/************************************************************************** * * Copyright 2007 VMware, Inc. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * **************************************************************************/ /* Authors: Keith Whitwell */ #include "pipe/p_context.h" #include "pipe/p_defines.h" #include "pipe/p_shader_tokens.h" #include "util/u_math.h" #include "util/u_memory.h" #include "draw_private.h" #include "draw_pipe.h" struct wideline_stage { struct draw_stage stage; float half_line_width; }; static inline struct wideline_stage *wideline_stage( struct draw_stage *stage ) { return (struct wideline_stage *)stage; } /** * Draw a wide line by drawing a quad (two triangles). */ static void wideline_line( struct draw_stage *stage, struct prim_header *header ) { /*const struct wideline_stage *wide = wideline_stage(stage);*/ const unsigned pos = draw_current_shader_position_output(stage->draw); const float half_width = 0.5f * stage->draw->rasterizer->line_width; struct prim_header tri; struct vertex_header *v0 = dup_vert(stage, header->v[0], 0); struct vertex_header *v1 = dup_vert(stage, header->v[0], 1); struct vertex_header *v2 = dup_vert(stage, header->v[1], 2); struct vertex_header *v3 = dup_vert(stage, header->v[1], 3); float *pos0 = v0->data[pos]; float *pos1 = v1->data[pos]; float *pos2 = v2->data[pos]; float *pos3 = v3->data[pos]; const float dx = fabsf(pos0[0] - pos2[0]); const float dy = fabsf(pos0[1] - pos2[1]); const boolean half_pixel_center = stage->draw->rasterizer->half_pixel_center; /* small tweak to meet GL specification */ const float bias = half_pixel_center ? 0.125f : 0.0f; /* * Draw wide line as a quad (two tris) by "stretching" the line along * X or Y. * We need to tweak coords in several ways to be conformant here. */ if (dx > dy) { /* x-major line */ pos0[1] = pos0[1] - half_width - bias; pos1[1] = pos1[1] + half_width - bias; pos2[1] = pos2[1] - half_width - bias; pos3[1] = pos3[1] + half_width - bias; if (half_pixel_center) { if (pos0[0] < pos2[0]) { /* left to right line */ pos0[0] -= 0.5f; pos1[0] -= 0.5f; pos2[0] -= 0.5f; pos3[0] -= 0.5f; } else { /* right to left line */ pos0[0] += 0.5f; pos1[0] += 0.5f; pos2[0] += 0.5f; pos3[0] += 0.5f; } } } else { /* y-major line */ pos0[0] = pos0[0] - half_width + bias; pos1[0] = pos1[0] + half_width + bias; pos2[0] = pos2[0] - half_width + bias; pos3[0] = pos3[0] + half_width + bias; if (half_pixel_center) { if (pos0[1] < pos2[1]) { /* top to bottom line */ pos0[1] -= 0.5f; pos1[1] -= 0.5f; pos2[1] -= 0.5f; pos3[1] -= 0.5f; } else { /* bottom to top line */ pos0[1] += 0.5f; pos1[1] += 0.5f; pos2[1] += 0.5f; pos3[1] += 0.5f; } } } tri.det = header->det; /* only the sign matters */ tri.v[0] = v0; tri.v[1] = v2; tri.v[2] = v3; stage->next->tri( stage->next, &tri ); tri.v[0] = v0; tri.v[1] = v3; tri.v[2] = v1; stage->next->tri( stage->next, &tri ); } static void wideline_first_line( struct draw_stage *stage, struct prim_header *header ) { struct draw_context *draw = stage->draw; struct pipe_context *pipe = draw->pipe; const struct pipe_rasterizer_state *rast = draw->rasterizer; void *r; /* Disable triangle culling, stippling, unfilled mode etc. */ r = draw_get_rasterizer_no_cull(draw, rast->scissor, rast->flatshade); draw->suspend_flushing = TRUE; pipe->bind_rasterizer_state(pipe, r); draw->suspend_flushing = FALSE; stage->line = wideline_line; wideline_line(stage, header); } static void wideline_flush( struct draw_stage *stage, unsigned flags ) { struct draw_context *draw = stage->draw; struct pipe_context *pipe = draw->pipe; stage->line = wideline_first_line; stage->next->flush( stage->next, flags ); /* restore original rasterizer state */ if (draw->rast_handle) { draw->suspend_flushing = TRUE; pipe->bind_rasterizer_state(pipe, draw->rast_handle); draw->suspend_flushing = FALSE; } } static void wideline_reset_stipple_counter( struct draw_stage *stage ) { stage->next->reset_stipple_counter( stage->next ); } static void wideline_destroy( struct draw_stage *stage ) { draw_free_temp_verts( stage ); FREE( stage ); } struct draw_stage *draw_wide_line_stage( struct draw_context *draw ) { struct wideline_stage *wide = CALLOC_STRUCT(wideline_stage); if (!wide) goto fail; wide->stage.draw = draw; wide->stage.name = "wide-line"; wide->stage.next = NULL; wide->stage.point = draw_pipe_passthrough_point; wide->stage.line = wideline_first_line; wide->stage.tri = draw_pipe_passthrough_tri; wide->stage.flush = wideline_flush; wide->stage.reset_stipple_counter = wideline_reset_stipple_counter; wide->stage.destroy = wideline_destroy; if (!draw_alloc_temp_verts( &wide->stage, 4 )) goto fail; return &wide->stage; fail: if (wide) wide->stage.destroy( &wide->stage ); return NULL; }