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Add presets

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Miloslav Číž 2019-05-28 19:14:27 +02:00
parent 240119353e
commit e7dc709ebd
3 changed files with 107 additions and 96 deletions
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191
small3dlib.h
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@ -113,6 +113,61 @@
#include <stdint.h> #include <stdint.h>
// values for setting the library behavior:
#define S3L_Z_BUFFER_NONE 0 /**< Don't use z-buffer. This saves a lot of
memory, but visibility checking won't be
pixel-accurate and has to mostly be done by
other means (typically sorting). */
#define S3L_Z_BUFFER_FULL 1 /**< Use full z-buffer (of S3L_Units) for
visibiltiy determination. This is the most
accurate option (and also a fast one), but
requires a big amount of memory. */
#define S3L_Z_BUFFER_BYTE 2 /**< Use reduced-size z-buffer (of bytes). This is
fast and somewhat accurate, but inaccuracies
can occur and a considerable amount of memory
is needed. */
#define S3L_SORT_NONE 0 /**< Don't sort triangles. This is fastest. */
#define S3L_SORT_BACK_TO_FRONT 1 /**< Sort triangles from back to front. This
can in most cases solve visibility without
requiring almost any extra memory compared to
z-buffer. */
#define S3L_SORT_FRONT_TO_BACK 2 /**< Sort triangles from front to back. This
can be faster than back to front, because we
prevent computing pixels that will be
overwritten by nearer ones, but we need a 1b
stencil buffer for this (enable
S3L_STENCIL_BUFFER), so a bit more memory is
needed. */
#define S3L_PC_NONE 0 /**< No perspective correction. Fastest, ugly. */
#define S3L_PC_FULL 1 /**< Per-pixel perspective correction, nice but
very expensive. */
#define S3L_PC_SUBDIVIDE 2 /**< Partial perspecive correction by subdividing
triangles. */
/* === PRESETS ===
These can be used to quickly set a predefined library behavior.
*/
#ifdef S3L_PRESET_HIGHEST_QUALITY
#define S3L_Z_BUFFER S3L_Z_BUFFER_FULL
#define S3L_PERSPECTIVE_CORRECTION S3L_PC_FULL
#define S3L_NEAR_CLAMPING 1
#endif
#ifdef S3L_PRESET_EMBEDDED
#define S3L_Z_BUFFER S3L_Z_BUFFER_NONE
#define S3L_PERSPECTIVE_CORRECTION 0
#define S3L_NEAR_CLAMPING 0
#define S3L_SORT S3L_SORT_BACK_TO_FRONT
#define S3L_STENCIL_BUFFER 0
#define S3L_MAX_TRIANGES_DRAWN 64
#endif
// ---------------
#ifndef S3L_RESOLUTION_X #ifndef S3L_RESOLUTION_X
#define S3L_RESOLUTION_X 640 ///< Redefine to your screen x resolution. #define S3L_RESOLUTION_X 640 ///< Redefine to your screen x resolution.
#endif #endif
@ -122,68 +177,47 @@
#endif #endif
#ifndef S3L_COMPUTE_DEPTH #ifndef S3L_COMPUTE_DEPTH
#define S3L_COMPUTE_DEPTH 0 /**< Whether to compute depth for each pixel #define S3L_COMPUTE_DEPTH 0 /**< Whether to compute depth for each pixel
(fragment). Some other options may turn this (fragment). Some other options may turn this
on. */ on. */
#endif #endif
#ifndef S3L_NEAR_CLAMPING #ifndef S3L_NEAR_CLAMPING
#define S3L_NEAR_CLAMPING 0 /**< Whether to use depth clamping for the near #define S3L_NEAR_CLAMPING 0 /**< Whether to use depth clamping for the near
plane. Only works with S3L_COMPUTE_DEPTH plane. Only works with S3L_COMPUTE_DEPTH
enabled! This may be a bit slower, but can enabled! This may be a bit slower, but can
prevent errorneous rendering in specific cases prevent errorneous rendering in specific
and is closer to traditional 3D engines. */ cases and is closer to traditional 3D
engines. */
#endif #endif
#ifndef S3L_PERSPECTIVE_CORRECTION #ifndef S3L_PERSPECTIVE_CORRECTION
#define S3L_PERSPECTIVE_CORRECTION 0 /**< Specifies what type of perspective #define S3L_PERSPECTIVE_CORRECTION 0 /**< Specifies what type of perspective
correction (PC) to use. Remember correction (PC) to use. Remember this is an
this is an expensive operation! expensive operation! See S3L_PC_*. */
Possible values:
0: no PC, fastest but ugliest
1: full (per-pixel) PC, nicest but
extremely expensive!
2: triangle subdivided PC, a
compromise between quality and
speed (TODO, not implemented)
*/
#endif #endif
typedef int32_t S3L_Unit; /**< Units of measurement in 3D space. There is typedef int32_t S3L_Unit; /**< Units of measurement in 3D space. There is
S3L_FRACTIONS_PER_UNIT in one spatial unit. S3L_FRACTIONS_PER_UNIT in one spatial unit.
By dividing the unit into fractions we By dividing the unit into fractions we
effectively achieve fixed point arithmetic. effectively achieve fixed point arithmetic.
The number of fractions is a constant that The number of fractions is a constant that
serves as 1.0 in floating point arithmetic serves as 1.0 in floating point arithmetic
(normalization etc.). */ (normalization etc.). */
#define S3L_FRACTIONS_PER_UNIT 512 /**< How many fractions a spatial unit is #define S3L_FRACTIONS_PER_UNIT 512 /**< How many fractions a spatial unit is
split into. WARNING: if setting split into. WARNING: if setting higher than
higher than 1024, you'll probably 1024, you'll probably have to modify a sin
have to modify a sin table otherwise table otherwise it will overflow. Also other
it will overflow. Also other things things may overflow, so rather don't do
may overflow, so rather don't do it. */ it. */
typedef int16_t S3L_ScreenCoord; typedef int16_t S3L_ScreenCoord;
typedef uint16_t S3L_Index; typedef uint16_t S3L_Index;
#define S3L_Z_BUFFER_NONE 0 /**< Don't use z-buffer. This saves a lot of
memory, but visibility checking won't be
pixel-accurate and has to mostly be done by
other means (typically sorting). */
#define S3L_Z_BUFFER_FULL 1 /**< Use full z-buffer (of S3L_Units) for
visibiltiy determination. This is the most
accurate option (and also a fast one), but
requires a big amount of memory. */
#define S3L_Z_BUFFER_BYTE 2 /**< Use reduced-size z-buffer (of bytes). This is
fast and somewhat accurate, but inaccuracies
can occur and a considerable amount of memory
is needed. */
#ifndef S3L_Z_BUFFER #ifndef S3L_Z_BUFFER
#define S3L_Z_BUFFER S3L_Z_BUFFER_NONE /**< What type of z-buffer (depth #define S3L_Z_BUFFER S3L_Z_BUFFER_NONE /**< What type of z-buffer (depth
buffer) to use for visibility buffer) to use for visibility determination.
determination. See See S3L_Z_BUFFER_*. */
S3L_Z_BUFFER_*. */
#endif #endif
#ifndef S3L_STENCIL_BUFFER #ifndef S3L_STENCIL_BUFFER
@ -193,53 +227,38 @@ typedef uint16_t S3L_Index;
for front-to-back sorted drawing. */ for front-to-back sorted drawing. */
#endif #endif
#define S3L_SORT_NONE 0 /**< Don't sort triangles. This is fastest. */
#define S3L_SORT_BACK_TO_FRONT 1 /**< Sort triangles from back to front. This
can in most cases solve visibility
without requiring almost any extra
memory compared to z-buffer. */
#define S3L_SORT_FRONT_TO_BACK 2 /**< Sort triangles from front to back. This
can be faster than back to front, because
we prevent computing pixels that will be
overwritten by nearer ones, but we need
a 1b stencil buffer for this (enable
S3L_STENCIL_BUFFER), so a bit more memory
is needed. */
#ifndef S3L_SORT #ifndef S3L_SORT
#define S3L_SORT S3L_SORT_NONE /**< Defines how to sort triangles before #define S3L_SORT S3L_SORT_NONE /**< Defines how to sort triangles before
drawing a frame. This can be used to solve drawing a frame. This can be used to solve
visibility in case z-buffer is not used, to visibility in case z-buffer is not used, to
prevent overwrting already rasterized prevent overwrting already rasterized pixels,
pixels, implement transparency etc. Note implement transparency etc. Note that for
that for simplicity and performance a simplicity and performance a relatively
relatively simple sorting is used which simple sorting is used which doesn't work
doesn't work completely correctly, so completely correctly, so mistakes can occur
mistakes can occur (even the best sorting (even the best sorting wouldn't be able to
wouldn't be able to solve e.g. intersecting solve e.g. intersecting triangles). */
triangles). */
#endif #endif
#ifndef S3L_MAX_TRIANGES_DRAWN #ifndef S3L_MAX_TRIANGES_DRAWN
#define S3L_MAX_TRIANGES_DRAWN 128 /**< Maximum number of triangles that can #define S3L_MAX_TRIANGES_DRAWN 128 /**< Maximum number of triangles that can be
be drawn in sorted modes. This drawn in sorted modes. This affects the size
affects the size of a cache used for of a cache used for triangle sorting. */
triangle sorting. */
#endif #endif
#ifndef S3L_NEAR #ifndef S3L_NEAR
#define S3L_NEAR (S3L_FRACTIONS_PER_UNIT / 4) /**< Distance of the near #define S3L_NEAR (S3L_FRACTIONS_PER_UNIT / 4) /**< Distance of the near
clipping plane. */ clipping plane. */
#endif #endif
#ifndef S3L_FAST_LERP_QUALITY #ifndef S3L_FAST_LERP_QUALITY
#define S3L_FAST_LERP_QUALITY 8 /**< Quality (scaling) of SOME linear #define S3L_FAST_LERP_QUALITY 8 /**< Quality (scaling) of SOME linear
interpolations. 0 will most likely be interpolations. 0 will most likely be faster,
faster, but artifacts can occur for but artifacts can occur for bigger tris,
bigger tris, while higher values can fix while higher values can fix this -- in
this -- in theory all higher values will theory all higher values will have the same
have the same speed (it is a shift speed (it is a shift value), but it mustn't
value), but it mustn't be too high to be too high to prevent overflow. */
prevent overflow. */
#endif #endif
#define S3L_HALF_RESOLUTION_X (S3L_RESOLUTION_X >> 1) #define S3L_HALF_RESOLUTION_X (S3L_RESOLUTION_X >> 1)
@ -304,11 +323,8 @@ typedef uint16_t S3L_Index;
0,m, m,0, m,m,\ 0,m, m,0, m,m,\
0,m, 0,0, m,0 0,m, 0,0, m,0
/** /** Vector that consists of four scalars and can represent homogenous
Vector that consists of four scalars and can represent homogenous coordinates, but is generally also used as Vec3 and Vec2. */
coordinates, but is generally also used as Vec3 and Vec2.
*/
typedef struct typedef struct
{ {
S3L_Unit x; S3L_Unit x;
@ -338,8 +354,7 @@ typedef struct
static inline void S3L_initTransoform3D(S3L_Transform3D *t); static inline void S3L_initTransoform3D(S3L_Transform3D *t);
/** Converts rotation transformation to three direction vectors of given length /** Converts rotation transformation to three direction vectors of given length
(any one can be NULL, in which case it won't be computed). (any one can be NULL, in which case it won't be computed). */
*/
void S3L_rotationToDirections( void S3L_rotationToDirections(
S3L_Vec4 rotation, S3L_Vec4 rotation,
S3L_Unit length, S3L_Unit length,

6
testSDL.c
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@ -7,11 +7,7 @@
#include <stdio.h> #include <stdio.h>
#include <math.h> #include <math.h>
#define S3L_Z_BUFFER 0 #define S3L_PRESET_EMBEDDED
#define S3L_STENCIL_BUFFER 1
#define S3L_SORT S3L_SORT_FRONT_TO_BACK
#define S3L_PIXEL_FUNCTION drawPixel #define S3L_PIXEL_FUNCTION drawPixel

6
todo.txt
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@ -1,8 +1,8 @@
features: features:
- scene and model rendering strategies, that can be optionally selected and - presets that can be optionally selected and will configure other constants
will configure other constants (e.g. a "low memory sort strategy" will turn (e.g. a "low memory sort strategy" will turn z-buffer off and turn
z-buffer off and turn back-to-front sorting on). back-to-front sorting on).
- triangle sorting: - triangle sorting:
- back-to-front (slower, better memory efficiency) - back-to-front (slower, better memory efficiency)