X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=dither_effect.cpp;h=4643d07180993fdd286e460eba758b08d949d9d3;hp=87e729a3c9feca0a7253e7617eeb41d287d9f68b;hb=1514db1d0f3963dbc18177d2fd7eaae16a069c3b;hpb=f1a81dca72da9aa5103527b8c9494381204e70c5

diff --git a/dither_effect.cpp b/dither_effect.cpp
index 87e729a..4643d07 100644
--- a/dither_effect.cpp
+++ b/dither_effect.cpp
@@ -1,9 +1,11 @@
-#include <math.h>
+#include <GL/glew.h>
 #include <assert.h>
+#include <algorithm>
 
 #include "dither_effect.h"
+#include "effect_util.h"
+#include "init.h"
 #include "util.h"
-#include "opengl.h"
 
 namespace {
 
@@ -39,7 +41,9 @@ DitherEffect::~DitherEffect()
 
 std::string DitherEffect::output_fragment_shader()
 {
-	return read_file("dither_effect.frag");
+	char buf[256];
+	sprintf(buf, "#define NEED_EXPLICIT_ROUND %d\n", (movit_num_wrongly_rounded > 0));
+	return buf + read_file("dither_effect.frag");
 }
 
 void DitherEffect::update_texture(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num)
@@ -85,6 +89,10 @@ void DitherEffect::set_gl_state(GLuint glsl_program_num, const std::string &pref
 {
 	Effect::set_gl_state(glsl_program_num, prefix, sampler_num);
 
+	assert(width > 0);
+	assert(height > 0);
+	assert(num_bits > 0);
+
 	if (width != last_width || height != last_height || num_bits != last_num_bits) {
 		update_texture(glsl_program_num, prefix, sampler_num);
 		last_width = width;
@@ -105,4 +113,9 @@ void DitherEffect::set_gl_state(GLuint glsl_program_num, const std::string &pref
 	// we don't have to worry about it.	
 	float tc_scale[] = { float(width) / float(texture_width), float(height) / float(texture_height) };
 	set_uniform_vec2(glsl_program_num, prefix, "tc_scale", tc_scale);
+
+	// Used if the shader needs to do explicit rounding.
+	int round_fac = (1 << num_bits) - 1;
+	set_uniform_float(glsl_program_num, prefix, "round_fac", round_fac);
+	set_uniform_float(glsl_program_num, prefix, "inv_round_fac", 1.0f / round_fac);
 }