Blending (The Chickadee Game Toolkit)

From 279f17ac0e1b3d019c2b294098e834d249376686 Mon Sep 17 00:00:00 2001 From: David Thompson Date: Tue, 4 Jun 2019 20:49:16 -0400 Subject: Update chickadee manual. --- manuals/chickadee/API-Reference.html | 4 +- manuals/chickadee/Agendas.html | 31 +- manuals/chickadee/Basics.html | 12 +- manuals/chickadee/Bezier-Curves.html | 22 +- manuals/chickadee/Blending.html | 137 ++++++ manuals/chickadee/Buffers.html | 473 +++++++++++++++++++++ manuals/chickadee/Channels.html | 25 +- manuals/chickadee/Copying-This-Manual.html | 4 +- manuals/chickadee/Easings.html | 47 +- manuals/chickadee/Fonts.html | 84 ++-- manuals/chickadee/Framebuffers.html | 18 +- .../chickadee/GNU-Free-Documentation-License.html | 4 +- manuals/chickadee/Graphics.html | 30 +- manuals/chickadee/Grid.html | 32 +- manuals/chickadee/Index.html | 151 ++++++- manuals/chickadee/Installation.html | 4 +- manuals/chickadee/Kernel.html | 65 ++- manuals/chickadee/Lines-and-Shapes.html | 12 +- manuals/chickadee/Math.html | 4 +- manuals/chickadee/Matrices.html | 38 +- manuals/chickadee/Particles.html | 263 ++++++++++++ manuals/chickadee/Path-Finding.html | 8 +- manuals/chickadee/Quaternions.html | 16 +- manuals/chickadee/Rectangles.html | 83 ++-- manuals/chickadee/Rendering-Engine.html | 62 ++- manuals/chickadee/Requirements.html | 4 +- manuals/chickadee/Scripting.html | 6 +- manuals/chickadee/Scripts.html | 29 +- manuals/chickadee/Shaders.html | 176 +++++++- manuals/chickadee/Sprites.html | 87 ++-- manuals/chickadee/Textures.html | 110 ++++- manuals/chickadee/Tile-Maps.html | 254 ++++++++++- manuals/chickadee/Tweening.html | 6 +- manuals/chickadee/Vectors.html | 90 ++-- manuals/chickadee/Viewports.html | 70 ++- manuals/chickadee/index.html | 43 +- 36 files changed, 2121 insertions(+), 383 deletions(-) create mode 100644 manuals/chickadee/Blending.html create mode 100644 manuals/chickadee/Buffers.html create mode 100644 manuals/chickadee/Particles.html diff --git a/manuals/chickadee/API-Reference.html b/manuals/chickadee/API-Reference.html index d5fdbbe..67d2be0 100644 --- a/manuals/chickadee/API-Reference.html +++ b/manuals/chickadee/API-Reference.html @@ -1,6 +1,6 @@ - diff --git a/manuals/chickadee/Agendas.html b/manuals/chickadee/Agendas.html index eced92c..3580ade 100644 --- a/manuals/chickadee/Agendas.html +++ b/manuals/chickadee/Agendas.html @@ -1,6 +1,6 @@ - @@ -115,11 +117,12 @@ the current time. This is where after comes in handy:

Time units in the agenda are in no way connected to real time. It’s up to the programmer to decide what agenda time means. A simple and -effective approach is to map each call of the update hook +effective approach is to map each call of the update procedure (see Kernel) to 1 unit of agenda time, like so:

(add-hook! update-hook (lambda (dt) (update-agenda 1)))
+(define (update dt)
+  (update-agenda 1))

It is important to call update-agenda periodically, otherwise @@ -147,19 +150,19 @@ scoped and can be changed using the with-agenda special form:

Procedure: agenda? obj
Procedure: agenda? obj: Return #t if obj is an agenda.

Procedure: current-agenda
Procedure: current-agenda agenda
Procedure: current-agenda agenda: When called with no arguments, return the current agenda. When called with one argument, set the current agenda to agenda.

Syntax: with-agenda agenda body …
Syntax: with-agenda agenda body …: Evaluate body with the current agenda set to agenda.

@@ -169,42 +172,42 @@ with one argument, set the current agenda to agenda.

Procedure: update-agenda dt
Procedure: update-agenda dt: Advance the current agenda by dt.

Procedure: schedule-at time thunk
Procedure: schedule-at time thunk: Schedule thunk, a procedure of zero arguments, to be run at time.

Procedure: schedule-after delay thunk
Procedure: schedule-after delay thunk: Schedule thunk, a procedure of zero arguments, to be run after delay.

Procedure: schedule-every interval thunk [n]
Procedure: schedule-every interval thunk [n]: Schedule thunk, a procedure of zero arguments, to be run every interval amount of time. Repeat this n times, or indefinitely if not specified.

Syntax: at time body …
Syntax: at time body …: Schedule body to be evaluated at time.

Syntax: after delay body …
Syntax: after delay body …: Schedule body to be evaluated after delay.

Syntax: every interval body …
Syntax: every (interval n) body …
Syntax: every interval body …
Syntax: every (interval n) body …: Schedule body to be evaluated every interval amount of time. Repeat this n times, or indefinitely if not specified.

diff --git a/manuals/chickadee/Basics.html b/manuals/chickadee/Basics.html index dd3898c..4c2d313 100644 --- a/manuals/chickadee/Basics.html +++ b/manuals/chickadee/Basics.html @@ -1,6 +1,6 @@ - @@ -98,9 +100,9 @@ Next: Vectors, Up: <

Variable: pi: An essential constant for all trigonometry. π is the ratio -of a circle’s circumferences to its diameter. Since π is an -irrational number, the pi in Chickadee is a mere floating point +; An essential constant for all trigonometry. Pi is the ratio of a +circle’s circumferences to its diameter. Since pi is an irrational +number, the pi in Chickadee is a mere floating point approximation that is “good enough.”

@@ -110,7 +112,7 @@ approximation that is “good enough.”

Procedure: cotan z
Procedure: cotan z: Return the cotangent of z.

diff --git a/manuals/chickadee/Bezier-Curves.html b/manuals/chickadee/Bezier-Curves.html index 6a49b59..ff04e6b 100644 --- a/manuals/chickadee/Bezier-Curves.html +++ b/manuals/chickadee/Bezier-Curves.html @@ -1,6 +1,6 @@ - @@ -110,39 +112,39 @@ mostly for visualizing and debugging curves that would be unseen in the final game. See See Lines and Shapes for more information.

Procedure: make-bezier-curve p0 p1 p2 p3
Procedure: make-bezier-curve p0 p1 p2 p3: Return a new Bezier curve object whose starting point is p0, ending point is p3, and control points are p1 and p2. All points are 2D vectors.

Procedure: bezier-curve? obj
Procedure: bezier-curve? obj: Return #t if obj is a Bezier curve.

Procedure: bezier-curve-p0 bezier
Procedure: bezier-curve-p0 bezier: Return the starting point of bezier.

Procedure: bezier-curve-p1 bezier
Procedure: bezier-curve-p1 bezier: Return the first control point of bezier.

Procedure: bezier-curve-p2 bezier
Procedure: bezier-curve-p2 bezier: Return the second control point of bezier.

Procedure: bezier-curve-p3 bezier
Procedure: bezier-curve-p3 bezier: Return the end point of bezier.

Procedure: bezier-path . control-points
Procedure: bezier-path . control-points: Return a list of connected bezier curves defined by control-points. The first curve is defined by the first 4 arguments and every additional curve thereafter requires 3 additional @@ -150,14 +152,14 @@ arguments.

Procedure: bezier-curve-point-at bezier t
Procedure: bezier-curve-point-at bezier t: Return the coordinates for bezier at t (a value in the range [0, 1] representing how far from the start of the curve to check) as a 2D vector.

Procedure: bezier-curve-point-at! dest bezier t
Procedure: bezier-curve-point-at! dest bezier t: Modify the 2D vector dest in-place to contain the coordinates for bezier at t.

diff --git a/manuals/chickadee/Blending.html b/manuals/chickadee/Blending.html new file mode 100644 index 0000000..6b3aa0d --- /dev/null +++ b/manuals/chickadee/Blending.html @@ -0,0 +1,137 @@ + + + + + + +Blending (The Chickadee Game Toolkit) + + + + + + + + + + + + + + + + + + + + + +

+ +

2.3.7 Blending

+ +

Rendering a scene often involves drawing layers of objects that +overlap each other. Blending determines how two overlapping pixels +are combined in the final image that is rendered to the screen. +Chickadee provides the following blend modes: +

replace +Use the latest color, ignoring all others. + +
alpha +Blend pixels according to the values of their alpha channels. This is +the most commonly used blend mode and thus is Chickadee’s default +mode. + +
add +Add all pixel color values together. The more colors blended +together, the more white the final color becomes. + +
subtract +Subtract all pixel color values. The more colors blended together, +the more black the final color becomes. + +
multiply + +
darken + +
lighten + +
screen + +

+ + + + + + diff --git a/manuals/chickadee/Buffers.html b/manuals/chickadee/Buffers.html new file mode 100644 index 0000000..00e3cfe --- /dev/null +++ b/manuals/chickadee/Buffers.html @@ -0,0 +1,473 @@ + + + + + + +Buffers (The Chickadee Game Toolkit) + + + + + + + + + + + + + + + + + + + + + +

+ +

2.3.11 Buffers

+ +

Alright, let’s brush aside all of those pretty high level abstractions +and discuss what is going on under the hood. The GPU exists as a +discrete piece of hardware separate from the CPU. In order to make it +draw things, we must ship lots of data out of our memory space and +into the GPU. The (chickadee render buffer) module provides an +API for manipulating GPU buffers. +

In OpenGL terminology, a chunk of data allocated on the GPU is a +“vertex buffer object” or VBO. For example, here is a bytevector +that could be transformed into a GPU buffer that packs together vertex +position and texture coordinates: +

(use-modules (chickadee render buffer) (srfi srfi-4))
+(define data
+  (f32vector -8.0 -8.0 ; 2D vertex
+             0.0 0.0   ; 2D texture coordinate
+             8.0 -8.0  ; 2D vertex
+             1.0 0.0   ; 2D texture coordinate
+             8.0 8.0   ; 2D vertex
+             1.0 1.0   ; 2D texture coordinate
+             -8.0 8.0  ; 2D vertex
+             0.0 1.0)) ; 2D texture coordinate
+

+ +

This data represents a textured 16x16 square centered on the +origin. To send this data to the GPU, the make-buffer procedure +is needed: +

(define buffer (make-buffer data #:stride 16))
+

+ +

The #:stride keyword argument indicates how many bytes make up +each element of the buffer. In this case, there are 4 floats per +element: 2 for the vertex, and 2 for the texture coordinate. A 32-bit +float is 4 bytes in length, so the buffer’s stride is 16. +

Within a VBO, one or more “attributes”, as OpenGL calls them, may be +present. Attributes are subregions within the buffer that have a +particular data type. In this case, there are two attributes packed +into the buffer. To provided a typed view into a buffer, the +make-buffer-view procedure is needed: +

(define vertices
+  (make-buffer-view #:buffer buffer
+                    #:type 'vec2
+                    #:component-type 'float
+                    #:length 4))
+(define texcoords
+  (make-buffer-view #:buffer buffer
+                    #:type 'vec2
+                    #:component-type 'float
+                    #:length 4
+                    #:offset 8))
+

+ +

To render a square, the GPU needs to draw two triangles, which means +we need 6 vertices in total. However, the above buffer only contains +data for 4 vertices. This is becase there are only 4 unique vertices +for a square, but 2 of them must be repeated for each triangle. To +work with deduplicated vertex data, an “index buffer” must be +created. +

(define index-buffer
+  (make-buffer (u32vector 0 3 2 0 2 1)
+               #:target 'index)
+(define indices
+  (make-buffer-view #:type 'scalar
+                    #:component-type 'unsigned-int
+                    #:buffer index-buffer))
+

+ +

Note the use of the #:target keyword argument. It is required +because the GPU treats index data in a special way and must be told +which data is index data. +

Now that the buffer views representing each attribute have been +created, all that’s left is to bind them all together in a “vertex +array object”, or VAO. Vertex arrays associate each buffer view +with an attribute index on the GPU. The indices that are chosen must +correspond with the indices that the shader (see Shaders) expects +for each attribute. +

(define vertex-array
+  (make-vertex-array #:indices indices
+                     #:attributes `((0 . ,vertices)
+                                    (1 . ,texcoords))))
+

+ +

With the vertex array created, the GPU is now fully aware of how to +interpret the data that it has been given in the original buffer. +Actually rendering this square is left as an exercise to the reader. +See the Shaders section and the gpu-apply procedure in +Rendering Engine for the remaining pieces of a successful draw +call. Additionally, consider reading the source code for sprites, +shapes, or particles to see GPU buffers in action. +

Without further ado, the API reference: +

Procedure: make-buffer data [#:name "anonymous"] [#:length] [#:offset 0] [#:stride 0] [#:target vertex] [#:usage static]

Upload data, a bytevector, to the GPU. By default, the entire +bytevector is uploaded. A subset of the data may be uploaded by +specifying the offset, the index of the first byte to be +uploaded, and length, the number of bytes to upload. +

If data is #f, allocate length bytes of fresh GPU +memory instead. +

target and usage are hints that tell the GPU how the +buffer is intended to be used. +

target may be: +

vertex +Vertex attribute data. + +
index +Index buffer data. + +

+ +

usage may be: +

static +The buffer data will not be modified after creation. + +
stream +The buffer data will be modified frequently. + +

+ +

name is simply an arbitrary string for debugging purposes that +is never sent to the GPU. +

+ +

Procedure: buffer? obj: Return #t if obj is a GPU buffer. +

+ +

Procedure: index-buffer? buffer: Return #t if buffer is an index buffer. +

+ +

Variable: null-buffer: Represents the absence of a buffer. +

+ +

Procedure: buffer-name buffer: Return the name of buffer. +

+ +

Procedure: buffer-length buffer: Return the length of buffer. +

+ +

Procedure: buffer-stride buffer: Return the amount of space, in bytes, between each element in +buffer. +

+ +

Procedure: buffer-target buffer: Return the the intended usage of buffer, either vertex or +index. +

+ +

Procedure: buffer-usage buffer: Return the intended usage of buffer, either static for +buffer data that will not change once sent to the GPU, or +stream for buffer data that will be frequently updated from the +client-side. +

+ +

Procedure: buffer-data buffer: Return a bytevector containing all the data within buffer. If +buffer has not been mapped (see with-mapped-buffer) then +this procedure will return #f. +

+ +

Syntax: with-mapped-buffer buffer body …

Evaluate body in the context of buffer having its data +synced from GPU memory to RAM. In this context, buffer-data +will return a bytevector of all the data stored in buffer. When +program execution exits this form, the data (including any +modifications) is synced back to the GPU. +

This form is useful for streaming buffers that need to update their +contents dynamically, such as a sprite batch. +

+ +

Procedure: make-buffer-view #:buffer #:type #:component-type #:length [#:offset 0] [#:divisor 1] [#:name "anonymous"]

Return a new buffer view for buffer starting at byte index +offset of length elements, where each element is of +type and composed of component-type values. +

Valid values for type are: +

scalar +single number + +
vec2 +2D vector + +
vec3 +3D vector + +
vec4 +4D vector + +
mat2 +2x2 matrix + +
mat3 +3x3 matrix + +
mat4 +4x4 matrix +

+ +

Valid values for component-type are: +

byte +
unsigned-byte +
short +
unsigned-short +
int +
unsigned-int +
float +
double + +

+ +

divisor is only needed for instanced rendering applications (see +gpu-apply/instanced in Rendering Engine) and represents +how many instances each vertex element applies to. A divisor of 0 +means that a single element is used for every instance and is used for +the data being instanced. A divisor of 1 means that each element is +used for 1 instance. A divisor of 2 means that each element is used +for 2 instances, and so on. +

+ +

Procedure: buffer-view? obj: Return #t if obj is a buffer view. +

+ +

Procedure: buffer-view->buffer buffer-view: Return the buffer that buffer-view is using. +

+ +

Procedure: buffer-view-name buffer-view: Return the name of buffer-view. +

+ +

Procedure: buffer-view-offset buffer-view: Return the byte offset of buffer-view. +

+ +

Procedure: buffer-view-type buffer-view: Return the data type of buffer-view. +

+ +

Procedure: buffer-view-component-type buffer-view: Return the component data type of buffer-view +

+ +

Procedure: buffer-view-divisor buffer-view: Return the instance divisor for buffer-view. +

+ +

Syntax: with-mapped-buffer-view buffer-view body …: +
Evaluate body in the context of buffer-view having its +data synced from GPU memory to RAM. See with-mapped-buffer for +more information. +

+ +

Procedure: make-vertex-array #:indices #:attributes [#:mode triangles]

Return a new vertex array using the index data within the buffer view +indices and the vertex attribute data within attributes. +

attributes is an alist mapping shader attribute indices to typed +buffers containing vertex data: +

`((1 . ,buffer-view-a)
+  (2 . ,buffer-view-b)
+  …)
+

+ +

By default, the vertex array is interpreted as containing a series of +triangles. If another primtive type is desired, the mode +keyword argument may be overridden. The following values are +supported: +

points +
lines +
line-loop +
line-strip +
triangles +
triangle-strip +
triangle-fan +

+ +

Variable: null-vertex-array: Represents the absence of a vertex array. +

+ +

Procedure: vertex-array? obj: Return #t if obj is a vertex array. +

+ +

Procedure: vertex-array-indices vertex-array: Return the buffer view containing index data for vertex-array. +

+ +

Procedure: vertex-array-attributes vertex-array: Return the attribute index -> buffer view mapping of vertex attribute +data for vertex-array. +

+ +

Procedure: vertex-array-mode vertex-array: Return the primitive rendering mode for vertex-array. +

+ +

+ + + + + + diff --git a/manuals/chickadee/Channels.html b/manuals/chickadee/Channels.html index f313c4f..ece7ce5 100644 --- a/manuals/chickadee/Channels.html +++ b/manuals/chickadee/Channels.html @@ -1,6 +1,6 @@ - @@ -123,22 +125,37 @@ someone on the other end of the line to complete the transaction.

Procedure: channel? obj
Procedure: channel? obj: Return #t if obj is a channel.

Procedure: channel-get channel
Procedure: channel-get channel: Retrieve a value from channel. The current script suspends until a value is available.

Procedure: channel-put channel data
Procedure: channel-put channel data: Send data to channel. The current script suspends until another script is available to retrieve the value.

A low-level API also exists for using channels outside of a script via +callback procedures: +

Procedure: channel-get! channel proc: Asynchronously retrieve a value from channel and call proc +with that value. +

+ +

Procedure: channel-put! channel data [thunk]: Asynchronously send data to channel and call thunk +after it has been received. +

+ diff --git a/manuals/chickadee/Copying-This-Manual.html b/manuals/chickadee/Copying-This-Manual.html index f9a7c77..d91e4bd 100644 --- a/manuals/chickadee/Copying-This-Manual.html +++ b/manuals/chickadee/Copying-This-Manual.html @@ -1,6 +1,6 @@ - diff --git a/manuals/chickadee/Easings.html b/manuals/chickadee/Easings.html index 55f385c..14207d0 100644 --- a/manuals/chickadee/Easings.html +++ b/manuals/chickadee/Easings.html @@ -1,6 +1,6 @@ - @@ -96,72 +98,81 @@ Next: Bezier

2.2.7 Easings

Easing functions are essential for animation. Each easing function +provides a different path to go from an initial value to a final +value. These functions make an excellent companion to the +tween procedure (see Tweening). Experiment with them to +figure out which function makes an animation look the best. +

Pro tip: smoothstep provides nice results most of the time and +creates smoother animation than using linear. +

Procedure: linear t
Procedure: linear t

Procedure: smoothstep t
Procedure: smoothstep t

Procedure: ease-in-quad t
Procedure: ease-in-quad t

Procedure: ease-out-quad t
Procedure: ease-out-quad t

Procedure: ease-in-out-quad t
Procedure: ease-in-out-quad t

Procedure: ease-in-cubic t
Procedure: ease-in-cubic t

Procedure: ease-out-cubic t
Procedure: ease-out-cubic t

Procedure: ease-in-out-cubic t
Procedure: ease-in-out-cubic t

Procedure: ease-in-quart t
Procedure: ease-in-quart t

Procedure: ease-out-quart t
Procedure: ease-out-quart t

Procedure: ease-in-out-quart t
Procedure: ease-in-out-quart t

Procedure: ease-in-quint t
Procedure: ease-in-quint t

Procedure: ease-out-quint t
Procedure: ease-out-quint t

Procedure: ease-in-out-quint t
Procedure: ease-in-out-quint t

Procedure: ease-in-sine t
Procedure: ease-in-sine t

Procedure: ease-out-sine t
Procedure: ease-out-sine t

Procedure: ease-in-out-sine t
Procedure: ease-in-out-sine t

diff --git a/manuals/chickadee/Fonts.html b/manuals/chickadee/Fonts.html index a4ed5c6..d65d67c 100644 --- a/manuals/chickadee/Fonts.html +++ b/manuals/chickadee/Fonts.html @@ -1,6 +1,6 @@ - @@ -30,7 +32,7 @@ http://www.texinfo.org/ (GNU Texinfo). - + + + + + + + + + +

+ +

2.3.6 Particles

+ +

Effects like smoke, fire, sparks, etc. are often achieved by animating +lots of little, short-lived sprites known as “particles”. In fact, +all of these effects, and more, can be accomplished by turning a few +configuration knobs in a “particle system”. A particle system takes +care of managing the many miniscule moving morsels so the developer +can quickly produce an effect and move on with their life. The +(chickadee render particles) module provides an API for +manipulating particle systems. +

Below is an example of a very simple particle system that utilizes +nearly all of the default configuration settings: +

(use-modules (chickadee render particles))
+(define texture (load-image "particle.png"))
+(define particles (make-particles 2000 #:texture texture))
+

+ +

In order to put particles into a particle system, a particle +“emitter” is needed. Emitters know where to spawn new particles, +how many of them to spawn, and for how long they should do it. +

Below is an example of an emitter that spawns 16 particles per frame +at the coordinates (320, 240): +

(use-modules (chickadee math vector))
+(define emitter (make-particle-emitter (vec2 320.0 240.0) 16))
+(add-particle-emitter particles emitter)
+

+ +

To see all of the tweakable knobs and switches, read on! +

Procedure: make-particles capacity [#:blend-mode alpha] [#:color white] [#:end-color transparent] [#:texture] [#:animation-rows 1] [#:animation-columns 1] [#:width] [#:height] [#:speed-range (vec2 0.1 1.0)] [#:acceleration-range (vec2 0.0 0.1)] [#:direction-range (vec2 0 (* 2 pi))] [#:lifetime 30] [#:sort]

Return a new particle system that may contain up to capacity +particles. Achieving the desired particle effect involves tweaking +the following keyword arguments as needed: +

- blend-mode: Pixel blending mode. alpha by default. +(see Blending for more about blend modes). +

- start-color: The tint color of the particle at the beginning of its +life. White by default. +

- end-color: The tint color of the particle at the end of of its +life. Completely transparent by default for a fade-out effect. The +color in the middle of a particle’s life will be an interpolation of +start-color and end-color. +

- texture: The texture applied to the particles. The texture +may be subdivided into many animation frames. +

- animation-rows: How many animation frame rows there are in the +texture. Default is 1. +

- animation-columns: How many animation frame columns there are +in the texture. Default is 1. +

- width: The width of each particle. By default, the width of +an animation frame (in pixels) is used. +

- height: The height of each particle. By default, the height +of an animation frame (in pixels) is used. +

- speed-range: A 2D vector containing the min and max particle +speed. Each particle will have a speed chosen at random from this +range. By default, speed ranges from 0.1 to 1.0. +

- acceleration-range: A 2D vector containing the min and max +particle acceleration. Each particle will have an acceleration chosen +at random from this range. By default, acceleration ranges from 0.0 +to 0.1. +

- direction-range: A 2D vector containing the min and max +particle direction as an angle in radians. Each particle will have a +direction chosen at random from this range. By default, the range +covers all possible angles. +

- lifetime: How long each particle lives, measured in +updates. 30 by default. +

- sort: youngest if youngest particle should be drawn +last or oldest for the reverse. By default, no sorting is +applied at all. +

+ +

Procedure: particles? obj: Return #t if obj is a particle system. +

+ +

Procedure: update-particles particles: Advance the simulation of particles. +

+ +

Procedure: draw-particles particles: Render particles. +

+ +

Procedure: draw-particles* particles matrix: Render particles with matrix applied. +

+ +

Procedure: make-particle-emitter spawn-area rate [duration]: +
Return a new particle emitter that spawns rate particles per +frame within spawn-area (a rectangle or 2D vector) for +duration frames. If duration is not specified, the +emitter will spawn particles indefinitely. +

+ +

Procedure: particle-emitter? obj: Return #t if obj is a particle emitter. +

+ +

Procedure: particle-emitter-spawn-area emitter: Return the spawn area for emitter. +

+ +

Procedure: particle-emitter-rate emitter: Return the number of particles that emitter will spawn per +frame. +

+ +

Procedure: particle-emitter-life emitter: Return the number of frames remaining in emitter’s lifespan. +

+ +

Procedure: particle-emitter-done? emitter: Return #t if emitter has finished spawning particlces. +

+ +

Procedure: add-particle-emitter particles emitter: Add emitter to particles. +

+ +

Procedure: remove-particle-emitter particles emitter: Remove emitter to particles +

+ +

+ + + + + + diff --git a/manuals/chickadee/Path-Finding.html b/manuals/chickadee/Path-Finding.html index 63819aa..255eba7 100644 --- a/manuals/chickadee/Path-Finding.html +++ b/manuals/chickadee/Path-Finding.html @@ -1,6 +1,6 @@ - @@ -152,12 +154,12 @@ for optimal path finding!

Procedure: path-finder? obj
Procedure: path-finder? obj: Return #t if obj is a path finder.

Procedure: a* path-finder start goal neighbors cost distance

Procedure: a* path-finder start goal neighbors cost distance

Return a list of nodes forming a path from start to goal using path-finder to hold state. neighbors is a procedure diff --git a/manuals/chickadee/Quaternions.html b/manuals/chickadee/Quaternions.html index de4c8e4..ebda6e9 100644 --- a/manuals/chickadee/Quaternions.html +++ b/manuals/chickadee/Quaternions.html @@ -1,6 +1,6 @@ - @@ -104,33 +106,33 @@ smooth transition from one rotation to another, whereas interpolating two matrices would yield garbage.

Procedure: quaternion x y z w
Procedure: quaternion x y z w: Return a new quaternion with values x, y, z, and w.

Procedure: quaternion? obj
Procedure: quaternion? obj: Return #t if obj is a quaternion.

Procedure: quaternion-w q
Procedure: quaternion-w q: Return the W component of the quaternion q.

Procedure: quaternion-x q
Procedure: quaternion-x q: Return the X component of the quaternion q.

Procedure: quaternion-y q
Procedure: quaternion-y q: Return the Y component of the quaternion q.

Procedure: quaternion-z q
Procedure: quaternion-z q: Return the Z component of the quaternion q.

diff --git a/manuals/chickadee/Rectangles.html b/manuals/chickadee/Rectangles.html index edaf4e6..ecfbde0 100644 --- a/manuals/chickadee/Rectangles.html +++ b/manuals/chickadee/Rectangles.html @@ -1,6 +1,6 @@ - @@ -108,220 +110,221 @@ functions that do in-place modification of rectangles for use in performance critical code paths.

Procedure: rect x y width height
Procedure: make-rect x y width height: Create a new rectangle that is width by height in size and whose bottom-left corner is located at (x, y).

Procedure: rect? obj
Procedure: rect? obj: Return #t if obj is a rectangle.

Procedure: rect-within? rect1 rect2
Procedure: rect-within? rect1 rect2: Return #t if rect2 is completely within rect1.

Procedure: rect-intersects? rect1 rect2
Procedure: rect-intersects? rect1 rect2: Return #t if rect2 overlaps rect1.

Procedure: rect-contains? rect x y
Procedure: rect-contains? rect x y: Return #t if the coordinates (x, y) are within rect.

Procedure: rect-contains-vec2? rect v
Procedure: rect-contains-vec2? rect v: Return #t if the 2D vector v is within the bounds of rect.

Procedure: rect-x rect
Procedure: rect-x rect: Return the X coordinate of the lower-left corner of rect.

Procedure: rect-y rect
Procedure: rect-y rect: Return the Y coordinate of the lower-left corner of rect.

Procedure: rect-left rect
Procedure: rect-left rect: Return the left-most X coordinate of rect.

Procedure: rect-right rect
Procedure: rect-right rect: Return the right-most X coordinate of rect.

Procedure: rect-bottom rect
Procedure: rect-bottom rect: Return the bottom-most Y coordinate of rect.

Procedure: rect-top rect
Procedure: rect-top rect: Return the top-most Y coordinate of rect.

Procedure: rect-center-x rect
Procedure: rect-center-x rect: Return the X coordinate of the center of rect.

Procedure: rect-center-y rect
Procedure: rect-center-y rect: Return the Y coordinate of the center of rect.

Procedure: rect-width rect
Procedure: rect-width rect: Return the width of rect.

Procedure: rect-height rect
Procedure: rect-height rect: Return the height of rect.

Procedure: rect-area rect
Procedure: rect-area rect: Return the surface area covered by rect.

Procedure: rect-clamp-x rect x
Procedure: rect-clamp-x rect x: Restrict x to the portion of the X axis covered by rect.

Procedure: rect-clamp-y rect y
Procedure: rect-clamp-y rect y: Restrict y to the portion of the Y axis covered by rect.

Procedure: rect-clamp rect1 rect2
Procedure: rect-clamp rect1 rect2: Return a new rect that adjusts the location of rect1 so that it is completely within rect2. An exception is thrown in the case that rect1 cannot fit completely within rect2.

Procedure: rect-move rect x y
Procedure: rect-move rect x y: Return a new rectangle based on rect but moved to the coordinates (x, y).

Procedure: rect-move-vec2 rect v
Procedure: rect-move-vec2 rect v: Return a new rectangle based on rect but moved to the coordinates in the 2D vector v.

Procedure: rect-move-by rect x y
Procedure: rect-move-by rect x y: Return a new rectangle based on rect but moved by (x, y) units relative to its current location.

Procedure: rect-move-by-vec2 rect v
Procedure: rect-move-by-vec2 rect v: Return a new rectangle based on rect but moved by the 2D vector v relative to its current location.

Procedure: rect-inflate rect width height
Procedure: rect-inflate rect width height: Return a new rectangle based on rect, but expanded by width units on the X axis and height units on the Y axis, while keeping the rectangle centered on the same point.

Procedure: rect-union rect1 rect2
Procedure: rect-union rect1 rect2: Return a new rectangle that completely covers the area of rect1 and rect2.

Procedure: rect-clip rect1 rect2
Procedure: rect-clip rect1 rect2: Return a new rectangle that is the overlapping region of rect1 and rect2. If the two rectangles do not overlap, a rectangle of 0 width and 0 height is returned.

Procedure: set-rect-x! rect x
Procedure: set-rect-x! rect x: Set the left X coordinate of rect to x.

Procedure: set-rect-y! rect y
Procedure: set-rect-y! rect y: Set the bottom Y coordinate of rect to y.

Procedure: set-rect-width! rect width
Procedure: set-rect-width! rect width: Set the width of rect to width.

Procedure: set-rect-height! rect height
Procedure: set-rect-height! rect height: Set the height of rect to height.

Procedure: rect-move! rect x y
Procedure: rect-move! rect x y: Move rect to (x, y) in-place.

Procedure: rect-move-vec2! rect v
Procedure: rect-move-vec2! rect v: Move rect to the 2D vector v in-place.

Procedure: rect-move-by! rect x y
Procedure: rect-move-by! rect x y: Move rect by (x, y) in-place.

Procedure: rect-move-by-vec2! rect v
Procedure: rect-move-by-vec2! rect v: Move rect by the 2D vector v in-place.

Procedure: rect-inflate! rect width height
Procedure: rect-inflate! rect width height: Expand rect by width and height in-place.

Procedure: rect-union! rect1 rect2
Procedure: rect-union! rect1 rect2: Modify rect1 in-place to completely cover the area of both rect1 and rect2.

Procedure: rect-clip! rect1 rect2
Procedure: rect-clip! rect1 rect2: Modify rect1 in-place to be the overlapping region of rect1 and rect2.

Procedure: rect-clamp! rect1 rect2
Procedure: rect-clamp! rect1 rect2: Adjust the location of rect1 in-place so that its bounds are completely within rect2. An exception is thrown in the case that rect1 cannot fit completely within rect2.

Procedure: vec2-clamp-to-rect! v rect
Procedure: vec2-clamp-to-rect! v rect: Restrict the coordinates of the 2D vector v so that they are within the bounds of rect. v is modified in-place.

diff --git a/manuals/chickadee/Rendering-Engine.html b/manuals/chickadee/Rendering-Engine.html index fa9f021..daef0ce 100644 --- a/manuals/chickadee/Rendering-Engine.html +++ b/manuals/chickadee/Rendering-Engine.html @@ -1,6 +1,6 @@ - @@ -30,8 +32,8 @@ http://www.texinfo.org/ (GNU Texinfo). - - + +