// license:BSD-3-Clause
// copyright-holders:Ville Linde, Aaron Giles
/***************************************************************************
polylgcy.h
Legacy polygon helper routines.
****************************************************************************
Pixel model:
(0.0,0.0) (1.0,0.0) (2.0,0.0) (3.0,0.0)
+---------------+---------------+---------------+
| | | |
| | | |
| (0.5,0.5) | (1.5,0.5) | (2.5,0.5) |
| * | * | * |
| | | |
| | | |
(0.0,1.0) (1.0,1.0) (2.0,1.0) (3.0,1.0)
+---------------+---------------+---------------+
| | | |
| | | |
| (0.5,1.5) | (1.5,1.5) | (2.5,1.5) |
| * | * | * |
| | | |
| | | |
| | | |
+---------------+---------------+---------------+
(0.0,2.0) (1.0,2.0) (2.0,2.0) (3.0,2.0)
***************************************************************************/
#ifndef MAME_VIDEO_POLYLGCY_H
#define MAME_VIDEO_POLYLGCY_H
#pragma once
/***************************************************************************
CONSTANTS
***************************************************************************/
static constexpr unsigned POLYLGCY_MAX_VERTEX_PARAMS = 6;
static constexpr unsigned POLYLGCY_MAX_POLYGON_VERTS = 32;
static constexpr uint8_t POLYLGCY_FLAG_INCLUDE_BOTTOM_EDGE = 0x01;
static constexpr uint8_t POLYLGCY_FLAG_INCLUDE_RIGHT_EDGE = 0x02;
static constexpr uint8_t POLYLGCY_FLAG_NO_WORK_QUEUE = 0x04;
static constexpr uint8_t POLYLGCY_FLAG_ALLOW_QUADS = 0x08;
/***************************************************************************
TYPE DEFINITIONS
***************************************************************************/
/* opaque reference to the poly manager */
struct legacy_poly_manager;
/* input vertex data */
struct poly_vertex
{
float x; /* X coordinate */
float y; /* Y coordinate */
float p[POLYLGCY_MAX_VERTEX_PARAMS]; /* interpolated parameter values */
};
/* poly_param_extent describes information for a single parameter in an extent */
struct poly_param_extent
{
float start; /* parameter value at starting X,Y */
float dpdx; /* dp/dx relative to starting X */
};
/* poly_extent describes start/end points for a scanline, along with per-scanline parameters */
struct poly_extent
{
int16_t startx; /* starting X coordinate (inclusive) */
int16_t stopx; /* ending X coordinate (exclusive) */
poly_param_extent param[POLYLGCY_MAX_VERTEX_PARAMS]; /* starting and dx values for each parameter */
};
/* callback routine to process a batch of scanlines in a triangle */
typedef void (*poly_draw_scanline_func)(void *dest, int32_t scanline, const poly_extent *extent, const void *extradata, int threadid);
/***************************************************************************
TYPE DEFINITIONS
***************************************************************************/
/* ----- initialization/teardown ----- */
/* allocate a new poly manager that can render triangles */
legacy_poly_manager *poly_alloc(running_machine &machine, int max_polys, size_t extra_data_size, uint8_t flags);
/* free a poly manager */
void poly_free(legacy_poly_manager *poly);
/* ----- common functions ----- */
/* wait until all polygons in the queue have been rendered */
void poly_wait(legacy_poly_manager *poly, const char *debug_reason);
/* get a pointer to the extra data for the next polygon */
void *poly_get_extra_data(legacy_poly_manager *poly);
/* ----- core triangle rendering ----- */
/* render a single triangle given 3 vertexes */
uint32_t poly_render_triangle(legacy_poly_manager *poly, void *dest, const rectangle &cliprect, poly_draw_scanline_func callback, int paramcount, const poly_vertex *v1, const poly_vertex *v2, const poly_vertex *v3);
/* render a set of triangles in a fan */
uint32_t poly_render_triangle_fan(legacy_poly_manager *poly, void *dest, const rectangle &cliprect, poly_draw_scanline_func callback, int paramcount, int numverts, const poly_vertex *v);
/* perform a custom render of an object, given specific extents */
uint32_t poly_render_triangle_custom(legacy_poly_manager *poly, void *dest, const rectangle &cliprect, poly_draw_scanline_func callback, int startscanline, int numscanlines, const poly_extent *extents);
/* ----- core quad rendering ----- */
/* render a single quad given 4 vertexes */
uint32_t poly_render_quad(legacy_poly_manager *poly, void *dest, const rectangle &cliprect, poly_draw_scanline_func callback, int paramcount, const poly_vertex *v1, const poly_vertex *v2, const poly_vertex *v3, const poly_vertex *v4);
/* render a set of quads in a fan */
uint32_t poly_render_quad_fan(legacy_poly_manager *poly, void *dest, const rectangle &cliprect, poly_draw_scanline_func callback, int paramcount, int numverts, const poly_vertex *v);
/* ----- core polygon rendering ----- */
/* render a single polygon up to 32 vertices */
uint32_t poly_render_polygon(legacy_poly_manager *poly, void *dest, const rectangle &cliprect, poly_draw_scanline_func callback, int paramcount, int numverts, const poly_vertex *v);
/* ----- clipping ----- */
/* zclip (assumes p[0] == z) a polygon */
int poly_zclip_if_less(int numverts, const poly_vertex *v, poly_vertex *outv, int paramcount, float clipval);
#endif // MAME_VIDEO_POLYLGCY_H