added Type Jam puzzle app for review (#1554)

* added Type Jam puzzle app for review

* pr round 2 prep

* updated ci scripts for varfont_shader_puzzle

* resolved unused and minor variable naming issues

* rotator tiles row and col are final vars now

* removed unused import and print from production

* made constructors const where needed

* pages_flow export refactored to directly come from that file

* removed old api commented out section from FragmentShaded

* updated pubspec yaml to correct project name

* dart min version updated; removed unnecessary commented out dependencies from pubspec.yaml

* updated pubspec.yaml min flutter version to ensure FragmentShader support

* added/edited comments for explanation, esp on var fonts; removed obsolete comments

* trailing newline added to pubspec.yaml eof

experimental/varfont_shader_puzzle/shaders/bw_split.frag

@@ -0,0 +1,40 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize;
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  float offset = 50;
+  
+  float opacSum = 0.0;
+  vec4 thisCol = texture(uTexture, texCoord.xy);
+
+  float x = texCoord.x + (offset / uSize.x * pow(sin(piTime), 4)) * uDampener;
+  if (x >= 0.0 && x <= 1.0) {
+    opacSum += 0.3 * texture(uTexture, vec2(x, texCoord.y)).a;  
+  }
+  
+  x = texCoord.x - (offset / uSize.x * pow(sin(piTime + PI), 2)) * uDampener;
+  if (x >= 0.0 && x <= 1.0) {
+    opacSum += 0.3 * texture(uTexture, vec2(x, texCoord.y)).a;
+  }
+
+  float y = texCoord.y + (offset / uSize.y * pow(sin(piTime + PI * 0.66), 4)) * uDampener;
+  if (y >= 0.0 && y <= 1.0) {
+    opacSum += 0.3 * texture(uTexture, vec2(texCoord.x, y)).a;
+  }
+
+  fragColor = vec4(0.0, 0.0, 0.0, clamp(opacSum, 0.0, 1.0));    
+
+}

experimental/varfont_shader_puzzle/shaders/color_split.frag

@@ -0,0 +1,30 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize;
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  float offset = 15;
+
+  vec4 thisCol = texture(uTexture, texCoord.xy);
+  vec4 rSrc = texture(uTexture, vec2(texCoord.x + offset / uSize.x * sin(piTime), texCoord.y));
+  float r = rSrc.a;
+
+  vec4 gSrc = texture(uTexture, vec2(texCoord.x + offset / uSize.x * sin(piTime + PI), texCoord.y));
+  float g = gSrc.a;
+
+  vec4 bSrc = texture(uTexture, vec2(texCoord.x, texCoord.y + offset / uSize.y * sin(piTime + PI * 0.66)));
+  float b = bSrc.a;
+  fragColor = vec4(r, g, b, clamp(r+g+b, 0.0, 1.0));    
+}

experimental/varfont_shader_puzzle/shaders/nothing.frag

@@ -0,0 +1,19 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize;
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  fragColor = texture(uTexture, texCoord);
+}

experimental/varfont_shader_puzzle/shaders/row_offset.frag

@@ -0,0 +1,35 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize;
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  
+  float levels = 5;
+  float maxMag = 0.1;
+  float minMag = 0.02;
+  float magMod = maxMag / levels;
+  float row = floor(texCoord.y * uSize.y * 0.25); // resolution/density of rows
+  float offsetDir = mod(row, 2) == 0 ? -1 : 1;
+  float sinFn = cos(texCoord.y * 1 * PI + piTime);
+  float offset = (offsetDir * (minMag + maxMag * sinFn)) * uDampener;
+
+  vec2 offsetTexCoord = vec2(texCoord.x + offset, texCoord.y);
+  vec4 outColor = texture(uTexture, offsetTexCoord);
+  if (texCoord.x + offset < 0.0 || texCoord.x + offset > 1.0) {
+    outColor = vec4(0.0, 0.0, 0.0, 0.0);
+  }
+  fragColor = outColor;
+}

experimental/varfont_shader_puzzle/shaders/wavy.frag

@@ -0,0 +1,30 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize; 
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  int speed;
+  
+  // wavy
+  speed = 1;
+  float xAdj = texCoord.x * 3 * PI;
+  float waveFnVal = sin((xAdj + piTime * speed));
+  float hackAdj = 0.0; 
+  float offset = ( ((pow(waveFnVal, 2) * 0.5 - 0.5) * 0.2) + hackAdj ) * uDampener;
+
+  vec2 offsetTexCoord = vec2(texCoord.x, texCoord.y + offset);
+  fragColor = texture(uTexture, offsetTexCoord);
+}

experimental/varfont_shader_puzzle/shaders/wavy2.frag

@@ -0,0 +1,26 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize;
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  float maxMag = 0.2;
+
+  float thisMag = (sin(texCoord.y * 10 + piTime) + 1) * 0.5 * maxMag * uDampener;
+  float srcX;
+  srcX = texCoord.x + (0.5 - texCoord.x) * thisMag;
+  vec2 srcCoord = vec2(srcX, texCoord.y);
+  fragColor = texture(uTexture, srcCoord);
+}

experimental/varfont_shader_puzzle/shaders/wavy_circ.frag

@@ -0,0 +1,38 @@
+// Copyright 2023 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#define PI 3.1415926538
+
+layout(location = 0) uniform float uTime;
+layout(location = 1) uniform vec2 uSize;
+layout(location = 3) uniform float uDampener;
+
+layout(location = 0) out vec4 fragColor;
+
+layout(location = 2) uniform sampler2D uTexture;
+
+void main()
+{
+  float piTime = uTime * PI * 2;
+  
+  vec2 texCoord = gl_FragCoord.xy / uSize.xy;
+  float maxMag = 0.4;
+  float minMag = 0.3;
+  float numRings = 6.0;
+  float ringVel = 4.0;
+  float numPeakShifts = 8.0;
+  float peakShiftVel = -3.0;
+
+  float unitX = (texCoord.x - 0.5) * 2;
+  float unitY = (texCoord.y - 0.5) * 2;
+  float dist = distance(vec2(0, 0), vec2(unitX, unitY));
+  float theta = atan(unitY, unitX) + PI; // add PI for atan2 values -PI to PI
+  float thisMag = (sin(theta * numRings - piTime * ringVel) + 1) * 0.5 * (cos(theta * numPeakShifts - piTime * peakShiftVel) + 1) * 0.5 * (maxMag - minMag) + minMag;
+
+  float unitSrcDist = dist - dist * thisMag;
+  float unitSrcX = cos(theta) * unitSrcDist;
+  float unitSrcY = sin(theta) * unitSrcDist;
+  float texSrcX = unitSrcX * 0.5 + 0.5;
+  float texSrcY = unitSrcY * 0.5 + 0.5;  
+  fragColor = texture(uTexture, vec2(texSrcX, texSrcY));
+}