[update] Implemented a glitch effect for TextProgram.

src/sj/SelectScene.d

@@ -3,6 +3,7 @@ module sj.SelectScene;
 
 import std.conv,
        std.math,
+       std.random,
        std.variant;
 
 import derelict.sfml2.audio;
@@ -113,6 +114,13 @@ private abstract class AbstractSceneState {
   enum LoadingCubeRotationSpeed = vec3(0, PI/5, PI/10);
   enum LoadingCubeInterval      = 0.06;
 
+  enum TitleTextSize        = 40;
+  enum TitleTextScale       = vec3(-0.002, 0.002, 0.002);
+  enum TitleTextTranslation = vec3(0, -0.4, 0);
+
+  enum TitleTextRandomTranslationRange = 0.02;
+  enum TitleTextRandomScaleRange       = 0.0003;
+
   this(SelectScene owner) {
     owner_ = owner;
   }
@@ -212,14 +220,23 @@ private class SongAppearState : AbstractSceneState {
     const song = owner.songs_[song_index_];
     with (owner.text_) {
       const w = LoadGlyphs(vec2i(256, 64),
-          song.name.to!dstring, vec2i(40, 0), owner.fonts_.gothic);
+          song.name.to!dstring, vec2i(TitleTextSize, 0), owner.fonts_.gothic);
-      matrix.scale       = vec3(-0.002, 0.002, 0.002);
+      matrix.scale       = TitleTextScale;
-      matrix.translation = vec3(-w/2*matrix.scale.x, -0.4, 0);
+      matrix.translation = TitleTextTranslation + vec3(-w/2*matrix.scale.x, 0, 0);
     }
   }
   override UpdateResult Update(KeyInput input) {
     const ratio = anime_.Update();
 
+    if (owner.text_.frame++%10 > 7) {
+      alias RT = TitleTextRandomTranslationRange;
+      owner.text_.matrix.translation += vec3(
+          uniform(-RT, RT), uniform(-RT, RT), uniform(-RT, RT));
+      alias RS = TitleTextRandomScaleRange;
+      owner.text_.matrix.scale += vec3(
+          uniform(-RS, RS), uniform(-RS, RS), 0);
+    }
+
     with (owner.lobby_) {
       cube_matrix.rotation += cube_rota_speed_ease_.Calculate(ratio);
       cube_interval         = cube_interval_ease_.Calculate(ratio);
@@ -260,10 +277,35 @@ private class SongWaitState : AbstractSceneState {
 
     auto song = owner.songs_[song_index_];
     song.PlayForPreview();
+
+    with (owner.text_) {
+      matrix.scale       = TitleTextScale;
+      matrix.translation =
+        TitleTextTranslation + vec3(-modelWidth/2*matrix.scale.x, 0, 0);
+      frame = 0;
+    }
+    frame_ = 0;
   }
   override UpdateResult Update(KeyInput input) {
     owner.lobby_.cube_matrix.rotation += CubeRotationSpeed;
 
+    if (frame_%10 == 0) with (owner.text_) {
+      ++frame;
+
+      if (frame_%100 == 0) {
+        matrix.scale = TitleTextScale;
+        matrix.translation =
+          TitleTextTranslation + vec3(-modelWidth/2*matrix.scale.x, 0, 0);
+
+      } else if (frame_%20 == 0) {
+        alias RT = TitleTextRandomTranslationRange;
+        matrix.translation += vec3(uniform(-RT, RT), uniform(-RT, RT), uniform(-RT, RT));
+
+        alias RS = TitleTextRandomScaleRange;
+        matrix.scale += vec3(uniform(-RS, RS), uniform(-RS, RS), 0);
+      }
+    }
+
     if (input.right) {
       song.StopPlaying();
       song_appear_state_.Initialize(++song_index_%owner.songs_.length);
@@ -274,6 +316,8 @@ private class SongWaitState : AbstractSceneState {
       owner.title_scene_.Initialize();
       return CreateResult(owner.title_scene_);
     }
+
+    ++frame_;
     return CreateResult(this);
   }
 
@@ -285,4 +329,6 @@ private class SongWaitState : AbstractSceneState {
   SongAppearState song_appear_state_;
 
   size_t song_index_;
+
+  int frame_;
 }

src/sj/Text.d

@@ -44,8 +44,8 @@ class Text {
     gloader.pxHeight = charsz.y;
     gloader.flags    = FT_LOAD_DEFAULT | FT_LOAD_RENDER;
 
-    int   bmp_width;
+    model_width_ = 0;
-    float text_width = 0;
+    int bmp_width;
     foreach (c; text) {
       with (gloader) {
         character = c;
@@ -60,7 +60,7 @@ class Text {
       const bearing_y = m.horiBearingY*1f / m.height * srcsz.y;
       const advance   = m.horiAdvance *1f / m.width  * srcsz.x;
 
-      const posleft   = text_width + bearing_x;
+      const posleft   = model_width_ + bearing_x;
       const posright  = posleft + srcsz.x;
       const postop    = bearing_y;
       const posbottom = postop - srcsz.y;
@@ -94,8 +94,8 @@ class Text {
       *vertices_ptr++ = uvright;
       *vertices_ptr++ = uvbottom;
 
-      bmp_width  += srcsz.x;
+      bmp_width    += srcsz.x;
-      text_width += advance;
+      model_width_ += advance;
     }
 
     texture_.Bind();
@@ -133,7 +133,7 @@ class Text {
     }
     index_count_ = indices_ptr - indices_data.entity;
 
-    return text_width;
+    return model_width_;
   }
 
   ///
@@ -145,17 +145,25 @@ class Text {
   void Draw(mat4 proj, mat4 view) {
     if (index_count_ == 0) return;
 
-    program_.Use(proj, view, matrix.Create(), texture_, color);
+    program_.Use(proj, view,
+        matrix.Create(), texture_, color, frame, model_width_);
 
     vao_.Bind();
     indices_.Bind();
     gl.DrawElements(GL_TRIANGLE_STRIP, index_count_.to!int, GL_UNSIGNED_SHORT, null);
   }
 
+  ///
+  @property float modelWidth() const {
+    return model_width_;
+  }
+
   ///
   ModelMatrixFactory!4 matrix;
   ///
   vec4 color = vec4(0, 0, 0, 1);
+  ///
+  int frame;
 
  private:
   static void CopyRawPixels(in ubyte* src, vec2i srcsz, ubyte* dst, vec2i dstsz, vec2i offset) {
@@ -179,4 +187,6 @@ class Text {
   ElementArrayBufferRef indices_;
 
   size_t index_count_;
+
+  float model_width_;
 }

src/sj/TextProgram.d

@@ -28,10 +28,12 @@ class TextProgram {
     layout(location = 0) in vec3 vert;
     layout(location = 1) in vec2 uv;
 
+    out vec3 vert_;
     out vec2 uv_;
 
     void main() {
-      uv_ = uv;
+      vert_ = vert;
+      uv_   = uv;
       gl_Position = P * V * M * vec4(vert, 1);
     }
   };
@@ -39,14 +41,44 @@ class TextProgram {
   enum FragmentShaderSrc = ShaderHeader ~ q{
     layout(location = 3) uniform sampler2D tex;
     layout(location = 4) uniform vec4      color;
+    layout(location = 5) uniform int       frame;
+    layout(location = 6) uniform float     model_width;
 
+    in vec3 vert_;
     in vec2 uv_;
 
     out vec4 pixel_;
 
+    float choose(int a, int b, float a_big, float b_big) {
+      float condition = step(float(a), float(b));
+      return condition * b_big + (1-condition) * a_big;
+    }
+    float choose(float a, float b, float c, float hit, float other) {
+      float condition = step(a, b) * step(b, c);
+      return condition * hit + (1-condition) * other;
+    }
+
     void main() {
+      float vx = vert_.x / model_width;
+      vec2  uv = uv_;
+
+      uv.y = choose(15, frame%18, uv.y,
+          choose(0.1, vx, 0.2, clamp(uv.y, 0, 0.6), uv.y));
+      uv.y = choose(8, frame%14, uv.y,
+          choose(0.1, vx, 0.6, clamp(uv.y, 0, 0.8), uv.y));
+      uv.y = choose(21, frame%29, uv.y,
+          choose(0.2, vx, 0.3, clamp(uv.y, 0.1, 1), uv.y));
+      uv.y = choose(20, frame%23, uv.y,
+          choose(0.4, vx, 0.6, clamp(uv.y, 0.4, 1), uv.y));
+      uv.y = choose(5, frame%6, uv.y,
+          choose(0.5, vx, 0.8, clamp(uv.y, 0, 0.7), uv.y));
+      uv.y = choose(15, frame%17, uv.y,
+          choose(0.6, vx, 0.7, clamp(uv.y, 0.5, 1), uv.y));
+      uv.y = choose(7, frame%9, uv.y,
+          choose(0.6, vx, 0.9, clamp(uv.y, 0.3, 1), uv.y));
+
       pixel_    = color;
-      pixel_.a *= texture(tex, uv_).r;
+      pixel_.a *= texture(tex, uv).r;
     }
   };
 
@@ -89,7 +121,8 @@ class TextProgram {
   }
 
   ///
-  void Use(mat4 proj, mat4 view, mat4 model, ref Texture2DRef tex, vec4 color) {
+  void Use(mat4 proj, mat4 view, mat4 model,
+      ref Texture2DRef tex, vec4 color, int frame, float model_width) {
     tex.BindToUnit(GL_TEXTURE0);
     sampler_.Bind(0);
 
@@ -99,6 +132,8 @@ class TextProgram {
     program_.uniform!2 = model;
     program_.uniform!3 = 0;
     program_.uniform!4 = color;
+    program_.uniform!5 = frame;
+    program_.uniform!6 = model_width;
   }
 
  private: