diff options
Diffstat (limited to 'generator/pamtris/triangle.c')
| -rw-r--r-- | generator/pamtris/triangle.c | 274 |
1 files changed, 87 insertions, 187 deletions
diff --git a/generator/pamtris/triangle.c b/generator/pamtris/triangle.c index 09d821e0..5143f9ee 100644 --- a/generator/pamtris/triangle.c +++ b/generator/pamtris/triangle.c @@ -9,7 +9,7 @@ #include "netpbm/mallocvar.h" #include "utils.h" -#include "fract.h" +#include "varying.h" #include "boundaries.h" #include "framebuffer.h" @@ -17,29 +17,30 @@ static void draw_partial_triangle( - const fract * const left_attribs_input, - const fract * const left_attribs_steps, - const fract * const rght_attribs_input, - const fract * const rght_attribs_steps, - int32_t const left_div, - int32_t const rght_div, + const varying * const left_attribs_input, + const varying * const rght_attribs_input, bool const upper_part, const boundary_info * const bi, framebuffer_info * const fbi) { - uint8_t const num_planes = fbi->num_attribs + 1; + uint8_t const z = fbi->num_attribs; + uint8_t const w = z + 1; + uint8_t const n = w + 1; - fract * left_attribs; - fract * rght_attribs; + varying * left_attribs; + varying * rght_attribs; + + varying * attribs; int32_t first_row_index; int32_t last_row_index; - MALLOCARRAY_NOFAIL(left_attribs, num_planes); - MALLOCARRAY_NOFAIL(rght_attribs, num_planes); + MALLOCARRAY_NOFAIL(left_attribs, n); + MALLOCARRAY_NOFAIL(rght_attribs, n); + MALLOCARRAY_NOFAIL(attribs, n); - memcpy(left_attribs, left_attribs_input, num_planes * sizeof(fract)); - memcpy(rght_attribs, rght_attribs_input, num_planes * sizeof(fract)); + memcpy(left_attribs, left_attribs_input, n * sizeof(varying)); + memcpy(rght_attribs, rght_attribs_input, n * sizeof(varying)); if (upper_part) { first_row_index = 0; @@ -57,41 +58,26 @@ draw_partial_triangle( int32_t left_boundary; int32_t rght_boundary; - for (row = first_row_index; row <= last_row_index; ) { + for (row = first_row_index; row <= last_row_index; row++) { get_triangle_boundaries(row, &left_boundary, &rght_boundary, bi); { int32_t const column_delta = rght_boundary - left_boundary; int32_t start_column; int32_t span_length; - fract * attribs_start; - int32_t * attribs_begin; - int32_t * attribs_end; - fract * attribs_steps; - - MALLOCARRAY_NOFAIL(attribs_start, num_planes); - MALLOCARRAY_NOFAIL(attribs_begin, num_planes); - MALLOCARRAY_NOFAIL(attribs_end, num_planes); - MALLOCARRAY_NOFAIL(attribs_steps, num_planes); - start_column = left_boundary; /* initial value */ span_length = column_delta; /* initial value */ - fract_to_int32_array(left_attribs, attribs_begin, num_planes); - fract_to_int32_array(rght_attribs, attribs_end, num_planes); - - int32_to_fract_array(attribs_begin, attribs_start, num_planes); - - gen_steps(attribs_begin, attribs_end, attribs_steps, - num_planes, column_delta); + prepare_for_interpolation(left_attribs, rght_attribs, + attribs, column_delta, + n); if (left_boundary < 0) { start_column = 0; span_length += left_boundary; - multi_step_up(attribs_start, attribs_steps, num_planes, - -left_boundary, column_delta); + multi_step_up(attribs, -left_boundary, n); } if (rght_boundary >= fbi->width) { @@ -101,24 +87,17 @@ draw_partial_triangle( } draw_span( - ((bi->start_scanline + row) * fbi->width) + start_column, - span_length, attribs_start, attribs_steps, column_delta, - fbi); + (bi->start_scanline + row) * fbi->width + start_column, + span_length, attribs, fbi); if (row_delta > 0) { - step_up(left_attribs, left_attribs_steps, num_planes, - left_div); - step_up(rght_attribs, rght_attribs_steps, num_planes, - rght_div); + step_up(left_attribs, n); + step_up(rght_attribs, n); } - row++; - free(attribs_steps); - free(attribs_end); - free(attribs_begin); - free(attribs_start); } } } + free(attribs); free(rght_attribs); free(left_attribs); } @@ -127,31 +106,19 @@ draw_partial_triangle( static void draw_degenerate_horizontal(Xy const xy, - fract * const attribs_left, - fract * const attribs_mid, - const fract * const top2mid_steps, - const fract * const top2bot_steps, - const fract * const mid2bot_steps, - int32_t const top2mid_delta, - int32_t const top2bot_delta, - int32_t const mid2bot_delta, + varying * const top2mid, + varying * const top2bot, + varying * const mid2bot, framebuffer_info * const fbi) { - uint8_t const num_planes = fbi->num_attribs + 1; - - fract * attribs_left_bkup; - - MALLOCARRAY_NOFAIL(attribs_left_bkup, num_planes); - - memcpy(attribs_left_bkup, attribs_left, num_planes * sizeof(fract)); + uint8_t const n = fbi->num_attribs + 2; { int16_t const y = xy._[0][1]; int16_t x[3]; int16_t x_start[3]; - fract * attribs[3]; - const fract * steps[3]; + varying * attribs[3]; int32_t span_length[3]; unsigned int i; @@ -163,28 +130,21 @@ draw_degenerate_horizontal(Xy const xy, x_start[1] = x[0]; x_start[2] = x[1]; - attribs[0] = attribs_left; - attribs[1] = attribs_left_bkup; - attribs[2] = attribs_mid; - - steps[0] = top2bot_steps; - steps[1] = top2mid_steps; - steps[2] = mid2bot_steps; + attribs[0] = top2bot; + attribs[1] = top2mid; + attribs[2] = mid2bot; span_length[0] = x[2] - x[0]; span_length[1] = x[1] - x[0]; span_length[2] = x[2] - x[1]; for (i = 0; i < 3; i++) { - int32_t const column_delta = span_length[i]; - if (x_start[i] >= fbi->width || x_start[i] + span_length[i] < 0) { continue; } if (x_start[i] < 0) { - multi_step_up(attribs[i], steps[i], num_planes, -x_start[i], - column_delta); + multi_step_up(attribs[i], -x_start[i], n); span_length[i] += x_start[i]; @@ -197,11 +157,10 @@ draw_degenerate_horizontal(Xy const xy, span_length[i]++; } - draw_span((y * fbi->width) + x_start[i], span_length[i], - attribs[i], steps[i], column_delta, fbi); + draw_span(y * fbi->width + x_start[i], span_length[i], + attribs[i], fbi); } } - free(attribs_left_bkup); } @@ -212,23 +171,28 @@ draw_triangle(Xy const xy_input, boundary_info * const bi, framebuffer_info * const fbi) { - uint8_t const num_planes = fbi->num_attribs + 1; + uint8_t const z = fbi->num_attribs; + uint8_t const w = z + 1; + uint8_t const n = w + 1; Xy xy; - int32_t * attribs[3]; + varying * attribs[3]; unsigned int i; uint8_t index_array[3]; int32_t y_array[3]; int32_t x_array[3]; - MALLOCARRAY_NOFAIL(attribs[0], num_planes); - MALLOCARRAY_NOFAIL(attribs[1], num_planes); - MALLOCARRAY_NOFAIL(attribs[2], num_planes); + MALLOCARRAY_NOFAIL(attribs[0], n); + MALLOCARRAY_NOFAIL(attribs[1], n); + MALLOCARRAY_NOFAIL(attribs[2], n); xy = xy_input; for (i = 0; i < 3; i++) { - memcpy(attribs[i], attribs_input._[i], num_planes * sizeof(int32_t)); + int32_to_varying_array(attribs_input._[i], attribs[i], n); + attribs[i][z] = compute_varying_z(attribs_input._[i][z]); + attribs[i][w] = inverse_varying(attribs[i][w]); + multiply_varying_array_by_varying(attribs[i], attribs[i][w], z); } /* Argument preparations for sort3: */ @@ -259,122 +223,65 @@ draw_triangle(Xy const xy_input, gen_triangle_boundaries(xy_sorted, bi, fbi->width, fbi->height); if (bi->start_scanline == -1) { - /* Triangle is completely out of the bounds of the framebuffer. */ + /* Triangle is completely out of the bounds of the frame buffer. */ } else { bool const no_upper_part = (xy_sorted._[1][1] == xy_sorted._[0][1]); bool const horizontal = (xy._[0][1] == xy._[1][1] && xy._[1][1] == xy._[2][1]); - /* We are dealing with a degenerate horizontal triangle */ + /* Tells whether we are dealing with a degenerate + * horizontal triangle */ - uint8_t t = ~horizontal & 1; + uint8_t const t = horizontal ^ 1; int32_t top2mid_delta = xy._[mid][t] - xy._[top][t]; int32_t top2bot_delta = xy._[bot][t] - xy._[top][t]; int32_t mid2bot_delta = xy._[bot][t] - xy._[mid][t]; - fract * top2mid_steps; - fract * top2bot_steps; - fract * mid2bot_steps; + varying * top2mid; + varying * top2bot; + varying * mid2bot; - fract * upper_left_attribs_steps; - fract * lower_left_attribs_steps; - fract * upper_rght_attribs_steps; - fract * lower_rght_attribs_steps; + varying * upper_left_attribs; + varying * lower_left_attribs; + varying * upper_rght_attribs; + varying * lower_rght_attribs; - int32_t upper_left_delta; - int32_t lower_left_delta; - int32_t upper_rght_delta; - int32_t lower_rght_delta; + MALLOCARRAY_NOFAIL(top2mid, n); + MALLOCARRAY_NOFAIL(top2bot, n); + MALLOCARRAY_NOFAIL(mid2bot, n); - fract * left_attribs; - fract * rght_attribs; - - bool degenerate_horizontal; - - MALLOCARRAY_NOFAIL(top2mid_steps, num_planes); - MALLOCARRAY_NOFAIL(top2bot_steps, num_planes); - MALLOCARRAY_NOFAIL(mid2bot_steps, num_planes); - MALLOCARRAY_NOFAIL(left_attribs, num_planes); - MALLOCARRAY_NOFAIL(rght_attribs, num_planes); - - if (!horizontal) { - top2mid_delta += !no_upper_part; - top2bot_delta += 1; - mid2bot_delta += no_upper_part; - } - - gen_steps(attribs[top], attribs[mid], top2mid_steps, num_planes, - top2mid_delta); - gen_steps(attribs[top], attribs[bot], top2bot_steps, num_planes, - top2bot_delta); - gen_steps(attribs[mid], attribs[bot], mid2bot_steps, num_planes, - mid2bot_delta); - - int32_to_fract_array(attribs[top], left_attribs, num_planes); - int32_to_fract_array(attribs[top], rght_attribs, num_planes); + prepare_for_interpolation(attribs[top], attribs[mid], top2mid, top2mid_delta, n); + prepare_for_interpolation(attribs[top], attribs[bot], top2bot, top2bot_delta, n); + prepare_for_interpolation(attribs[mid], attribs[bot], mid2bot, mid2bot_delta, n); if (mid_is_to_the_left) { - upper_left_attribs_steps = top2mid_steps; - lower_left_attribs_steps = mid2bot_steps; - upper_rght_attribs_steps = top2bot_steps; - lower_rght_attribs_steps = upper_rght_attribs_steps; - - upper_left_delta = top2mid_delta; - lower_left_delta = mid2bot_delta; - upper_rght_delta = top2bot_delta; - lower_rght_delta = upper_rght_delta; + upper_left_attribs = top2mid; + lower_left_attribs = mid2bot; + upper_rght_attribs = top2bot; + lower_rght_attribs = upper_rght_attribs; } else { - upper_rght_attribs_steps = top2mid_steps; - lower_rght_attribs_steps = mid2bot_steps; - upper_left_attribs_steps = top2bot_steps; - lower_left_attribs_steps = upper_left_attribs_steps; - - upper_rght_delta = top2mid_delta; - lower_rght_delta = mid2bot_delta; - upper_left_delta = top2bot_delta; - lower_left_delta = upper_left_delta; + upper_rght_attribs = top2mid; + lower_rght_attribs = mid2bot; + upper_left_attribs = top2bot; + lower_left_attribs = upper_left_attribs; } - if (no_upper_part) { - int32_to_fract_array(attribs[mid], rght_attribs, num_planes); - - if (horizontal) { - degenerate_horizontal = true; - } else { - degenerate_horizontal = false; - - step_up(left_attribs, lower_left_attribs_steps, num_planes, - lower_left_delta); - step_up(rght_attribs, lower_rght_attribs_steps, num_planes, - lower_rght_delta); - } - } else { + if (!(horizontal || no_upper_part)) { int32_t delta; - degenerate_horizontal = false; - - step_up(left_attribs, upper_left_attribs_steps, num_planes, - upper_left_delta); - step_up(rght_attribs, upper_rght_attribs_steps, num_planes, - upper_rght_delta); - if (bi->num_upper_rows > 0) { - if (bi->start_scanline > xy._[top][1]) { delta = bi->start_scanline - xy._[top][1]; - multi_step_up(left_attribs, upper_left_attribs_steps, - num_planes, delta, upper_left_delta); - multi_step_up(rght_attribs, upper_rght_attribs_steps, - num_planes, delta, upper_rght_delta); + multi_step_up(upper_left_attribs, delta, n); + multi_step_up(upper_rght_attribs, delta, n); } draw_partial_triangle( - left_attribs, upper_left_attribs_steps, - rght_attribs, upper_rght_attribs_steps, - upper_left_delta, upper_rght_delta, + upper_left_attribs, + upper_rght_attribs, true, bi, fbi @@ -385,40 +292,33 @@ draw_triangle(Xy const xy_input, delta = top2mid_delta; } - multi_step_up(left_attribs, upper_left_attribs_steps, - num_planes, delta, upper_left_delta); - multi_step_up(rght_attribs, upper_rght_attribs_steps, - num_planes, delta, upper_rght_delta); + multi_step_up(upper_left_attribs, delta, n); + multi_step_up(upper_rght_attribs, delta, n); } - if (degenerate_horizontal) { + + if (horizontal) { draw_degenerate_horizontal( xy_sorted, - left_attribs, rght_attribs, - top2mid_steps, top2bot_steps, mid2bot_steps, - top2mid_delta, top2bot_delta, mid2bot_delta, + top2mid, top2bot, mid2bot, fbi ); } else { if (bi->start_scanline > xy._[mid][1]) { int32_t const delta = bi->start_scanline - xy._[mid][1]; - multi_step_up(left_attribs, lower_left_attribs_steps, - num_planes, delta, lower_left_delta); - multi_step_up(rght_attribs, lower_rght_attribs_steps, - num_planes, delta, lower_rght_delta); + multi_step_up(lower_left_attribs, delta, n); + multi_step_up(lower_rght_attribs, delta, n); } draw_partial_triangle( - left_attribs, lower_left_attribs_steps, - rght_attribs, lower_rght_attribs_steps, - lower_left_delta, lower_rght_delta, + lower_left_attribs, + lower_rght_attribs, false, bi, fbi ); } - free(rght_attribs); free(left_attribs); - free(mid2bot_steps); free(top2bot_steps); free(top2mid_steps); + free(mid2bot); free(top2bot); free(top2mid); } } free(attribs[2]); free(attribs[1]); free(attribs[0]); |