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Simon Schneegans
2021-12-31 20:34:50 +01:00
parent 0ee171aae0
commit 03db97fdda
+16 -6
View File
@@ -20,7 +20,9 @@ const Me = imports.misc.extensionUtils.getCurrentExtension();
const shaderSnippets = Me.imports.src.extension.shaderSnippets;
//////////////////////////////////////////////////////////////////////////////////////////
// The TVEffectShader ... //
// The TVEffectShader hides the actor by making it first transparent from top and //
// bottom towards the middle and then hiding the resulting line from left and right //
// towards the center. //
//////////////////////////////////////////////////////////////////////////////////////////
var TVEffectShader = GObject.registerClass(
@@ -33,28 +35,36 @@ var TVEffectShader = GObject.registerClass(
// Inject some common shader snippets.
${shaderSnippets.standardUniforms()}
const float BLUR_WIDTH = 0.01;
const float TB_TIME = 0.7;
const float LR_TIME = 0.4;
const float LR_DELAY = 0.6;
const float FF_TIME = 0.2;
const float BLUR_WIDTH = 0.01; // Width of the gradients.
const float TB_TIME = 0.7; // Relative time for the top/bottom animation.
const float LR_TIME = 0.4; // Relative time for the left/right animation.
const float LR_DELAY = 0.6; // Delay after which the left/right animation starts.
const float FF_TIME = 0.2; // Relative time for the final fade to transparency.
void main() {
// All of these are in [0..1] during the different stages of the animation.
// tb refers to the top-bottom animation.
// lr refers to the left-right animation.
// ff refers to the final fade animation.
float tbProgress = smoothstep(0, 1, clamp(uProgress/TB_TIME, 0, 1));
float lrProgress = smoothstep(0, 1, clamp((uProgress - LR_DELAY)/LR_TIME, 0, 1));
float ffProgress = smoothstep(0, 1, clamp((uProgress - 1.0 + FF_TIME)/FF_TIME, 0, 1));
// This is a top-center-bottom gradient in [0..1..0]
float tb = cogl_tex_coord_in[0].t * 2;
tb = tb < 1 ? tb : 2 - tb;
// This is a left-center-right gradient in [0..1..0]
float lr = cogl_tex_coord_in[0].s * 2;
lr = lr < 1 ? lr : 2 - lr;
// Combine the progress values with the gradients to create the alpha masks.
float tbMask = 1 - smoothstep(0, 1, clamp((tbProgress - tb) / BLUR_WIDTH, 0, 1));
float lrMask = 1 - smoothstep(0, 1, clamp((lrProgress - lr) / BLUR_WIDTH, 0, 1));
float ffMask = 1 - smoothstep(0, 1, ffProgress);
// Assemble the final alpha value.
float mask = tbMask * lrMask * ffMask;
vec4 windowColor = texture2D(uTexture, cogl_tex_coord_in[0].st);