v3d[vrt].v,zright); du_dy_right = compute_du_dy(t,vrt,vrb, recip_dy); dv_dy_right = compute_dv_dy(t,vrt,vrb, recip_dy); dz_dy_right = compute_dz_dy(t,vrt,vrb, recip_dy); if (Lighting_enabled) { dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dy); lright = v3d[vrt].l; } } if (Lighting_enabled) { if (y >= Window_clip_top) ntmap_scanline_lighted(srcb,y,xleft,xright,uleft,uright,vleft,vright,zleft,zright,lleft,lright); lleft += dl_dy_left; lright += dl_dy_right; } else if (y >= Window_clip_top) ntmap_scanline_lighted(srcb,y,xleft,xright,uleft,uright,vleft,vright,zleft,zright,lleft,lright); uleft += du_dy_left; vleft += dv_dy_left; uright += du_dy_right; vright += dv_dy_right; xleft += dx_dy_left; xright += dx_dy_right; zleft += dz_dy_left; zright += dz_dy_right; } // We can get lleft or lright out of bounds here because we compute dl_dy using fixed point values, // but we plot an integer number of scanlines, therefore doing an integer number of additions of the delta. ntmap_scanline_lighted(srcb,boty,xleft,xright,uleft,uright,vleft,vright,zleft,zright,lleft,lright); } // ------------------------------------------------------------------------------------- // Texture map current scanline using linear interpolation. // ------------------------------------------------------------------------------------- static void ntmap_scanline_lighted_linear(const grs_bitmap &srcb, int y, fix xleft, fix xright, fix uleft, fix uright, fix vleft, fix vright, fix lleft, fix lright) { fix dx,recip_dx,du_dx,dv_dx,dl_dx; dx = f2i(xright) - f2i(xleft); if ((dx < 0) || (xright < 0) || (xleft > xright)) // the (xleft > xright) term is not redundant with (dx < 0) because dx is computed using integers return; // setup to call assembler scanline renderer recip_dx = fix_recip(dx); du_dx = fixmul(uright - uleft,recip_dx); dv_dx = fixmul(vright - vleft,recip_dx); fx_u = uleft; fx_v = vleft; fx_du_dx = du_dx; fx_dv_dx = dv_dx; fx_y = y; fx_xright = f2i(xright); fx_xleft = f2i(xleft); pixptr = srcb.bm_data; switch (Lighting_enabled) { case 0: //added 07/11/99 adb - prevent writing before the buffer if (fx_xleft < 0) fx_xleft = 0; //end addition -adb cur_tmap_scanline_lin_nolight(); break; case 1: if (lleft < F1_0/2) lleft = F1_0/2; if (lright < F1_0/2) lright = F1_0/2; if (lleft > MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS) lleft = MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS; if (lright > MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS) lright = MAX_LIGHTING_VALUE*NUM_LIGHTING_LEVELS; //added 07/11/99 adb - prevent writing before the buffer if (fx_xleft < 0) fx_xleft = 0; //end addition -adb { fix mul_thing; fx_l = lleft; fx_dl_dx = fixmul(lright - lleft,recip_dx); // This is a pretty ugly hack to prevent lighting overflows. mul_thing = dx * fx_dl_dx; if (lleft + mul_thing < 0) fx_dl_dx += 12; else if (lleft + mul_thing > (NUM_LIGHTING_LEVELS*F1_0-F1_0/2)) fx_dl_dx -= 12; } fx_l = lleft; dl_dx = fixmul(lright - lleft,recip_dx); fx_dl_dx = dl_dx; cur_tmap_scanline_lin(); break; case 2: #ifdef EDITOR_TMAP fx_xright = f2i(xright); fx_xleft = f2i(xleft); tmap_flat_color = 1; cur_tmap_scanline_flat(); #else Int3(); // Illegal, called an editor only routine! #endif break; } } // ------------------------------------------------------------------------------------- // Render a texture map with lighting using perspective interpolation in inner and outer loops. // ------------------------------------------------------------------------------------- static void ntexture_map_lighted_linear(const grs_bitmap &srcb, const g3ds_tmap &t) { int vlt,vrt,vlb,vrb; // vertex left top, vertex right top, vertex left bottom, vertex right bottom int topy,boty,dy; fix dx_dy_left,dx_dy_right; fix du_dy_left,du_dy_right; fix dv_dy_left,dv_dy_right; fix dl_dy_left,dl_dy_right; int max_y_vertex; fix xleft,xright,uleft,vleft,uright,vright,lleft,lright; int next_break_left, next_break_right; fix recip_dyl, recip_dyr; //remove stupid warnings in compile dl_dy_left = F1_0; dl_dy_right = F1_0; lleft = F1_0; lright = F1_0; auto &v3d = t.verts; // Determine top and bottom y coords. compute_y_bounds(t,vlt,vlb,vrt,vrb,max_y_vertex); // Set top and bottom (of entire texture map) y coordinates. topy = f2i(v3d[vlt].y2d); boty = f2i(v3d[max_y_vertex].y2d); if (topy > Window_clip_bot) return; if (boty > Window_clip_bot) boty = Window_clip_bot; dy = f2i(t.verts[vlb].y2d) - f2i(t.verts[vlt].y2d); recip_dyl = fix_recip(dy); dy = f2i(t.verts[vrb].y2d) - f2i(t.verts[vrt].y2d); recip_dyr = fix_recip(dy); // Set amount to change x coordinate for each advance to next scanline. dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dyl); dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dyr); du_dy_left = compute_du_dy_lin(t,vlt,vlb, recip_dyl); du_dy_right = compute_du_dy_lin(t,vrt,vrb, recip_dyr); dv_dy_left = compute_dv_dy_lin(t,vlt,vlb, recip_dyl); dv_dy_right = compute_dv_dy_lin(t,vrt,vrb, recip_dyr); if (Lighting_enabled) { dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dyl); dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dyr); lleft = v3d[vlt].l; lright = v3d[vrt].l; } // Set initial values for x, u, v xleft = v3d[vlt].x2d; xright = v3d[vrt].x2d; uleft = v3d[vlt].u; uright = v3d[vrt].u; vleft = v3d[vlt].v; vright = v3d[vrt].v; // scan all rows in texture map from top through first break. next_break_left = f2i(v3d[vlb].y2d); next_break_right = f2i(v3d[vrb].y2d); for (int y = topy; y < boty; y++) { // See if we have reached the end of the current left edge, and if so, set // new values for dx_dy and x,u,v if (y == next_break_left) { fix recip_dy; // Handle problem of double points. Search until y coord is different. Cannot get // hung in an infinite loop because we know there is a vertex with a lower y coordinate // because in the for loop, we don't scan all spanlines. while (y == f2i(v3d[vlb].y2d)) { vlt = vlb; vlb = prevmod(vlb,t.nv); } next_break_left = f2i(v3d[vlb].y2d); dy = f2i(t.verts[vlb].y2d) - f2i(t.verts[vlt].y2d); recip_dy = fix_recip(dy); dx_dy_left = compute_dx_dy(t,vlt,vlb, recip_dy); xleft = v3d[vlt].x2d; uleft = v3d[vlt].u; vleft = v3d[vlt].v; lleft = v3d[vlt].l; du_dy_left = compute_du_dy_lin(t,vlt,vlb, recip_dy); dv_dy_left = compute_dv_dy_lin(t,vlt,vlb, recip_dy); if (Lighting_enabled) { dl_dy_left = compute_dl_dy_lin(t,vlt,vlb, recip_dy); lleft = v3d[vlt].l; } } // See if we have reached the end of the current left edge, and if so, set // new values for dx_dy and x. Not necessary to set new values for u,v. if (y == next_break_right) { fix recip_dy; while (y == f2i(v3d[vrb].y2d)) { vrt = vrb; vrb = succmod(vrb,t.nv); } dy = f2i(t.verts[vrb].y2d) - f2i(t.verts[vrt].y2d); recip_dy = fix_recip(dy); next_break_right = f2i(v3d[vrb].y2d); dx_dy_right = compute_dx_dy(t,vrt,vrb, recip_dy); xright = v3d[vrt].x2d; uright = v3d[vrt].u; vright = v3d[vrt].v; du_dy_right = compute_du_dy_lin(t,vrt,vrb, recip_dy); dv_dy_right = compute_dv_dy_lin(t,vrt,vrb, recip_dy); if (Lighting_enabled) { dl_dy_right = compute_dl_dy_lin(t,vrt,vrb, recip_dy); lright = v3d[vrt].l; } } if (Lighting_enabled) { ntmap_scanline_lighted_linear(srcb,y,xleft,xright,uleft,uright,vleft,vright,lleft,lright); lleft += dl_dy_left; lright += dl_dy_right; } else ntmap_scanline_lighted_linear(srcb,y,xleft,xright,uleft,uright,vleft,vright,lleft,lright); uleft += du_dy_left; vleft += dv_dy_left; uright += du_dy_right; vright += dv_dy_right; xleft += dx_dy_left; xright += dx_dy_right; } // We can get lleft or lright out of bounds here because we compute dl_dy using fixed point values, // but we plot an integer number of scanlines, therefore doing an integer number of additions of the delta. ntmap_scanline_lighted_linear(srcb,boty,xleft,xright,uleft,uright,vleft,vright,lleft,lright); } // fix DivNum = F1_0*12; // ------------------------------------------------------------------------------------- // Interface from Matt's data structures to Mike's texture mapper. // ------------------------------------------------------------------------------------- void draw_tmap(const grs_bitmap &rbp,uint_fast32_t nverts,const g3s_point *const *vertbuf) { // These variables are used in system which renders texture maps which lie on one scanline as a line. // fix div_numerator; int lighting_on_save = Lighting_on; Assert(nverts <= MAX_TMAP_VERTS); const grs_bitmap *bp = &rbp; // If no transparency and seg depth is large, render as flat shaded. if ((Current_seg_depth > Max_linear_depth) && ((bp->bm_flags & 3) == 0)) { draw_tmap_flat(rbp, nverts, vertbuf); return; } bp = rle_expand_texture(*bp); // Expand if rle'd Transparency_on = bp->bm_flags & BM_FLAG_TRANSPARENT; if (bp->bm_flags & BM_FLAG_NO_LIGHTING) Lighting_on = 0; // Setup texture map in Tmap1 g3ds_tmap Tmap1; Tmap1.nv = nverts; // Initialize number of vertices // div_numerator = DivNum; //f1_0*3; for (int i=0; ix2d = vp->p3_sx; tvp->y2d = vp->p3_sy; // Check for overflow on fixdiv. Will overflow on vp->z <= something small. Allow only as low as 256. auto clipped_p3_z = std::max(256, vp->p3_z); tvp->z = fixdiv(F1_0*12, clipped_p3_z); tvp->u = vp->p3_u << 6; //* bp->bm_w; tvp->v = vp->p3_v << 6; //* bp->bm_h; Assert(Lighting_on < 3); if (Lighting_on) tvp->l = vp->p3_l * NUM_LIGHTING_LEVELS; } Lighting_enabled = Lighting_on; // Now, call my texture mapper. if (Lighting_on) { switch (Interpolation_method) { // 0 = choose, 1 = linear, 2 = /8 perspective, 3 = full perspective case 0: // choose best interpolation if (Current_seg_depth > Max_perspective_depth) ntexture_map_lighted_linear(*bp, Tmap1); else ntexture_map_lighted(*bp, Tmap1); break; case 1: // linear interpolation ntexture_map_lighted_linear(*bp, Tmap1); break; case 2: // perspective every 8th pixel interpolation ntexture_map_lighted(*bp, Tmap1); break; case 3: // perspective every pixel interpolation ntexture_map_lighted(*bp, Tmap1); break; default: Assert(0); // Illegal value for Interpolation_method, must be 0,1,2,3 } } else { switch (Interpolation_method) { // 0 = choose, 1 = linear, 2 = /8 perspective, 3 = full perspective case 0: // choose best interpolation if (Current_seg_depth > Max_perspective_depth) ntexture_map_lighted_linear(*bp, Tmap1); else ntexture_map_lighted(*bp, Tmap1); break; case 1: // linear interpolation ntexture_map_lighted_linear(*bp, Tmap1); break; case 2: // perspective every 8th pixel interpolation ntexture_map_lighted(*bp, Tmap1); break; case 3: // perspective every pixel interpolation ntexture_map_lighted(*bp, Tmap1); break; default: Assert(0); // Illegal value for Interpolation_method, must be 0,1,2,3 } } Lighting_on = lighting_on_save; } #endif