add opengl support

[chaz/rasterize] / color.h

diff --git a/color.h b/color.h
index ba333e2c0f6d279fb42d48836e5113f8b7103c90..bbb32852f8201995709db87e2eafa50be231f482 100644 (file)
--- a/color.h
+++ b/color.h
@@ -5,8 +5,8 @@
  * mcgarvey@eng.utah.edu
  */
 
-#ifndef __COLOR_H__
-#define __COLOR_H__
+#ifndef _COLOR_H_
+#define _COLOR_H_
 
 #include "common.h"
 
@@ -32,7 +32,7 @@ typedef struct color color_t;
 /*
  * Initialize a color.
  */
-__fast__
+INLINE_MAYBE
 void color_init(color_t* c, colorchan_t r, colorchan_t g, colorchan_t b, colorchan_t a)
 {
     c->r = r;
@@ -45,7 +45,7 @@ void color_init(color_t* c, colorchan_t r, colorchan_t g, colorchan_t b, colorch
 /*
  * Create a new color, copied by value.
  */
-__fast__
+INLINE_MAYBE
 color_t color_new(colorchan_t r, colorchan_t g, colorchan_t b, colorchan_t a)
 {
     color_t c;
@@ -65,28 +65,137 @@ color_t color_new(colorchan_t r, colorchan_t g, colorchan_t b, colorchan_t a)
 
 
 /*
- * Define integer types for a 32-bit RGBA color representation.
+ * Get a pointer to the color data.
  */
-typedef uint32_t    rgba_t;
-typedef uint8_t     rgbachan_t;
+INLINE_MAYBE
+const scal_t* color_data(const color_t* c)
+{
+    return &c->r;
+}
+
 
 /*
- * Create a new color from a 32-bit RGBA value.
+ * Print the color to stdout.
  */
-__fast__
-color_t color_from_rgba(rgba_t n)
+INLINE_MAYBE
+void color_print(color_t c)
 {
-    colorchan_t r = (colorchan_t)UNPACK(n, 3) / S(255.0);
-    colorchan_t g = (colorchan_t)UNPACK(n, 2) / S(255.0);
-    colorchan_t b = (colorchan_t)UNPACK(n, 1) / S(255.0);
-    colorchan_t a = (colorchan_t)UNPACK(n, 0) / S(255.0);
-    return color_new(r, g, b, a);
+#if (SCALAR_SIZE == 8)
+    const char* fmt = "[ %9.5lf %9.5lf %9.5lf %9.5lf ]";
+#else
+    const char* fmt = "[ %9.5f %9.5f %9.5f %9.5f ]";
+#endif
+    printf(fmt, c.r, c.g, c.b, c.a);
+}
+
+
+/*
+ * Add two colors together.
+ */
+INLINE_MAYBE
+color_t color_add(color_t c1, color_t c2)
+{
+    return color_new(c1.r + c2.r, c1.g + c2.g, c1.b + c2.b, c1.a);
+}
+
+/*
+ * Add three colors together.
+ */
+INLINE_MAYBE
+color_t color_add2(color_t c1, color_t c2, color_t c3)
+{
+    return color_add(color_add(c1, c2), c3);
+}
+
+/*
+ * Multiply two colors together.
+ */
+INLINE_MAYBE
+color_t color_mult(color_t c1, color_t c2)
+{
+    c1.r *= c2.r;
+    c1.g *= c2.g;
+    c1.b *= c2.b;
+    return c1;
+}
+
+/*
+ * Scale a color by some scalar coefficient.
+ */
+INLINE_MAYBE
+color_t color_scale(color_t c, scal_t k)
+{
+    c.r *= k;
+    c.g *= k;
+    c.b *= k;
+    return c;
 }
 
+/*
+ * Scale a color by another color and some scalar coefficient.
+ */
+INLINE_MAYBE
+color_t color_scale2(color_t c1, color_t c2, scal_t k)
+{
+    return color_scale(color_mult(c1, c2), k);
+}
+
+INLINE_MAYBE
+color_t color_blend(color_t d, color_t s)
+{
+    d.r = (S(1.0) - s.a) * d.r + s.a * s.r;
+    d.g = (S(1.0) - s.a) * d.g + s.a * s.g;
+    d.b = (S(1.0) - s.a) * d.b + s.a * s.b;
+    return d;
+}
+
+/*
+ * Clamp a color's channels to the normal range of 0.0 to 1.0.
+ */
+INLINE_MAYBE
+color_t color_clamp(color_t c)
+{
+    c.r = scal_clamp(c.r, S(0.0), S(1.0));
+    c.g = scal_clamp(c.g, S(0.0), S(1.0));
+    c.b = scal_clamp(c.b, S(0.0), S(1.0));
+    c.a = scal_clamp(c.a, S(0.0), S(1.0));
+    return c;
+}
+
+
+/*
+ * Interpolate smoothly between two colors with an alpha value.
+ */
+INLINE_MAYBE
+color_t color_interp(color_t c1, color_t c2, scal_t a)
+{
+    return color_new(c1.r * (S(1.0) - a) + c2.r * a,
+                     c1.g * (S(1.0) - a) + c2.g * a,
+                     c1.b * (S(1.0) - a) + c2.b * a, c1.a);
+}
+
+/*
+ * Interpolate smoothly between three colors with barycentric coordinates.
+ */
+INLINE_MAYBE
+color_t color_interp2(color_t c1, color_t c2, color_t c3, scal_t b[3])
+{
+    return color_new(c1.r * b[0] + c2.r * b[1] + c3.r * b[2],
+                     c1.g * b[0] + c2.g * b[1] + c3.g * b[2],
+                     c1.b * b[0] + c2.b * b[1] + c3.b * b[2], c1.a);
+}
+
+
+/*
+ * Define integer types for a 32-bit RGBA color representation.
+ */
+typedef uint8_t     rgbachan_t;
+typedef uint32_t    rgba_t;
+
 /*
  * Split a color into 8-bit RGBA channels.
  */
-__fast__
+INLINE_MAYBE
 void color_split(color_t c, rgbachan_t* r, rgbachan_t* g, rgbachan_t* b, rgbachan_t* a)
 {
     if (r) *r = (rgbachan_t)(c.r * S(255.0));
@@ -95,17 +204,42 @@ void color_split(color_t c, rgbachan_t* r, rgbachan_t* g, rgbachan_t* b, rgbacha
     if (a) *a = (rgbachan_t)(c.a * S(255.0));
 }
 
+/*
+ * Create a new color from a 32-bit RGBA value.
+ */
+INLINE_MAYBE
+color_t color_from_rgba(rgba_t n)
+{
+    union {
+        rgba_t rgba;
+        struct {
+            rgbachan_t r, g, b, a;
+        } chan;
+    } u;
+    u.rgba = n;
+    colorchan_t r = (colorchan_t)u.chan.r / S(255.0);
+    colorchan_t g = (colorchan_t)u.chan.g / S(255.0);
+    colorchan_t b = (colorchan_t)u.chan.b / S(255.0);
+    colorchan_t a = (colorchan_t)u.chan.a / S(255.0);
+    return color_new(r, g, b, a);
+}
+
 /*
  * Convert a color to a 32-bit RGBA value.
  */
-__fast__
+INLINE_MAYBE
 rgba_t rgba_from_color(color_t c)
 {
-    rgbachan_t r, g, b, a;
-    color_split(c, &r, &g, &b, &a);
-    return ((rgba_t)r << 24) | ((rgba_t)g << 16) | ((rgba_t)b << 8) | (rgba_t)a;
+    union {
+        rgba_t rgba;
+        struct {
+            rgbachan_t r, g, b, a;
+        } chan;
+    } u;
+    color_split(c, &u.chan.r, &u.chan.g, &u.chan.b, &u.chan.a);
+    return u.rgba;
 }
 
 
-#endif // __COLOR_H__
+#endif // _COLOR_H_