GUI: prepare for colors in the per-chan osc

CMakeLists.txt

@@ -495,6 +495,7 @@ src/gui/editing.cpp
 src/gui/editControls.cpp
 src/gui/effectList.cpp
 src/gui/findReplace.cpp
+src/gui/gradient.cpp
 src/gui/insEdit.cpp
 src/gui/log.cpp
 src/gui/mixer.cpp

src/gui/chanOsc.cpp

@@ -34,8 +34,9 @@ void FurnaceGUI::drawChanOsc() {
   }
   if (!chanOscOpen) return;
   ImGui::SetNextWindowSizeConstraints(ImVec2(64.0f*dpiScale,32.0f*dpiScale),ImVec2(scrW*dpiScale,scrH*dpiScale));
-  if (ImGui::Begin("Oscilloscope (per-channel)",&chanOscOpen,globalWinFlags)) {
+  if (ImGui::Begin("Oscilloscope (per-channel)",&chanOscOpen,globalWinFlags|((chanOscOptions)?0:ImGuiWindowFlags_NoTitleBar))) {
     bool centerSettingReset=false;
+    if (chanOscOptions) {
       if (ImGui::BeginTable("ChanOscSettings",3)) {
         ImGui::TableNextRow();
         ImGui::TableNextColumn();
@@ -64,6 +65,62 @@ void FurnaceGUI::drawChanOsc() {
         ImGui::EndTable();
       }
 
+      ImGui::Text("Gradient");
+
+      if (chanOscGradTex==NULL) {
+        chanOscGradTex=SDL_CreateTexture(sdlRend,SDL_PIXELFORMAT_ABGR8888,SDL_TEXTUREACCESS_STREAMING,chanOscGrad.width,chanOscGrad.height);
+
+        if (chanOscGradTex==NULL) {
+          logE("error while creating gradient texture! %s",SDL_GetError());
+        } else {
+          updateChanOscGradTex=true;
+        }
+      }
+
+      if (ImGui::BeginTable("ChanOscGradSet",2)) {
+        ImGui::TableSetupColumn("c0",ImGuiTableColumnFlags_WidthFixed);
+        ImGui::TableSetupColumn("c1",ImGuiTableColumnFlags_WidthStretch);
+
+        ImGui::TableNextRow();
+        ImGui::TableNextColumn();
+        if (chanOscGradTex!=NULL) {
+          if (updateChanOscGradTex) {
+            chanOscGrad.render();
+            if (SDL_UpdateTexture(chanOscGradTex,NULL,chanOscGrad.grad.get(),chanOscGrad.width*4)==0) {
+              updateChanOscGradTex=false;
+            } else {
+              logE("error while updating gradient texture! %s",SDL_GetError());
+            }
+          }
+
+          ImGui::ImageButton(chanOscGradTex,ImVec2(400.0f*dpiScale,400.0f*dpiScale));
+          ImVec2 gradLeft=ImGui::GetItemRectMin();
+          ImVec2 gradSize=ImGui::GetItemRectSize();
+          if (ImGui::IsItemClicked(ImGuiMouseButton_Right)) {
+            chanOscGrad.points.push_back(Gradient2DPoint(
+              (ImGui::GetMousePos().x-gradLeft.x)/gradSize.x,
+              (ImGui::GetMousePos().y-gradLeft.y)/gradSize.y
+            ));
+            updateChanOscGradTex=true;
+            logI("a point inserted");
+          }
+
+          ImVec2 oldCurPos=ImGui::GetCursorPos();
+          for (Gradient2DPoint& i: chanOscGrad.points) {
+            ImGui::SetCursorPos(ImVec2(gradLeft.x+i.x*gradSize.x,gradLeft.y+i.y*gradSize.y));
+            ImGui::Text("Here");
+          }
+          ImGui::SetCursorPos(oldCurPos);
+        }
+
+        ImGui::TableNextColumn();
+        if (ImGui::ColorEdit4("Background",(float*)&chanOscGrad.bgColor)) {
+          updateChanOscGradTex=true;
+        }
+
+        ImGui::EndTable();
+      }
+    }
 
     ImGui::PushStyleVar(ImGuiStyleVar_CellPadding,ImVec2(0.0f,0.0f));
     float availY=ImGui::GetContentRegionAvail().y;
@@ -232,6 +289,10 @@ void FurnaceGUI::drawChanOsc() {
         }
       }
       ImGui::EndTable();
+
+      if (ImGui::IsItemClicked(ImGuiMouseButton_Right)) {
+        chanOscOptions=!chanOscOptions;
+      }
     }
     ImGui::PopStyleVar();
   }

src/gui/gradient.cpp

@@ -0,0 +1,70 @@
+/**
+ * Furnace Tracker - multi-system chiptune tracker
+ * Copyright (C) 2021-2022 tildearrow and contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "gui.h"
+#include "imgui.h"
+#include <math.h>
+
+void Gradient2D::render() {
+  ImU32* g=grad.get();
+  ImU32 bgColorU=ImGui::ColorConvertFloat4ToU32(bgColor);
+
+  // 1. fill with background color
+  for (size_t i=0; i<width*height; i++) {
+    g[i]=bgColorU;
+  }
+
+  // 2. insert points
+  for (Gradient2DPoint& i: points) {
+    float pDistSquared=i.distance*i.distance;
+    printf("shading this point %f %f\n",i.x,i.y);
+    for (size_t j=0; j<height; j++) {
+      float jFloat=(float)j/(float)height;
+      float distY=jFloat-i.y;
+      for (size_t k=0; k<width; k++) {
+        float kFloat=(float)k/(float)width;
+        float distX=kFloat-i.x;
+        float distSquared=(distX*distX)+(distY*distY);
+
+        if (distSquared>=pDistSquared) continue;
+
+        float dist=(1.0-(sqrt(distSquared)/i.distance))-i.spread;
+        if (dist<0) dist=0;
+        if (dist>1) dist=1;
+
+        ImU32 shadeColor=ImGui::ColorConvertFloat4ToU32(
+          ImVec4(
+            i.color.x*i.color.w*dist,
+            i.color.y*i.color.w*dist,
+            i.color.z*i.color.w*dist,
+            1.0f
+          )
+        );
+
+        ImU32 origColor=g[j*width+k];
+        g[j*width+k]=(
+          (MIN(  0xff,    (origColor&0xff)  +  (shadeColor&0xff)  )) | // R
+          (MIN( 0xff00,  (origColor&0xff00) + (shadeColor&0xff00) )) | // G
+          (MIN(0xff0000,(origColor&0xff0000)+(shadeColor&0xff0000))) | // B
+          (origColor&0xff000000)                                       // A
+        );
+      }
+    }
+  }
+}

src/gui/gui.cpp

@@ -4575,6 +4575,10 @@ FurnaceGUI::FurnaceGUI():
   chanOscCols(3),
   chanOscWindowSize(20.0f),
   chanOscWaveCorr(true),
+  chanOscOptions(false),
+  updateChanOscGradTex(true),
+  chanOscGrad(64,64),
+  chanOscGradTex(NULL),
   followLog(true),
 #ifdef IS_MOBILE
   pianoOctaves(7),
@@ -4664,4 +4668,6 @@ FurnaceGUI::FurnaceGUI():
   memset(queryReplaceEffectVal,0,sizeof(int)*8);
   memset(queryReplaceEffectDo,0,sizeof(bool)*8);
   memset(queryReplaceEffectValDo,0,sizeof(bool)*8);
+
+  chanOscGrad.bgColor=ImVec4(0.0f,0.0f,0.0f,1.0f);
 }

src/gui/gui.h

@@ -31,6 +31,7 @@
 #include <initializer_list>
 #include <map>
 #include <future>
+#include <memory>
 #include <mutex>
 #include <tuple>
 #include <vector>
@@ -757,6 +758,45 @@ struct TouchPoint {
     z(pressure) {}
 };
 
+struct Gradient2DPoint {
+  ImVec4 color;
+  float x, y;
+  float spread, distance;
+  bool selected, grab;
+  Gradient2DPoint(float xPos, float yPos):
+    color(1,1,1,1),
+    x(xPos),
+    y(yPos),
+    spread(0.0f),
+    distance(0.5f),
+    selected(false),
+    grab(false) {}
+  Gradient2DPoint():
+    color(1,1,1,1),
+    x(0.0f),
+    y(0.0f),
+    spread(0.0f),
+    distance(0.5f),
+    selected(false),
+    grab(false) {}
+};
+
+struct Gradient2D {
+  ImVec4 bgColor;
+  std::vector<Gradient2DPoint> points;
+  std::unique_ptr<ImU32[]> grad;
+  size_t width, height;
+
+  void render();
+  ImU32 get(float x, float y);
+  Gradient2D(size_t w, size_t h):
+    bgColor(0.0f,0.0f,0.0f,0.0f),
+    width(w),
+    height(h) {
+    grad=std::make_unique<ImU32[]>(width*height);
+  }
+};
+
 struct FurnaceGUISysDef {
   const char* name;
   std::vector<int> definition;
@@ -1344,7 +1384,9 @@ class FurnaceGUI {
   // per-channel oscilloscope
   int chanOscCols;
   float chanOscWindowSize;
-  bool chanOscWaveCorr;
+  bool chanOscWaveCorr, chanOscOptions, updateChanOscGradTex;
+  Gradient2D chanOscGrad;
+  SDL_Texture* chanOscGradTex;
   float chanOscLP0[DIV_MAX_CHANS];
   float chanOscLP1[DIV_MAX_CHANS];
   unsigned short lastNeedlePos[DIV_MAX_CHANS];