PIXEL oily_png_color_interpolate_quick(PIXEL fg, PIXEL bg, int alpha) { BYTE a_com, new_r, new_g, new_b, new_a; if (alpha >= 255) return fg; if (alpha <= 0) return bg; a_com = 255 - alpha; new_r = INT8_MULTIPLY(alpha, R_BYTE(fg)) + INT8_MULTIPLY(a_com, R_BYTE(bg)); new_g = INT8_MULTIPLY(alpha, G_BYTE(fg)) + INT8_MULTIPLY(a_com, G_BYTE(bg)); new_b = INT8_MULTIPLY(alpha, B_BYTE(fg)) + INT8_MULTIPLY(a_com, B_BYTE(bg)); new_a = INT8_MULTIPLY(alpha, A_BYTE(fg)) + INT8_MULTIPLY(a_com, A_BYTE(bg)); return BUILD_PIXEL(new_r, new_g, new_b, new_a); }
PIXEL oily_png_compose_color(PIXEL fg, PIXEL bg) { // Check for simple cases first if ((A_BYTE(fg) == 0xff) || (A_BYTE(bg) == 0x00)) return fg; if (A_BYTE(fg) == 0x00) return bg; // Calculate the new values using fast 8-bit multiplication BYTE a_com = INT8_MULTIPLY(0xff - A_BYTE(fg), A_BYTE(bg)); BYTE new_r = INT8_MULTIPLY(A_BYTE(fg), R_BYTE(fg)) + INT8_MULTIPLY(a_com, R_BYTE(bg)); BYTE new_g = INT8_MULTIPLY(A_BYTE(fg), G_BYTE(fg)) + INT8_MULTIPLY(a_com, G_BYTE(bg)); BYTE new_b = INT8_MULTIPLY(A_BYTE(fg), B_BYTE(fg)) + INT8_MULTIPLY(a_com, B_BYTE(bg)); BYTE new_a = A_BYTE(fg) + a_com; return BUILD_PIXEL(new_r, new_g, new_b, new_a); }
// Assume R == G == B. ChunkyPNG uses the B byte fot performance reasons. // We'll uses the same to remain compatible with ChunkyPNG. void oily_png_encode_scanline_grayscale_8bit(BYTE* bytes, VALUE pixels, long y, long width, VALUE encoding_palette) { UNUSED_PARAMETER(encoding_palette); long x; PIXEL pixel; for (x = 0; x < width; x++) { pixel = NUM2UINT(rb_ary_entry(pixels, y * width + x)); bytes[x] = B_BYTE(pixel); } }
void oily_png_encode_scanline_truecolor_alpha_8bit(BYTE* bytes, VALUE pixels, long y, long width, VALUE encoding_palette) { UNUSED_PARAMETER(encoding_palette); long x; PIXEL pixel; for (x = 0; x < width; x++) { pixel = NUM2UINT(rb_ary_entry(pixels, y * width + x)); bytes[x * 4 + 0] = R_BYTE(pixel); bytes[x * 4 + 1] = G_BYTE(pixel); bytes[x * 4 + 2] = B_BYTE(pixel); bytes[x * 4 + 3] = A_BYTE(pixel); } }
SDL_Color rubysdl2_Color_to_SDL_Color(VALUE rgba) { SDL_Color color; if (rgba == Qnil) { color.r = color.g = color.b = 0; color.a = 255; return color; } else { PIXEL pixel = NUM2UINT(rgba); color.r = R_BYTE(pixel); color.g = G_BYTE(pixel); color.b = B_BYTE(pixel); color.a = A_BYTE(pixel); return color; } }
VALUE Color_s_b(VALUE self, VALUE value) { return INT2FIX(B_BYTE(NUM2UINT(value))); }
VALUE oily_png_color_b(VALUE self, VALUE value) { UNUSED_PARAMETER(self); return INT2FIX(B_BYTE(NUM2UINT(value))); }