geometry.h File Reference

#include "math/math_types.h"
#include "strings/kname.h"

Go to the source code of this file.

Data Structures
struct	kgeometry
	Represents geometry to be used for various purposes (rendering objects in the world, physics/collision, etc.). More...

Macros
#define	GEOMETRY_NAME_MAX_LENGTH   256
	The maximum length of a geometry name. More...

Typedefs
typedef enum kgeometry_type	kgeometry_type
	Indicates a geometry type, typically used to infer things like vertex and index sizes. More...
typedef struct kgeometry	kgeometry
	Represents geometry to be used for various purposes (rendering objects in the world, physics/collision, etc.). More...
typedef enum grid_orientation	grid_orientation

Enumerations
enum	kgeometry_type {   KGEOMETRY_TYPE_UNKNOWN = 0x00 , KGEOMETRY_TYPE_2D_STATIC = 0x01 , KGEOMETRY_TYPE_2D_DYNAMIC = 0x02 , KGEOMETRY_TYPE_3D_STATIC = 0x03 ,   KGEOMETRY_TYPE_3D_STATIC_COLOUR_ONLY = 0x04 , KGEOMETRY_TYPE_3D_DYNAMIC = 0x05 , KGEOMETRY_TYPE_3D_SKINNED = 0x06 , KGEOMETRY_TYPE_3D_HEIGHTMAP_TERRAIN = 0x07 ,   KGEOMETRY_TYPE_CUSTOM = 0xFF }
	Indicates a geometry type, typically used to infer things like vertex and index sizes. More...
enum	grid_orientation { GRID_ORIENTATION_XZ = 0 , GRID_ORIENTATION_XY = 1 , GRID_ORIENTATION_YZ = 2 }

Functions
KAPI void	geometry_generate_normals (u32 vertex_count, vertex_3d *vertices, u32 index_count, u32 *indices)
	Calculates normals for the given vertex and index data. Modifies vertices in place. More...
KAPI void	geometry_generate_tangents (u32 vertex_count, vertex_3d *vertices, u32 index_count, u32 *indices)
	Calculates tangents for the given vertex and index data. Modifies vertices in place. More...
KAPI void	geometry_deduplicate_vertices (u32 vertex_count, vertex_3d *vertices, u32 index_count, u32 *indices, u32 *out_vertex_count, vertex_3d **out_vertices)
	De-duplicates vertices, leaving only unique ones. Leaves the original vertices array intact. Allocates a new array in out_vertices. Modifies indices in-place. Original vertex array should be freed by caller. More...
KAPI void	generate_uvs_from_image_coords (u32 img_width, u32 img_height, u32 px_x, u32 px_y, f32 *out_tx, f32 *out_ty)
	Generates texture coordinates based on pixel position within an image's dimensions. More...
KAPI kgeometry	geometry_generate_quad (f32 width, f32 height, f32 tx_min, f32 tx_max, f32 ty_min, f32 ty_max, kname name)
	Generates a two-dimensional quad (two triangles) of geometry. Note that memory for the vertex and index arrays are dynamically allocated, so this should be cleaned up with geometry_destroy(). Dimensions account for the x- and y-axes only. More...
KAPI kgeometry	geometry_generate_line2d (vec2 point_0, vec2 point_1, kname name)
	Generates a two-dimensional line of geometry. Note that the memory for the vertex array is dynamically allocated, so this should be cleaned up with geometry_destroy(). Note that index data is not used for this geometry. More...
KAPI kgeometry	geometry_generate_line3d (vec3 point_0, vec3 point_1, kname name)
	Generates a three-dimensional line of geometry. Note that the memory for the vertex array is dynamically allocated, so this should be cleaned up with geometry_destroy(). Note that index data is not used for this geometry. More...
KAPI kgeometry	geometry_generate_line_sphere3d (f32 radius, u32 segment_count, vec4 colour, kname name)
KAPI kgeometry	geometry_generate_plane (f32 width, f32 height, u32 x_segment_count, u32 y_segment_count, f32 tile_x, f32 tile_y, kname name)
	Generates a three-dimensional plane of geometry. Note that memory for the vertex and index arrays are dynamically allocated, so this should be cleaned up with geometry_destroy(). Dimensions account for the x- and y-axes, z is always 0. More...
KAPI void	geometry_recalculate_line_box3d_by_points (kgeometry *geometry, vec3 points[8])
	Recalculates the vertices in the given geometry based off the given points. More...
KAPI void	geometry_recalculate_line_box3d_by_extents (kgeometry *geometry, extents_3d extents)
	Recalculates the vertices in the given geometry based off the given extents. More...
KAPI kgeometry	geometry_generate_line_box3d (vec3 size, kname name)
	Generates a line-based 3d box based on the provided size. More...
KAPI kgeometry	geometry_generate_cube (f32 width, f32 height, f32 depth, f32 tile_x, f32 tile_y, kname name)
	Generates a three-dimensional cube of geometry. Note that memory for the vertex and index arrays are dynamically allocated, so this should be cleaned up with geometry_destroy(). More...
KAPI kgeometry	geometry_generate_grid (grid_orientation orientation, u32 segment_count_dim_0, u32 segment_count_dim_1, f32 segment_size, b8 use_third_axis, kname name)
	Create a geometry-based grid using the given parameters. The grid is based on line geometry and has no indices. Note that the vertex array data is dynamically allocated and should be cleaned up using geometry_destroy(). More...
KAPI void	geometry_destroy (kgeometry *geometry)
	Destroys the given geometry. More...

Macro Definition Documentation

GEOMETRY_NAME_MAX_LENGTH

#define GEOMETRY_NAME_MAX_LENGTH   256

The maximum length of a geometry name.

Typedef Documentation

grid_orientation

typedef enum grid_orientation grid_orientation

kgeometry

typedef struct kgeometry kgeometry

Represents geometry to be used for various purposes (rendering objects in the world, physics/collision, etc.).

kgeometry_type

typedef enum kgeometry_type kgeometry_type

Indicates a geometry type, typically used to infer things like vertex and index sizes.

Enumeration Type Documentation

grid_orientation

enum grid_orientation

Enumerator
GRID_ORIENTATION_XZ	A grid that lies "flat" in the world along the ground plane (y-plane). This is the default configuration.
GRID_ORIENTATION_XY	A grid that lies on the z-plane (facing the screen by default, orthogonal to the ground plane).
GRID_ORIENTATION_YZ	A grid that lies on the x-plane (orthogonal to the default screen plane and the ground plane).

kgeometry_type

enum kgeometry_type

Indicates a geometry type, typically used to infer things like vertex and index sizes.

Enumerator
KGEOMETRY_TYPE_UNKNOWN	Unknown and invalid type of geometry. This being set generally indicates an error in code.
KGEOMETRY_TYPE_2D_STATIC	Used for 2d geometry that doesn't change.
KGEOMETRY_TYPE_2D_DYNAMIC	Used for 2d geometry that changes often.
KGEOMETRY_TYPE_3D_STATIC	Used for 3d geometry that doesn't change.
KGEOMETRY_TYPE_3D_STATIC_COLOUR_ONLY	Used for 3d geometry that doesn't change, and only contains colour data.
KGEOMETRY_TYPE_3D_DYNAMIC	Used for 3d geometry that changes often.
KGEOMETRY_TYPE_3D_SKINNED	Used for skinned 3d geometry that changes potentially every frame, and includes bone/weight data.
KGEOMETRY_TYPE_3D_HEIGHTMAP_TERRAIN	Used for heightmap terrain-specific geometry that rarely (if ever) changes - includes material index/weight data.
KGEOMETRY_TYPE_CUSTOM	User-defined geometry type. Vertex/index size will only be looked at for this type.

Function Documentation

generate_uvs_from_image_coords()

KAPI void generate_uvs_from_image_coords	(	u32	img_width,
		u32	img_height,
		u32	px_x,
		u32	px_y,
		f32 *	out_tx,
		f32 *	out_ty
	)

Generates texture coordinates based on pixel position within an image's dimensions.

Parameters

img_width	The width of the image in pixels.
img_height	The height of the image in pixels.
px_x	The pixel position along the x-axis.
px_y	The pixel position along the y-axis.
out_tx	A pointer to hold the generated texture coordinate on the x-axis.
out_ty	A pointer to hold the generated texture coordinate on the y-axis.

geometry_deduplicate_vertices()

KAPI void geometry_deduplicate_vertices	(	u32	vertex_count,
		vertex_3d *	vertices,
		u32	index_count,
		u32 *	indices,
		u32 *	out_vertex_count,
		vertex_3d **	out_vertices
	)

De-duplicates vertices, leaving only unique ones. Leaves the original vertices array intact. Allocates a new array in out_vertices. Modifies indices in-place. Original vertex array should be freed by caller.

Parameters

vertex_count	The number of vertices in the array.
vertices	The original array of vertices to be de-duplicated. Not modified.
index_count	The number of indices in the array.
indices	The array of indices. Modified in-place as vertices are removed.
out_vertex_count	A pointer to hold the final vertex count.
out_vertices	A pointer to hold the array of de-duplicated vertices.

geometry_destroy()

KAPI void geometry_destroy

(

kgeometry *

geometry

)

Destroys the given geometry.

Parameters

geometry

A pointer to the geometry to be destroyed.

geometry_generate_cube()

KAPI kgeometry geometry_generate_cube	(	f32	width,
		f32	height,
		f32	depth,
		f32	tile_x,
		f32	tile_y,
		kname	name
	)

Generates a three-dimensional cube of geometry. Note that memory for the vertex and index arrays are dynamically allocated, so this should be cleaned up with geometry_destroy().

Parameters

width	The width of the cube (x-axis).
height	The height of the cube (y-axis).
depth	The depth of the cube (z-axis).
tile_x	The amount of tiling of the textures on each face of the cube on the x-axis. 1.0 means the texture is stretched across the entire surface. 2.0 means it's repeated, etc.
tile_y	The amount of tiling of the textures on each face of the cube on the y-axis. 1.0 means the texture is stretched across the entire surface. 2.0 means it's repeated, etc.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_grid()

KAPI kgeometry geometry_generate_grid	(	grid_orientation	orientation,
		u32	segment_count_dim_0,
		u32	segment_count_dim_1,
		f32	segment_size,
		b8	use_third_axis,
		kname	name
	)

Create a geometry-based grid using the given parameters. The grid is based on line geometry and has no indices. Note that the vertex array data is dynamically allocated and should be cleaned up using geometry_destroy().

Parameters

orientation	The orientation of the grid.
segment_count_dim_0	The number of segments in the first orientation axis.
segment_count_dim_1	The number of segments in the second orientation axis.
segment_size	The size of each individual segment along all axes.
use_third_axis	Indicates if the grid should also display on a third axis, orthogonal to the two in the orientation.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_line2d()

KAPI kgeometry geometry_generate_line2d	(	vec2	point_0,
		vec2	point_1,
		kname	name
	)

Generates a two-dimensional line of geometry. Note that the memory for the vertex array is dynamically allocated, so this should be cleaned up with geometry_destroy(). Note that index data is not used for this geometry.

Parameters

point_0	The first point of the line.
point_1	The second point of the line.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_line3d()

KAPI kgeometry geometry_generate_line3d	(	vec3	point_0,
		vec3	point_1,
		kname	name
	)

Generates a three-dimensional line of geometry. Note that the memory for the vertex array is dynamically allocated, so this should be cleaned up with geometry_destroy(). Note that index data is not used for this geometry.

Parameters

point_0	The first point of the line.
point_1	The second point of the line.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_line_box3d()

KAPI kgeometry geometry_generate_line_box3d	(	vec3	size,
		kname	name
	)

Generates a line-based 3d box based on the provided size.

Parameters

size	The size (extents) of the box.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_line_sphere3d()

KAPI kgeometry geometry_generate_line_sphere3d	(	f32	radius,
		u32	segment_count,
		vec4	colour,
		kname	name
	)

geometry_generate_normals()

KAPI void geometry_generate_normals	(	u32	vertex_count,
		vertex_3d *	vertices,
		u32	index_count,
		u32 *	indices
	)

Calculates normals for the given vertex and index data. Modifies vertices in place.

Parameters

vertex_count	The number of vertices.
vertices	An array of vertices.
index_count	The number of indices.
indices	An array of vertices.

geometry_generate_plane()

KAPI kgeometry geometry_generate_plane	(	f32	width,
		f32	height,
		u32	x_segment_count,
		u32	y_segment_count,
		f32	tile_x,
		f32	tile_y,
		kname	name
	)

Generates a three-dimensional plane of geometry. Note that memory for the vertex and index arrays are dynamically allocated, so this should be cleaned up with geometry_destroy(). Dimensions account for the x- and y-axes, z is always 0.

Parameters

width	The width of the plane (x-axis).
height	The height of the plane (y-axis).
x_segment_count	The number of segments to split the plane geometry into along the x-axis. Must be at least 1.
y_segment_count	The number of segments to split the plane geometry into along the y-axis. Must be at least 1.
tile_x	The amount of tiling of the textures on the face of the plane on the x-axis. 1.0 means the texture is stretched across the entire surface. 2.0 means it's repeated, etc.
tile_y	The amount of tiling of the textures on the face of the plane on the y-axis. 1.0 means the texture is stretched across the entire surface. 2.0 means it's repeated, etc.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_quad()

KAPI kgeometry geometry_generate_quad	(	f32	width,
		f32	height,
		f32	tx_min,
		f32	tx_max,
		f32	ty_min,
		f32	ty_max,
		kname	name
	)

Generates a two-dimensional quad (two triangles) of geometry. Note that memory for the vertex and index arrays are dynamically allocated, so this should be cleaned up with geometry_destroy(). Dimensions account for the x- and y-axes only.

Parameters

width	The width of the plane (x-axis).
height	The height of the plane (y-axis).
tx_min	The minimum texture coordinate along the x-axis.
ty_min	The minimum texture coordinate along the y-axis.
tx_max	The maximum texture coordinate along the x-axis.
ty_max	The maximum texture coordinate along the y-axis.
name	The name of the geometry.

Returns

The newly-created geometry.

geometry_generate_tangents()

KAPI void geometry_generate_tangents	(	u32	vertex_count,
		vertex_3d *	vertices,
		u32	index_count,
		u32 *	indices
	)

Calculates tangents for the given vertex and index data. Modifies vertices in place.

Parameters

vertex_count	The number of vertices.
vertices	An array of vertices.
index_count	The number of indices.
indices	An array of vertices.

geometry_recalculate_line_box3d_by_extents()

KAPI void geometry_recalculate_line_box3d_by_extents	(	kgeometry *	geometry,
		extents_3d	extents
	)

Recalculates the vertices in the given geometry based off the given extents.

Parameters

geometry	A pointer to the geometry to modify.
extents	The extents of which to base the modification.

geometry_recalculate_line_box3d_by_points()

KAPI void geometry_recalculate_line_box3d_by_points	(	kgeometry *	geometry,
		vec3	points[8]
	)

Recalculates the vertices in the given geometry based off the given points.

Parameters

geometry	A pointer to the geometry to modify.
points	The 8 points (i.e. corners of a box) that will be used for the modification.