Functions

From The Powder Toy
Revision as of 21:31, 8 August 2017 by Mrprocom (talk | contribs) (Fix typo: overrite => override)
Jump to: navigation, search

When you are modding TPT++ and come to writing the update routine, there are a few functions you will need to use. A reference of those is shown below.

sim->create_part(int p, int x, int y, int t);
What it does: Creates a particle at a given coordinate.
int p - How the particle is created. -1 means from the code (will only create a particle if the space is empty). This is the normal way to create a particle, -2 is from the brush (don't use this), -3 means it will ignore any particles in the space and draw it anyway, and any positive number will override the particle at that index with this newly created particle.
int x - Particle's x coordinate
int y - Particle's y coordinate
int t - Particle's type. Use a pre-defined value, such as PT_INST.
sim->kill_part(int i) - Deletes particle with index i
What it does: Deletes a particle without the given x and y, using its index instead.
int i - The particle's index. Passed into the function as 'i'.
sim->delete_part(int x, int y, int flags);
What it does: Deletes a particle at location (x, y)
int x - Particle's x coordinate
int y - Particle's y coordinate
int flags - Un-useful value, leave it as 0
sim->part_change_type(int i, int x, int y, int t);
What it does: Changes type of particle i. Do not manually set parts[].type, use this function instead.
int i - The particle's index.
int x - Particle's x coordinate. Pass in parts[i].x here.
int y - Particle's y coordinate. Pass in parts[i].y here.
int t - Particle's type. Use a pre-defined value, such as PT_INST.
sim->clear_area(int x, int y, int w, int h);
What it does: Clears a rectangle with specified height and width.
int x - Top left corner's x coordinate (from left towards the right)
int y - Top left corner's y coordinate (from top downwards!)
int w - The width of the rectangle
int h - The height of the rectangle
sim->CreateBox(int x1, int y1, int x2, int y2, int t, int flags)
What it does: Utility function, creates a rectangle of a given particle.
For some reason, this uses a different way to specify a rectangle than the deleting equivalent.
int x1 - Top left corner's x coordinate
int y1 - Top right corner's y coordinate
int x2 - Bottom left corner's x coordinate (note: not the box's width!)
int y2 - Bottom left corner's y coordinate (see note above)
int t - Particle's type. Use a pre-defined value, such as PT_INST.
int flags - Un-useful value, leave it as 0
sim->CreateLine(int x1, int y1, int x2, int y2, int c)
What it does: Draws a single pixel line of a specified element from two points.
int x1 - Line start's x coordinate.
int y1 - Line start's y coordinate.
int x2 - Line end's x coordinate.
int y2 - Line end's y coordinate.
int c - Particle's type. Use a pre-defined value, such as PT_INST.
sim->FloodParts(int x, int y, int t, int cm, int bm, int flags);
What it does: Starts a flood-fill from a point. (like ctrl+shift+clicking in TPT)
int x - Particle's x coordinate
int y - Particle's y coordinate
int t - Particle's type. Use a pre-defined value, such as PT_INST.
int cm - used by recursion in the code, leave it as -1
int bm - used by recursion in the code, leave it as -1
int flags - Un-useful value, leave it as 0
sim->flood_prop(int x, int y, size_t propoffset, PropertyValue propvalue, StructProperty::PropertyType proptype);
What it does: Sets a property via flood-fill. (Like PROP)
int x - Particle's x coordinate
int y - Particle's y coordinate
size_t propoffset - This is a value returned by the function offsetof(Particle, <property>).
Replace <property> with what you want, for example tmp or ctype.
PropertyValue propvalue - A c++ union, which holds the property you want to set. You may declare PropertyValue value;, then do value.Integer = 2; in order to use this. The other two properties you can set are .Float (if setting temperature or veloticy) and .UInteger (if setting decoration color)
StructProperty::PropertyType proptype - What kind of type the value you provided is.
For example, if you had a temperature number (as an integer), then you could use StructProperty::Integer.
The types are: StructProperty::Integer, StructProperty::Float and StructProperty::Uinteger
sim->parts_avg(int i, int ni, int t);
What it does: Checks if an element of type t is inbetween the two particles specified as indexes.
int i - The (first) particle's index. Passed into the function as 'i'.
int ni - The other particle's index.
int t - Particle's type. Use a pre-defined value, such as PT_INST.
It will actually only check the location directly in the middle
Returns: 0 if there isn't an element of type t in between the two, 1 if there is.