Merge pull request #56 from dougbinks/NVGcolor

Merged NVGcolor, which implements the color as floats, colors can be > 1.0, allowing HDR rendering when needed.

example/demo.c

@@ -24,6 +24,16 @@
 #define ICON_LOGIN 0xE740
 #define ICON_TRASH 0xE729
 
+// Returns 1 if col.rgba is 0.0f,0.0f,0.0f,0.0f, 0 otherwise
+int isBlack( struct NVGcolor col )
+{
+	if( col.r == 0.0f && col.g == 0.0f && col.b == 0.0f && col.a == 0.0f )
+	{
+		return 1;
+	}
+	return 0;
+}
+
 static char* cpToUTF8(int cp, char* str)
 {
 	int n = 0;
@@ -254,17 +264,17 @@ void drawCheckBox(struct NVGcontext* vg, const char* text, float x, float y, flo
 	nvgText(vg, x+9+2, y+h*0.5f, cpToUTF8(ICON_CHECK,icon), NULL);
 }
 
-void drawButton(struct NVGcontext* vg, int preicon, const char* text, float x, float y, float w, float h, unsigned int col)
+void drawButton(struct NVGcontext* vg, int preicon, const char* text, float x, float y, float w, float h, struct NVGcolor col)
 {
 	struct NVGpaint bg;
 	char icon[8];
 	float cornerRadius = 4.0f;
 	float tw = 0, iw = 0;
 
-	bg = nvgLinearGradient(vg, x,y,x,y+h, nvgRGBA(255,255,255,col==0?16:32), nvgRGBA(0,0,0,col==0?16:32));
+	bg = nvgLinearGradient(vg, x,y,x,y+h, nvgRGBA(255,255,255,isBlack(col)?16:32), nvgRGBA(0,0,0,isBlack(col)?16:32));
 	nvgBeginPath(vg);
 	nvgRoundedRect(vg, x+1,y+1, w-2,h-2, cornerRadius-1);
-	if (col != 0) {
+	if (!isBlack(col)) {
 		nvgFillColor(vg, col);
 		nvgFill(vg);
 	}

src/nanovg.c

@@ -278,35 +278,57 @@ void nvgEndFrame(struct NVGcontext* ctx)
 	ctx->params.renderFlush(ctx->params.userPtr, ctx->alphaBlend);
 }
 
-unsigned int nvgRGB(unsigned char r, unsigned char g, unsigned char b)
+struct NVGcolor nvgRGB(unsigned char r, unsigned char g, unsigned char b)
 {
 	return nvgRGBA(r,g,b,255);
 }
 
-unsigned int nvgRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
+struct NVGcolor nvgRGBf(float r, float g, float b)
 {
-	return (r) | (g << 8) | (b << 16) | (a << 24);
+	return nvgRGBAf(r,g,b,1.0f);
 }
 
-unsigned int nvgTransRGBA(unsigned int c, unsigned char a)
+struct NVGcolor nvgRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
 {
-	int r = (c) & 0xff;
-	int g = (c>>8) & 0xff;
-	int b = (c>>16) & 0xff;
-	return nvgRGBA(r,g,b,a);
+	struct NVGcolor color = {r/255.0f, g/255.0f, b/255.0f, a/255.0f};
+	return color;
 }
 
-unsigned int nvgLerpRGBA(unsigned int c0, unsigned int c1, float u)
+struct NVGcolor nvgRGBAf(float r, float g, float b, float a)
 {
-	int iu = (int)(nvg__clampf(u, 0.0f, 1.0f) * 256.0f);
-	int r = (((c0) & 0xff)*(256-iu) + (((c1) & 0xff)*iu)) >> 8;
-	int g = (((c0>>8) & 0xff)*(256-iu) + (((c1>>8) & 0xff)*iu)) >> 8;
-	int b = (((c0>>16) & 0xff)*(256-iu) + (((c1>>16) & 0xff)*iu)) >> 8;
-	int a = (((c0>>24) & 0xff)*(256-iu) + (((c1>>24) & 0xff)*iu)) >> 8;
-	return nvgRGBA(r,g,b,a);
+	struct NVGcolor color = {r, g, b, a};
+	return color;
 }
 
-unsigned int nvgHSL(float h, float s, float l)
+struct NVGcolor nvgTransRGBA(struct NVGcolor c, unsigned char a)
+{
+	c.a = a / 255.0f;
+	return c;
+}
+
+struct NVGcolor nvgTransRGBAf(struct NVGcolor c, float a)
+{
+	c.a = a;
+	return c;
+}
+
+struct NVGcolor nvgLerpRGBA(struct NVGcolor c0, struct NVGcolor c1, float u)
+{
+	int i;
+	float oneminu;
+	struct NVGcolor cint;
+
+	u = nvg__clampf(u, 0.0f, 1.0f);
+	oneminu = 1.0f - u;
+	for( i = 0; i <4; ++i )
+	{
+		cint.rgba[i] = c0.rgba[i] * oneminu + c1.rgba[i] * u;
+	}
+	 
+	return cint;
+}
+
+struct NVGcolor nvgHSL(float h, float s, float l)
 {
 	return nvgHSLA(h,s,l,255);
 }
@@ -324,23 +346,25 @@ static float nvg__hue(float h, float m1, float m2)
 	return m1;
 }
 
-unsigned int nvgHSLA(float h, float s, float l, unsigned char a)
+struct NVGcolor nvgHSLA(float h, float s, float l, unsigned char a)
 {
 	float m1, m2;
-	unsigned char r,g,b;
+	struct NVGcolor col;
 	h = nvg__modf(h, 1.0f);
 	if (h < 0.0f) h += 1.0f;
 	s = nvg__clampf(s, 0.0f, 1.0f);
 	l = nvg__clampf(l, 0.0f, 1.0f);
 	m2 = l <= 0.5f ? (l * (1 + s)) : (l + s - l * s);
 	m1 = 2 * l - m2;
-	r = (unsigned char)nvg__clampf(nvg__hue(h + 1.0f/3.0f, m1, m2) * 255.0f, 0, 255);
-	g = (unsigned char)nvg__clampf(nvg__hue(h, m1, m2) * 255.0f, 0, 255);
-	b = (unsigned char)nvg__clampf(nvg__hue(h - 1.0f/3.0f, m1, m2) * 255.0f, 0, 255);
-	return nvgRGBA(r,g,b,a);
+	col.r = nvg__clampf(nvg__hue(h + 1.0f/3.0f, m1, m2), 0.0f, 1.0f);
+	col.g = nvg__clampf(nvg__hue(h, m1, m2), 0.0f, 1.0f);
+	col.b = nvg__clampf(nvg__hue(h - 1.0f/3.0f, m1, m2), 0.0f, 1.0f);
+	col.a = a/255.0f;
+	return col;
 }
 
 
+
 static struct NVGstate* nvg__getState(struct NVGcontext* ctx)
 {
 	return &ctx->states[ctx->nstates-1];
@@ -396,7 +420,7 @@ static void nvg__xformPremultiply(float* t, float* s)
 	memcpy(t, s2, sizeof(float)*6);
 }
 
-static void nvg__setPaintColor(struct NVGpaint* p, unsigned int color)
+static void nvg__setPaintColor(struct NVGpaint* p, struct NVGcolor color)
 {
 	memset(p, 0, sizeof(*p));
 	nvg__xformIdentity(p->xform);
@@ -511,7 +535,7 @@ void nvgScale(struct NVGcontext* ctx, float x, float y)
 }
 
 
-void nvgStrokeColor(struct NVGcontext* ctx, unsigned int color)
+void nvgStrokeColor(struct NVGcontext* ctx, struct NVGcolor color)
 {
 	struct NVGstate* state = nvg__getState(ctx);
 	nvg__setPaintColor(&state->stroke, color);
@@ -524,7 +548,7 @@ void nvgStrokePaint(struct NVGcontext* ctx, struct NVGpaint paint)
 	nvg__xformMultiply(state->stroke.xform, state->xform);
 }
 
-void nvgFillColor(struct NVGcontext* ctx, unsigned int color)
+void nvgFillColor(struct NVGcontext* ctx, struct NVGcolor color)
 {
 	struct NVGstate* state = nvg__getState(ctx);
 	nvg__setPaintColor(&state->fill, color);
@@ -587,7 +611,7 @@ void nvgDeleteImage(struct NVGcontext* ctx, int image)
 
 struct NVGpaint nvgLinearGradient(struct NVGcontext* ctx,
 								  float sx, float sy, float ex, float ey,
-								  unsigned int icol, unsigned int ocol)
+								  struct NVGcolor icol, struct NVGcolor ocol)
 {
 	struct NVGpaint p;
 	float dx, dy, d;
@@ -626,7 +650,7 @@ struct NVGpaint nvgLinearGradient(struct NVGcontext* ctx,
 
 struct NVGpaint nvgRadialGradient(struct NVGcontext* ctx,
 								  float cx, float cy, float inr, float outr,
-								  unsigned int icol, unsigned int ocol)
+								  struct NVGcolor icol, struct NVGcolor ocol)
 {
 	struct NVGpaint p;
 	float r = (inr+outr)*0.5f;
@@ -653,7 +677,7 @@ struct NVGpaint nvgRadialGradient(struct NVGcontext* ctx,
 
 struct NVGpaint nvgBoxGradient(struct NVGcontext* ctx,
 							   float x, float y, float w, float h, float r, float f,
-							   unsigned int icol, unsigned int ocol)
+							   struct NVGcolor icol, struct NVGcolor ocol)
 {
 	struct NVGpaint p;
 

src/nanovg.h

@@ -27,14 +27,26 @@ extern "C" {
 
 struct NVGcontext;
 
+struct NVGcolor
+{
+	union
+	{
+		float rgba[4];
+		struct
+		{
+			float r,g,b,a;
+		};
+	};
+};
+
 struct NVGpaint
 {
 	float xform[6];
 	float extent[2];
 	float radius;
 	float feather;
-	unsigned int innerColor;
-	unsigned int outerColor;
+	struct NVGcolor innerColor;
+	struct NVGcolor outerColor;
 	int image;
 	int repeat;
 };
@@ -101,25 +113,36 @@ void nvgEndFrame(struct NVGcontext* ctx);
 //
 // Colors in NanoVG are stored as unsigned ints in ABGR format.
 
-// Returns a color value from red, green, blue values. Alpha will be set to 255.
-unsigned int nvgRGB(unsigned char r, unsigned char g, unsigned char b);
+// Returns a color value from red, green, blue values. Alpha will be set to 255 (1.0f).
+struct NVGcolor nvgRGB(unsigned char r, unsigned char g, unsigned char b);
+
+// Returns a color value from red, green, blue values. Alpha will be set to 1.0f.
+struct NVGcolor nvgRGBf(float r, float g, float b);
+
 
 // Returns a color value from red, green, blue and alpha values.
-unsigned int nvgRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
+struct NVGcolor nvgRGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a);
+
+// Returns a color value from red, green, blue and alpha values.
+struct NVGcolor nvgRGBAf(float r, float g, float b, float a);
+
 
 // Linearly interpoaltes from color c0 to c1, and returns resulting color value.
-unsigned int nvgLerpRGBA(unsigned int c0, unsigned int c1, float u);
+struct NVGcolor nvgLerpRGBA(struct NVGcolor c0, struct NVGcolor c1, float u);
+
+// Sets transparency of a color value.
+struct NVGcolor nvgTransRGBA(struct NVGcolor c0, unsigned char a);
 
 // Sets transparency of a color value.
-unsigned int nvgTransRGBA(unsigned int c0, unsigned char a);
+struct NVGcolor nvgTransRGBAf(struct NVGcolor c0, float a);
 
 // Returns color value specified by hue, saturation and lightness.
 // HSL values are all in range [0..1], alpha will be set to 255.
-unsigned int nvgHSL(float h, float s, float l);
+struct NVGcolor nvgHSL(float h, float s, float l);
 
 // Returns color value specified by hue, saturation and lightness and alpha.
 // HSL values are all in range [0..1], alpha in range [0..255]
-unsigned int nvgHSLA(float h, float s, float l, unsigned char a);
+struct NVGcolor nvgHSLA(float h, float s, float l, unsigned char a);
 
 //
 // State Handling
@@ -148,13 +171,13 @@ void nvgReset(struct NVGcontext* ctx);
 // Current render style can be saved and restored using nvgSave() and nvgRestore(). 
 
 // Sets current stroke style to a solid color.
-void nvgStrokeColor(struct NVGcontext* ctx, unsigned int color);
+void nvgStrokeColor(struct NVGcontext* ctx, struct NVGcolor color);
 
 // Sets current stroke style to a paint, which can be a one of the gradients or a pattern.
 void nvgStrokePaint(struct NVGcontext* ctx, struct NVGpaint paint);
 
 // Sets current fill cstyle to a solid color.
-void nvgFillColor(struct NVGcontext* ctx, unsigned int color);
+void nvgFillColor(struct NVGcontext* ctx, struct NVGcolor color);
 
 // Sets current fill style to a paint, which can be a one of the gradients or a pattern.
 void nvgFillPaint(struct NVGcontext* ctx, struct NVGpaint paint);
@@ -247,7 +270,7 @@ void nvgDeleteImage(struct NVGcontext* ctx, int image);
 // of the linear gradient, icol specifies the start color and ocol the end color.
 // The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
 struct NVGpaint nvgLinearGradient(struct NVGcontext* ctx, float sx, float sy, float ex, float ey,
-								  unsigned int icol, unsigned int ocol);
+								  struct NVGcolor icol, struct NVGcolor ocol);
 
 // Creates and returns a box gradient. Box gradient is a feathered rounded rectangle, it is useful for rendering
 // drop shadows or hilights for boxes. Parameters (x,y) define the top-left corner of the rectangle,
@@ -255,13 +278,13 @@ struct NVGpaint nvgLinearGradient(struct NVGcontext* ctx, float sx, float sy, fl
 // the border of the rectangle is. Parameter icol specifies the inner color and ocol the outer color of the gradient.
 // The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
 struct NVGpaint nvgBoxGradient(struct NVGcontext* ctx, float x, float y, float w, float h,
-							   float r, float f, unsigned int icol, unsigned int ocol);
+							   float r, float f, struct NVGcolor icol, struct NVGcolor ocol);
 
 // Creates and returns a radial gradient. Parameters (cx,cy) specify the center, inr and outr specify
 // the inner and outer radius of the gradient, icol specifies the start color and ocol the end color.
 // The gradient is transformed by the current transform when it is passed to nvgFillPaint() or nvgStrokePaint().
 struct NVGpaint nvgRadialGradient(struct NVGcontext* ctx, float cx, float cy, float inr, float outr,
-								  unsigned int icol, unsigned int ocol);
+								  struct NVGcolor icol, struct NVGcolor ocol);
 
 // Creates and returns an image patter. Parameters (ox,oy) specify the left-top location of the image pattern,
 // (ex,ey) the size of one image, angle rotation around the top-left corner, image is handle to the image to render,

src/nanovg_gl2.h

@@ -516,14 +516,6 @@ static int glnvg__renderGetTextureSize(void* uptr, int image, int* w, int* h)
 	return 1;
 }
 
-static void glnvg__toFloatColor(float* fc, unsigned int c)
-{
-	fc[0] = ((c) & 0xff) / 255.0f;
-	fc[1] = ((c>>8) & 0xff) / 255.0f;
-	fc[2] = ((c>>16) & 0xff) / 255.0f;
-	fc[3] = ((c>>24) & 0xff) / 255.0f;
-}
-
 static void glnvg__xformIdentity(float* t)
 {
 	t[0] = 1.0f; t[1] = 0.0f;
@@ -562,15 +554,15 @@ static void glnvg__xformToMat3x3(float* m3, float* t)
 
 static int glnvg__setupPaint(struct GLNVGcontext* gl, struct NVGpaint* paint, struct NVGscissor* scissor, float width, float fringe)
 {
-	float innerCol[4];
-	float outerCol[4];
+	struct NVGcolor innerCol;
+	struct NVGcolor  outerCol;
 	struct GLNVGtexture* tex = NULL;
 	float invxform[6], paintMat[9], scissorMat[9];
 	float scissorx = 0, scissory = 0;
 	float scissorsx = 0, scissorsy = 0;
 
-	glnvg__toFloatColor(innerCol, paint->innerColor);
-	glnvg__toFloatColor(outerCol, paint->outerColor);
+	innerCol = paint->innerColor;
+	outerCol = paint->outerColor;
 
 	glnvg__xformInverse(invxform, paint->xform);
 	glnvg__xformToMat3x3(paintMat, invxform);
@@ -618,8 +610,8 @@ static int glnvg__setupPaint(struct GLNVGcontext* gl, struct NVGpaint* paint, st
 		glUniform2f(gl->shader.loc[GLNVG_LOC_EXTENT], paint->extent[0], paint->extent[1]);
 		glUniform1f(gl->shader.loc[GLNVG_LOC_RADIUS], paint->radius);
 		glUniform1f(gl->shader.loc[GLNVG_LOC_FEATHER], paint->feather);
-		glUniform4fv(gl->shader.loc[GLNVG_LOC_INNERCOL], 1, innerCol);
-		glUniform4fv(gl->shader.loc[GLNVG_LOC_OUTERCOL], 1, outerCol);
+		glUniform4fv(gl->shader.loc[GLNVG_LOC_INNERCOL], 1, innerCol.rgba);
+		glUniform4fv(gl->shader.loc[GLNVG_LOC_OUTERCOL], 1, outerCol.rgba);
 		glUniform1f(gl->shader.loc[GLNVG_LOC_STROKEMULT], (width*0.5f + fringe*0.5f)/fringe);
 		glnvg__checkError("grad paint loc");
 	}
@@ -850,7 +842,7 @@ static void glnvg__renderTriangles(void* uptr, struct NVGpaint* paint, struct NV
 {
 	struct GLNVGcontext* gl = (struct GLNVGcontext*)uptr;
 	struct GLNVGtexture* tex = glnvg__findTexture(gl, paint->image);
-	float color[4];
+	struct NVGcolor color;
 	NVG_NOTUSED(scissor);
 
 	if (gl->shader.prog == 0)
@@ -875,8 +867,8 @@ static void glnvg__renderTriangles(void* uptr, struct NVGpaint* paint, struct NV
 	glEnableVertexAttribArray(0);
 	glEnableVertexAttribArray(1);
 
-	glnvg__toFloatColor(color, paint->innerColor);
-	glVertexAttrib4fv(2, color);
+	color = paint->innerColor;
+	glVertexAttrib4fv(2, color.rgba);
 
 	glDrawArrays(GL_TRIANGLES, 0, nverts);
 

src/nanovg_gl3.h

@@ -522,14 +522,6 @@ static int glnvg__renderGetTextureSize(void* uptr, int image, int* w, int* h)
 	return 1;
 }
 
-static void glnvg__toFloatColor(float* fc, unsigned int c)
-{
-	fc[0] = ((c) & 0xff) / 255.0f;
-	fc[1] = ((c>>8) & 0xff) / 255.0f;
-	fc[2] = ((c>>16) & 0xff) / 255.0f;
-	fc[3] = ((c>>24) & 0xff) / 255.0f;
-}
-
 static void glnvg__xformIdentity(float* t)
 {
 	t[0] = 1.0f; t[1] = 0.0f;
@@ -568,15 +560,15 @@ static void glnvg__xformToMat3x3(float* m3, float* t)
 
 static int glnvg__setupPaint(struct GLNVGcontext* gl, struct NVGpaint* paint, struct NVGscissor* scissor, float width, float fringe)
 {
-	float innerCol[4];
-	float outerCol[4];
+	struct NVGcolor innerCol;
+	struct NVGcolor outerCol;
 	struct GLNVGtexture* tex = NULL;
 	float invxform[6], paintMat[9], scissorMat[9];
 	float scissorx = 0, scissory = 0;
 	float scissorsx = 0, scissorsy = 0;
 
-	glnvg__toFloatColor(innerCol, paint->innerColor);
-	glnvg__toFloatColor(outerCol, paint->outerColor);
+    innerCol = paint->innerColor;
+	outerCol = paint->outerColor;
 
 	glnvg__xformInverse(invxform, paint->xform);
 	glnvg__xformToMat3x3(paintMat, invxform);
@@ -624,8 +616,8 @@ static int glnvg__setupPaint(struct GLNVGcontext* gl, struct NVGpaint* paint, st
 		glUniform2f(gl->shader.loc[GLNVG_LOC_EXTENT], paint->extent[0], paint->extent[1]);
 		glUniform1f(gl->shader.loc[GLNVG_LOC_RADIUS], paint->radius);
 		glUniform1f(gl->shader.loc[GLNVG_LOC_FEATHER], paint->feather);
-		glUniform4fv(gl->shader.loc[GLNVG_LOC_INNERCOL], 1, innerCol);
-		glUniform4fv(gl->shader.loc[GLNVG_LOC_OUTERCOL], 1, outerCol);
+		glUniform4fv(gl->shader.loc[GLNVG_LOC_INNERCOL], 1, innerCol.rgba);
+		glUniform4fv(gl->shader.loc[GLNVG_LOC_OUTERCOL], 1, outerCol.rgba);
 		glUniform1f(gl->shader.loc[GLNVG_LOC_STROKEMULT], (width*0.5f + fringe*0.5f)/fringe);
 		glnvg__checkError("grad paint loc");
 	}
@@ -858,7 +850,7 @@ static void glnvg__renderTriangles(void* uptr, struct NVGpaint* paint, struct NV
 {
 	struct GLNVGcontext* gl = (struct GLNVGcontext*)uptr;
 	struct GLNVGtexture* tex = glnvg__findTexture(gl, paint->image);
-	float color[4];
+	struct NVGcolor color;
 	NVG_NOTUSED(scissor);
 
 	if (gl->shader.prog == 0)
@@ -884,8 +876,8 @@ static void glnvg__renderTriangles(void* uptr, struct NVGpaint* paint, struct NV
 	glEnableVertexAttribArray(0);
 	glEnableVertexAttribArray(1);
 
-	glnvg__toFloatColor(color, paint->innerColor);
-	glVertexAttrib4fv(2, color);
+	color = paint->innerColor;
+	glVertexAttrib4fv(2, color.rgba);
 
 	glDrawArrays(GL_TRIANGLES, 0, nverts);
 

src/nanovg_gl3buf.h

@@ -118,8 +118,8 @@ struct GLNVGpath {
 struct GLNVGfragUniforms {
    float scissorMat[12]; // matrices are actually 3 vec4s
    float paintMat[12];
-   float innerCol[4];
-   float outerCol[4];
+   struct NVGcolor innerCol;
+   struct NVGcolor  outerCol;
    float scissorExt[2];
    float scissorScale[2];
    float extent[2];
@@ -591,8 +591,8 @@ static int glnvg__convertPaint(struct GLNVGcontext* gl, struct GLNVGfragUniforms
 	struct GLNVGtexture* tex = NULL;
 	float invxform[6];
 
-	glnvg__toFloatColor(frag->innerCol, paint->innerColor);
-	glnvg__toFloatColor(frag->outerCol, paint->outerColor);
+	frag->innerCol = paint->innerColor;
+	frag->outerCol = paint->outerColor;
 
 	glnvg__xformInverse(invxform, paint->xform);
 	glnvg__xformToMat3x4(frag->paintMat, invxform);