X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=padding_effect.cpp;h=48ad54ff3e83264cb6d2016a74e3753336e3074f;hp=f576baa2d5c3f8cb043a0395cdd3d3314a7bdd90;hb=eff011224abc5dc81f801f3ea44572287a55bcac;hpb=8c7e53028a3ef4805d2608643041a5d7e6bd1b6e

diff --git a/padding_effect.cpp b/padding_effect.cpp
index f576baa..48ad54f 100644
--- a/padding_effect.cpp
+++ b/padding_effect.cpp
@@ -14,13 +14,26 @@ PaddingEffect::PaddingEffect()
 	  output_width(1280),
 	  output_height(720),
 	  top(0),
-	  left(0)
+	  left(0),
+	  border_offset_top(0.0f),
+	  border_offset_left(0.0f),
+	  border_offset_bottom(0.0f),
+	  border_offset_right(0.0f)
 {
 	register_vec4("border_color", (float *)&border_color);
 	register_int("width", &output_width);
 	register_int("height", &output_height);
 	register_float("top", &top);
 	register_float("left", &left);
+	register_float("border_offset_top", &border_offset_top);
+	register_float("border_offset_left", &border_offset_left);
+	register_float("border_offset_bottom", &border_offset_bottom);
+	register_float("border_offset_right", &border_offset_right);
+	register_uniform_vec2("offset", uniform_offset);
+	register_uniform_vec2("scale", uniform_scale);
+	register_uniform_vec2("normalized_coords_to_texels", uniform_normalized_coords_to_texels);
+	register_uniform_vec2("offset_bottomleft", uniform_offset_bottomleft);
+	register_uniform_vec2("offset_topright", uniform_offset_topright);
 }
 
 string PaddingEffect::output_fragment_shader()
@@ -32,35 +45,23 @@ void PaddingEffect::set_gl_state(GLuint glsl_program_num, const string &prefix,
 {
 	Effect::set_gl_state(glsl_program_num, prefix, sampler_num);
 
-	float offset[2] = {
-		left / output_width,
-		(output_height - input_height - top) / output_height
-	};
-	set_uniform_vec2(glsl_program_num, prefix, "offset", offset);
-
-	float scale[2] = {
-		float(output_width) / input_width,
-		float(output_height) / input_height
-	};
-	set_uniform_vec2(glsl_program_num, prefix, "scale", scale);
-
-	// Due to roundoff errors, the test against 0.5 is seldom exact,
-	// even though we test for less than and not less-than-or-equal.
-	// We'd rather keep an extra border pixel in those very rare cases
-	// (where the image is shifted pretty much exactly a half-pixel)
-	// than losing a pixel in the common cases of integer shift.
-	// Thus the 1e-3 fudge factors.
-	float texcoord_min[2] = {
-		float((0.5f - 1e-3) / input_width),
-		float((0.5f - 1e-3) / input_height)
-	};
-	set_uniform_vec2(glsl_program_num, prefix, "texcoord_min", texcoord_min);
-
-	float texcoord_max[2] = {
-		float(1.0f - (0.5f - 1e-3) / input_width),
-		float(1.0f - (0.5f - 1e-3) / input_height)
-	};
-	set_uniform_vec2(glsl_program_num, prefix, "texcoord_max", texcoord_max);
+	uniform_offset[0] = left / output_width;
+	uniform_offset[1] = (output_height - input_height - top) / output_height;
+
+	uniform_scale[0] = float(output_width) / input_width;
+	uniform_scale[1] = float(output_height) / input_height;
+
+	uniform_normalized_coords_to_texels[0] = float(input_width);
+	uniform_normalized_coords_to_texels[1] = float(input_height);
+
+	// Texels -0.5..0.5 should map to light level 0..1 (and then we
+	// clamp the rest).
+	uniform_offset_bottomleft[0] = 0.5f - border_offset_left;
+	uniform_offset_bottomleft[1] = 0.5f + border_offset_bottom;
+
+	// Texels size-0.5..size+0.5 should map to light level 1..0 (and then clamp).
+	uniform_offset_topright[0] = input_width + 0.5f + border_offset_right;
+	uniform_offset_topright[1] = input_height + 0.5f - border_offset_top;
 }
 	
 // We don't change the pixels of the image itself, so the only thing that 
@@ -100,23 +101,16 @@ bool PaddingEffect::needs_srgb_primaries() const
 
 Effect::AlphaHandling PaddingEffect::alpha_handling() const
 {
-	// If the border color is black, it doesn't matter if we're pre- or postmultiplied.
-	// Note that for non-solid black (i.e. alpha < 1.0), we're equally fine with
-	// pre- and postmultiplied, but later effects might change this status
-	// (consider e.g. blur), so setting DONT_CARE_ALPHA_TYPE is inappropriate,
-	// as it propagate blank alpha through this effect.
-	if (border_color.r == 0.0 && border_color.g == 0.0 && border_color.b == 0.0 && border_color.a == 1.0) {
-		return DONT_CARE_ALPHA_TYPE;
-	}
-
-	// If the border color is solid, we preserve blank alpha, as we never output any
-	// new non-solid pixels.
+	// If the border color is solid, it doesn't matter if we're pre- or postmultiplied.
 	if (border_color.a == 1.0) {
-		return INPUT_PREMULTIPLIED_ALPHA_KEEP_BLANK;
+		return DONT_CARE_ALPHA_TYPE;
 	}
 
 	// Otherwise, we're going to output our border color in premultiplied alpha,
 	// so the other pixels better be premultiplied as well.
+	// Note that for non-solid black (i.e. alpha < 1.0), we're equally fine with
+	// pre- and postmultiplied, but we are _not_ fine with blank being passed through,
+	// and we don't have a way to specify that.
 	return INPUT_AND_OUTPUT_PREMULTIPLIED_ALPHA;
 }
 	
@@ -133,4 +127,25 @@ void PaddingEffect::inform_input_size(unsigned input_num, unsigned width, unsign
 	input_height = height;
 }
 
+IntegralPaddingEffect::IntegralPaddingEffect() {}
+
+bool IntegralPaddingEffect::set_int(const std::string &key, int value)
+{
+	if (key == "top" || key == "left") {
+		return PaddingEffect::set_float(key, value);
+	} else {
+		return PaddingEffect::set_int(key, value);
+	}
+}
+
+bool IntegralPaddingEffect::set_float(const std::string &key, float value)
+{
+	if (key == "top" || key == "left") {
+		// These are removed as float parameters from this version.
+		return false;
+	} else {
+		return PaddingEffect::set_float(key, value);
+	}
+}
+
 }  // namespace movit