blend modes on bind, workaround for the clear bug (just shove a quad there in replace mode)

libstarlight/source/starlight/datatypes/Color.cpp

@@ -1,9 +1,13 @@
 #include "Color.h"
 
+#include <limits>
+
 #include "starlight/_incLib/json.hpp"
 
 using starlight::Color;
 
+const Color Color::invalid = Color(std::numeric_limits<double>::quiet_NaN(), std::numeric_limits<double>::quiet_NaN(), std::numeric_limits<double>::quiet_NaN(), std::numeric_limits<double>::quiet_NaN());
+
 const Color Color::transparent = Color(0.0f, 0.0f, 0.0f, 0.0f);
 const Color Color::white = Color(1.0f, 1.0f, 1.0f);
 const Color Color::black = Color(0.0f, 0.0f, 0.0f);

libstarlight/source/starlight/datatypes/Color.h

@@ -25,11 +25,17 @@ namespace starlight {
         inline bool operator != (const Color& o) const { return r != o.r || g != o.g || b != o.b || a != o.a; }
         
         inline Color operator * (const Color& o) const { return Color(r * o.r, g * o.g, b * o.b, a * o.a); }
+        //inline Color operator * (const float m) const { return Color(r * m, g * m, b * m, a * m); }
         
         // hmm. I guess this will do ¯\_(ツ)_/¯ don't really want to force cstdint
         inline operator unsigned int() const { return (((((int)(a*255))&0xFF)<<24) | ((((int)(b*255))&0xFF)<<16) | ((((int)(g*255))&0xFF)<<8) | ((((int)(r*255))&0xFF)<<0)); }
         // premult: inline operator unsigned int() const { return (((((int)(a*255))&0xFF)<<24) | ((((int)(a*b*255))&0xFF)<<16) | ((((int)(a*g*255))&0xFF)<<8) | ((((int)(a*r*255))&0xFF)<<0)); }
         
+        inline bool Valid() const { return a == a && r == r && g == g && b == b; }
+        inline explicit operator bool() const { return a == a && r == r && g == g && b == b; }
+        
+        static const Color invalid;
+        
         static const Color transparent;
         static const Color white;
         static const Color black;

libstarlight/source/starlight/datatypes/Vector2.h

@@ -48,6 +48,7 @@ namespace starlight {
         inline Vector2 & operator -= (const Vector2 & o) { x -= o.x; y -= o.y; return *this; }
         inline Vector2 & operator *= (const Vector2 & o) { x *= o.x; y *= o.y; return *this; }
 
+        inline bool Valid() const { return x == x && y == y; }
         inline explicit operator bool() const { return x == x && y == y; }
         
         static const Vector2 invalid;

libstarlight/source/starlight/gfx/RenderCore.cpp

@@ -16,6 +16,7 @@ using starlight::Vector2;
 using starlight::VRect;
 using starlight::Color;
 using starlight::util::WorkerThread;
+using starlight::gfx::BlendMode;
 using starlight::gfx::CTexture;
 using starlight::gfx::CRenderTarget;
 using starlight::gfx::RenderCore;
@@ -144,25 +145,49 @@ void RenderCore::EndFrame() {
     C3D_FrameEnd(0);
 }
 
-void RenderCore::BindTexture(C3D_Tex* tex, const Color& color) {
+namespace {
+    void ApplyBlendMode(C3D_TexEnv* env, BlendMode mode) {
+        switch(mode) {
+            case BlendMode::Mask: // TODO: actually implement masking! this is just a copy of Blend right now
+                C3D_TexEnvOp(env, C3D_RGB, 0, 0, 0);
+                C3D_TexEnvOp(env, C3D_Alpha, GPU_TEVOP_A_SRC_ALPHA, GPU_TEVOP_A_SRC_ALPHA, 0);
+                C3D_TexEnvFunc(env, C3D_RGB, GPU_MODULATE);
+                C3D_TexEnvFunc(env, C3D_Alpha, GPU_MODULATE);
+                break;
+            
+            case BlendMode::Replace:
+                C3D_AlphaBlend(GPU_BLEND_MAX, GPU_BLEND_MAX, GPU_ONE, GPU_ZERO, GPU_ONE, GPU_ZERO); // flat replace
+                C3D_TexEnvOp(env, C3D_RGB, 0, 0, 0);
+                C3D_TexEnvOp(env, C3D_Alpha, GPU_TEVOP_A_SRC_ALPHA, GPU_TEVOP_A_SRC_ALPHA, 0);
+                C3D_TexEnvFunc(env, C3D_RGB, GPU_REPLACE);
+                C3D_TexEnvFunc(env, C3D_Alpha, GPU_REPLACE);
+                break;
+            
+            default:
+            case BlendMode::Blend:
+                C3D_AlphaBlend(GPU_BLEND_ADD, GPU_BLEND_ADD, GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA, GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA); // premult
+                C3D_TexEnvOp(env, C3D_RGB, 0, 0, 0);
+                C3D_TexEnvOp(env, C3D_Alpha, GPU_TEVOP_A_SRC_ALPHA, GPU_TEVOP_A_SRC_ALPHA, 0); // for color, the second op was 0... but that's the same value so whatever
+                C3D_TexEnvFunc(env, C3D_RGB, GPU_MODULATE); // and for color, this was REPLACE, not sure if that actually matters
+                C3D_TexEnvFunc(env, C3D_Alpha, GPU_MODULATE);
+                break;
+        }
+    }
+}
+
+void RenderCore::BindTexture(C3D_Tex* tex, const Color& color, BlendMode mode) {
     C3D_TexBind(0, tex); // 0 should be correct
     
     C3D_TexEnv* env = C3D_GetTexEnv(0);
     C3D_TexEnvSrc(env, C3D_Both, GPU_TEXTURE0, GPU_CONSTANT, 0);
-    C3D_TexEnvOp(env, C3D_RGB, 0, 0, 0);
+    ApplyBlendMode(env, mode);
-    C3D_TexEnvOp(env, C3D_Alpha, GPU_TEVOP_A_SRC_ALPHA, GPU_TEVOP_A_SRC_ALPHA, 0);
-    C3D_TexEnvFunc(env, C3D_RGB, GPU_MODULATE);//REPLACE); // let's see...
-    C3D_TexEnvFunc(env, C3D_Alpha, GPU_MODULATE);
     C3D_TexEnvColor(env, color.Premultiplied());
 }
 
-void RenderCore::BindColor(const Color& color) {
+void RenderCore::BindColor(const Color& color, BlendMode mode) {
     C3D_TexEnv* env = C3D_GetTexEnv(0);
     C3D_TexEnvSrc(env, C3D_Both, GPU_CONSTANT, 0, 0);
-    C3D_TexEnvOp(env, C3D_RGB, 0, 0, 0);
+    ApplyBlendMode(env, mode);
-    C3D_TexEnvOp(env, C3D_Alpha, GPU_TEVOP_A_SRC_ALPHA, 0, 0);
-    C3D_TexEnvFunc(env, C3D_RGB, GPU_REPLACE);//REPLACE); // let's see...
-    C3D_TexEnvFunc(env, C3D_Alpha, GPU_REPLACE);
     C3D_TexEnvColor(env, color.Premultiplied());
 }
 
@@ -263,7 +288,7 @@ CRenderTarget::CRenderTarget(int width, int height, bool forceExact) {
     //Clear(Color::transparent);
     //RenderCore::BindTexture(&tex, Color::white);
     //C3D_FrameBufClear(&(tgt->frameBuf), C3D_CLEAR_COLOR, 0, 0);
-    //C3D_RenderTargetSetClear(tgt, static_cast<C3D_ClearBits>(0), 0, 0);
+    C3D_RenderTargetSetClear(tgt, static_cast<C3D_ClearBits>(0), 0, 0);
 }
 
 CRenderTarget::~CRenderTarget() {
@@ -279,7 +304,7 @@ void CRenderTarget::Clear(Color color) {
 }
 
 void CRenderTarget::BindTarget() {
-    if (true || clearColor) { // clear if color valid
+    if (clearColor.Valid()) { // clear if color valid
         unsigned int c = clearColor;
         c = ((c>>24)&0x000000FF) | ((c>>8)&0x0000FF00) | ((c<<8)&0x00FF0000) | ((c<<24)&0xFF000000); // reverse endianness
         //C3D_RenderTargetSetClear(tgt, static_cast<C3D_ClearBits>(0), c, 0);
@@ -288,6 +313,13 @@ void CRenderTarget::BindTarget() {
     }
     C3D_FrameDrawOn(tgt);
     C3D_FVUnifMtx4x4(GPU_VERTEX_SHADER, sLocProjection, &projection);
+    
+    if (!firstClearDone) { firstClearDone = true; // workaround for faulty clearing; just draw a quad in replace mode to force the matter!
+        if (clearColor.Valid()) {
+            RenderCore::BindColor(clearColor, BlendMode::Replace);
+            RenderCore::DrawQuad(VRect(Vector2::zero, txSize), VRect::zero, false);
+        }
+    }
 }
 
 void CRenderTarget::Bind(Color color) {

libstarlight/source/starlight/gfx/RenderCore.h

@@ -14,6 +14,13 @@
 namespace starlight {
     namespace gfx {
         class RenderCore;
+        enum class BlendMode {
+            Blend,
+            Mask,
+            Replace,
+            
+            Normal = Blend
+        };
         
         class CTexture {
         protected:
@@ -33,6 +40,7 @@ namespace starlight {
             C3D_RenderTarget* tgt;
             C3D_Tex tex;
             Color clearColor = Color::transparent;
+            bool firstClearDone = false;
             
         public:
             C3D_Mtx projection;
@@ -62,8 +70,8 @@ namespace starlight {
             static void BeginFrame();
             static void EndFrame();
             
-            static void BindTexture(C3D_Tex* tex, const Color& color);
+            static void BindTexture(C3D_Tex* tex, const Color& color, BlendMode mode = BlendMode::Normal);
-            static void BindColor(const Color& color);
+            static void BindColor(const Color& color, BlendMode mode = BlendMode::Normal);
             static void DrawQuad(const VRect& rect, const VRect& src, bool noSnap = false);
             static void DrawQuad(const VRect& rect, const Vector2& anchor, float angle, const VRect& src);
             

libstarlight/todo.txt

@@ -2,7 +2,13 @@
 
 
 roadmap to v0.5.1 {
-    figure out how to fix the clear bug
+    - clear bug workaround implemented
+    ^ maybe replace clearing with the workaround entirely?
+    implement more blend modes {
+        - flat replace
+        masking
+    }
+    
     - fix the hang on osk when pressing (L|R)+up+left
     figure out what (else) to put on the left side of the keyboard (opposite backspace and enter)
     temporary drawable loading, local themeref, discard etc.
@@ -24,6 +30,7 @@ roadmap to v0.5.1 {
     }
 } then by v0.5.5 {
     event propagation system of some sort; threadsafe to whatever extent is needed on 3DS
+    figure out how to *actually* fix the clear bug...?
 } then consider these before 1.0 "gold" {
     make closing forms a bit less finicky (add them to a separate list and let the Application remove them from the list)
     garbage collection for not-recently-used theme assets {