63 lines
1.7 KiB
Python
63 lines
1.7 KiB
Python
'''
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This example demonstrates creating and using an AdvancedEffectBase. In
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this case, we use it to efficiently pass the touch coordinates into the shader.
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'''
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from kivy.base import runTouchApp
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from kivy.properties import ListProperty
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from kivy.lang import Builder
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from kivy.uix.effectwidget import EffectWidget, AdvancedEffectBase
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effect_string = '''
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uniform vec2 touch;
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vec4 effect(vec4 color, sampler2D texture, vec2 tex_coords, vec2 coords)
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{
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vec2 distance = 0.025*(coords - touch);
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float dist_mag = (distance.x*distance.x + distance.y*distance.y);
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vec3 multiplier = vec3(abs(sin(dist_mag - time)));
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return vec4(multiplier * color.xyz, 1.0);
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}
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'''
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class TouchEffect(AdvancedEffectBase):
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touch = ListProperty([0.0, 0.0])
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def __init__(self, *args, **kwargs):
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super(TouchEffect, self).__init__(*args, **kwargs)
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self.glsl = effect_string
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self.uniforms = {'touch': [0.0, 0.0]}
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def on_touch(self, *args, **kwargs):
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self.uniforms['touch'] = [float(i) for i in self.touch]
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class TouchWidget(EffectWidget):
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def __init__(self, *args, **kwargs):
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super(TouchWidget, self).__init__(*args, **kwargs)
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self.effect = TouchEffect()
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self.effects = [self.effect]
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def on_touch_down(self, touch):
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super(TouchWidget, self).on_touch_down(touch)
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self.on_touch_move(touch)
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def on_touch_move(self, touch):
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self.effect.touch = touch.pos
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root = Builder.load_string('''
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TouchWidget:
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Button:
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text: 'Some text!'
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Image:
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source: 'data/logo/kivy-icon-512.png'
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fit_mode: "fill"
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''')
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runTouchApp(root)
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