X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=fft_pass_effect.cpp;h=4069be93f636d72a7682cb4971a2d9822afc4f98;hp=c2b47f047c0747459b92682895be7b9a147f5de2;hb=0cdd6e9e30a807056699ed9b3fa023a23ce83af9;hpb=c2371eea5dadf97add7c1a71b8ea660973c9c6de

diff --git a/fft_pass_effect.cpp b/fft_pass_effect.cpp
index c2b47f0..4069be9 100644
--- a/fft_pass_effect.cpp
+++ b/fft_pass_effect.cpp
@@ -1,6 +1,7 @@
 #include <GL/glew.h>
 #include <math.h>
 
+#include "effect_chain.h"
 #include "effect_util.h"
 #include "fp16.h"
 #include "fft_pass_effect.h"
@@ -40,15 +41,13 @@ void FFTPassEffect::set_gl_state(GLuint glsl_program_num, const string &prefix,
 
 	int input_size = (direction == VERTICAL) ? input_height : input_width;
 
-	// See the comments on changes_output_size() in the .h file to see
-	// why this is legal. It is _needed_ because it counteracts the
-	// precision issues we get because we sample the input texture with
-	// normalized coordinates (especially when the repeat count along
-	// the axis is not a power of two); we very rapidly end up in narrowly
-	// missing a texel center, which causes precision loss to propagate
-	// throughout the FFT.
-	assert(*sampler_num == 1);
-	glActiveTexture(GL_TEXTURE0);
+	// This is needed because it counteracts the precision issues we get
+	// because we sample the input texture with normalized coordinates
+	// (especially when the repeat count along the axis is not a power of
+	// two); we very rapidly end up in narrowly missing a texel center,
+	// which causes precision loss to propagate throughout the FFT.
+	Node *self = chain->find_node_for_effect(this);
+	glActiveTexture(chain->get_input_sampler(self, 0));
 	check_error();
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 	check_error();
@@ -118,15 +117,17 @@ void FFTPassEffect::set_gl_state(GLuint glsl_program_num, const string &prefix,
 		// is that we can have multiple FFTs along the same line,
 		// and want to reuse the support texture by repeating it.
 		int base = k * stride * 2 + offset;
-		int support_texture_index;
+		int support_texture_index = i;
+		int src1 = base;
+		int src2 = base + stride;
 		if (direction == FFTPassEffect::VERTICAL) {
 			// Compensate for OpenGL's bottom-left convention.
-			support_texture_index = fft_size - i - 1;
-		} else {
-			support_texture_index = i;
+			support_texture_index = fft_size - support_texture_index - 1;
+			src1 = fft_size - src1 - 1;
+			src2 = fft_size - src2 - 1;
 		}
-		tmp[support_texture_index * 4 + 0] = fp64_to_fp16((base - support_texture_index) / double(input_size));
-		tmp[support_texture_index * 4 + 1] = fp64_to_fp16((base + stride - support_texture_index) / double(input_size));
+		tmp[support_texture_index * 4 + 0] = fp64_to_fp16((src1 - support_texture_index) / double(input_size));
+		tmp[support_texture_index * 4 + 1] = fp64_to_fp16((src2 - support_texture_index) / double(input_size));
 		tmp[support_texture_index * 4 + 2] = fp64_to_fp16(twiddle_real);
 		tmp[support_texture_index * 4 + 3] = fp64_to_fp16(twiddle_imag);
 	}