Mouse wheel and middle mouse button to control camera

Redefined classes

redef class EulerCamera

gamnit :: camera_control_linux $ EulerCamera

Simple camera with perspective oriented with Euler angles (pitch, yaw, roll)

All class definitions

redef class EulerCamera

gamnit :: camera_control_linux $ EulerCamera

Simple camera with perspective oriented with Euler angles (pitch, yaw, roll)
package_diagram gamnit::camera_control_linux camera_control_linux linux linux gamnit::camera_control_linux->linux gamnit::camera_control camera_control gamnit::camera_control_linux->gamnit::camera_control gamnit::gamnit_linux gamnit_linux gamnit::camera_control_linux->gamnit::gamnit_linux app app linux->app sdl2 sdl2 linux->sdl2 xdg_basedir xdg_basedir linux->xdg_basedir sqlite3 sqlite3 linux->sqlite3 json json linux->json curl curl linux->curl gtk gtk linux->gtk gamnit gamnit gamnit::camera_control->gamnit gamnit::cameras cameras gamnit::camera_control->gamnit::cameras gamnit::gamnit_linux->gamnit gamnit::display_linux display_linux gamnit::gamnit_linux->gamnit::display_linux ...>app ...sdl2 ... ...sdl2->sdl2 ...xdg_basedir ... ...xdg_basedir->xdg_basedir ...sqlite3 ... ...sqlite3->sqlite3 ...json ... ...json->json ...curl ... ...curl->curl ...gtk ... ...gtk->gtk ...gamnit ... ...gamnit->gamnit ...gamnit::cameras ... ...gamnit::cameras->gamnit::cameras ...gamnit::display_linux ... ...gamnit::display_linux->gamnit::display_linux a_star-m a_star-m a_star-m->gamnit::camera_control_linux


module abstract_collection

core :: abstract_collection

Abstract collection classes and services.
module abstract_text

core :: abstract_text

Abstract class for manipulation of sequences of characters
module angles

geometry :: angles

Angle related service using Float to represent an angle in radians
module app

app :: app

app.nit is a framework to create cross-platform applications
module app_base

app :: app_base

Base of the app.nit framework, defines App
module array

core :: array

This module introduces the standard array structure.
module assets

app :: assets

Portable services to load resources from the assets folder
module aware

android :: aware

Android compatibility module
module bitset

core :: bitset

Services to handle BitSet
module boxes

geometry :: boxes

Provides interfaces and classes to represent basic geometry needs.
module bytes

core :: bytes

Services for byte streams and arrays
module c

c :: c

Structures and services for compatibility with the C language
module caching

serialization :: caching

Services for caching serialization engines
module cameras

gamnit :: cameras

Camera services producing Model-View-Projection matrices
module circular_array

core :: circular_array

Efficient data structure to access both end of the sequence.
module codec_base

core :: codec_base

Base for codecs to use with streams
module codecs

core :: codecs

Group module for all codec-related manipulations
module collection

core :: collection

This module define several collection classes.
module core

core :: core

Standard classes and methods used by default by Nit programs and libraries.
module display

gamnit :: display

Abstract display services
module display_linux

gamnit :: display_linux

Gamnit display implementation for GNU/Linux using egl, sdl and x11
module egl

gamnit :: egl

Use of EGL to implement Gamnit on GNU/Linux and Android
module egl

egl :: egl

Interface between rendering APIs (OpenGL, OpenGL ES, etc.) and the native windowing system.
module engine_tools

serialization :: engine_tools

Advanced services for serialization engines
module environ

core :: environ

Access to the environment variables of the process
module error

core :: error

Standard error-management infrastructure.
module events

sdl2 :: events

SDL 2 events and related services
module exec

core :: exec

Invocation and management of operating system sub-processes.
module file

core :: file

File manipulations (create, read, write, etc.)
module fixed_ints

core :: fixed_ints

Basic integers of fixed-precision
module fixed_ints_text

core :: fixed_ints_text

Text services to complement fixed_ints
module flat

core :: flat

All the array-based text representations
module gamnit

gamnit :: gamnit

Game and multimedia framework for Nit
module gc

core :: gc

Access to the Nit internal garbage collection mechanism
module geometry

geometry :: geometry

Provides interfaces and classes to represent basic geometry needs.
module glesv2

glesv2 :: glesv2

OpenGL graphics rendering library for embedded systems, version 2.0
module hash_collection

core :: hash_collection

Introduce HashMap and HashSet.
module image

sdl2 :: image

Services of the SDL_image 2.0 library
module input

mnit :: input

Defines abstract classes for user and general inputs to the application.
module inspect

serialization :: inspect

Refine Serializable::inspect to show more useful information
module iso8859_1

core :: iso8859_1

Codec for ISO8859-1 I/O
module kernel

core :: kernel

Most basic classes and methods.
module list

core :: list

This module handle double linked lists
module math

core :: math

Mathematical operations
module matrix

matrix :: matrix

Services for matrices of Float values
module meta

meta :: meta

Simple user-defined meta-level to manipulate types of instances as object.
module mixer

sdl2 :: mixer

SDL2 mixer with sample/sounds and music
module more_collections

more_collections :: more_collections

Highly specific, but useful, collections-related classes.
module native

core :: native

Native structures for text and bytes
module numeric

core :: numeric

Advanced services for Numeric types
module points_and_lines

geometry :: points_and_lines

Interfaces and classes to represent basic geometry needs.
module poset

poset :: poset

Pre order sets and partial order set (ie hierarchies)
module programs

gamnit :: programs

Services for graphical programs with shaders, attributes and uniforms
module projection

matrix :: projection

Services on Matrix to transform and project 3D coordinates
module protocol

core :: protocol

module queue

core :: queue

Queuing data structures and wrappers
module range

core :: range

Module for range of discrete objects.
module re

core :: re

Regular expression support for all services based on Pattern
module ropes

core :: ropes

Tree-based representation of a String.
module sdl2

sdl2 :: sdl2

Simple DirectMedia Layer (SDL) 2.0 services for easy window creation and 2D drawing
module sdl2_base

sdl2 :: sdl2_base

Basic SDL 2 features
module serialization

serialization :: serialization

General serialization services
module serialization_core

serialization :: serialization_core

Abstract services to serialize Nit objects to different formats
module sorter

core :: sorter

This module contains classes used to compare things and sorts arrays.
module stream

core :: stream

Input and output streams of characters
module syswm

sdl2 :: syswm

Window manager related SDL 2 services
module text

core :: text

All the classes and methods related to the manipulation of text entities
module textures

gamnit :: textures

Load textures, create subtextures and manage their life-cycle
module time

core :: time

Management of time and dates
module union_find

core :: union_find

union–find algorithm using an efficient disjoint-set data structure
module utf8

core :: utf8

Codec for UTF-8 I/O


module camera_control

gamnit :: camera_control

Simple camera control for user, as the method accept_scroll_and_zoom
module gamnit_linux

gamnit :: gamnit_linux

Support services for Gamnit on GNU/Linux
module linux

linux :: linux

Implementation of app.nit for the Linux platform


module a_star-m


# Mouse wheel and middle mouse button to control camera
module camera_control_linux

import linux
import camera_control

redef class EulerCamera

	# Zoom factor, default at 1.2, higher means more reactive zoom effect
	var camera_zoom_mod = 1.2 is writable

	# Scroll trigger button mask from SDL2 (1: left, 2: middle, 4: right)
	# Set to 0 to deactivate the scrolling feature.
	var camera_pan_mask = 2 is writable

	redef fun accept_scroll_and_zoom(event)
		# Zoom
		if event isa GamnitMouseWheelEvent then
			var dy = event.y
			var mod = camera_zoom_mod
			if dy > 0.0 then
				# Zoom in when moving the wheel up
				mod = 1.0/mod
			else dy = -dy

			position.z *= dy * mod
			return true

		# Scroll
		var but_mask = camera_pan_mask
		if but_mask != 0 and event isa GamnitPointerEvent then
			var native = event.native
			if native isa SDLMouseMotionEvent and native.state & but_mask == but_mask then
				var dx = native.xrel.to_f
				var dy = native.yrel.to_f

				var world_height = field_of_view_y.sin * position.z
				var mod = null).height.to_f / world_height
				position.x -= dx / mod
				position.y += dy / mod # Y is inverted between the input and output
				return true

		return false