3 files changed, 9 insertions, 4 deletions
diff --git a/src/backend/gl/gl_common.c b/src/backend/gl/gl_common.c
index a7d2aab..a9ded56 100644
--- a/src/backend/gl/gl_common.c
+++ b/src/backend/gl/gl_common.c
@@ -382,8 +382,9 @@ static void _gl_compose(backend_t *base, struct backend_image *img, GLuint targe
 	if (win_shader->uniform_invert_color >= 0) {
 		glUniform1i(win_shader->uniform_invert_color, img->color_inverted);
 	}
-	if (win_shader->uniform_tex >= 0) {
-		glUniform1i(win_shader->uniform_tex, 0);
+	if (win_shader->uniform_effective_size >= 0) {
+		glUniform2f(win_shader->uniform_effective_size, (float)img->ewidth,
+		            (float)img->eheight);
 	}
 	if (win_shader->uniform_dim >= 0) {
 		glUniform1f(win_shader->uniform_dim, (float)img->dim);
@@ -596,6 +597,7 @@ static bool gl_win_shader_from_stringv(const char **vshader_strv,
 	bind_uniform(ret, opacity);
 	bind_uniform(ret, invert_color);
 	bind_uniform(ret, tex);
+	bind_uniform(ret, effective_size);
 	bind_uniform(ret, dim);
 	bind_uniform(ret, brightness);
 	bind_uniform(ret, max_brightness);
diff --git a/src/backend/gl/gl_common.h b/src/backend/gl/gl_common.h
index 3a78865..f4eee29 100644
--- a/src/backend/gl/gl_common.h
+++ b/src/backend/gl/gl_common.h
@@ -35,6 +35,7 @@ typedef struct {
 	GLint uniform_opacity;
 	GLint uniform_invert_color;
 	GLint uniform_tex;
+	GLint uniform_effective_size;
 	GLint uniform_dim;
 	GLint uniform_brightness;
 	GLint uniform_max_brightness;
diff --git a/src/backend/gl/shaders.c b/src/backend/gl/shaders.c
index 4a18e62..7cee752 100644
--- a/src/backend/gl/shaders.c
+++ b/src/backend/gl/shaders.c
@@ -88,6 +88,7 @@ const char win_shader_glsl[] = GLSL(330,
 	uniform bool invert_color;
 	in vec2 texcoord;
 	uniform sampler2D tex;
+	uniform vec2 effective_size;
 	uniform sampler2D brightness;
 	uniform float max_brightness;
 	// Signed distance field for rectangle center at (0, 0), with size of
@@ -121,7 +122,7 @@ const char win_shader_glsl[] = GLSL(330,
 		// Using mix() to avoid a branch here.
 		vec4 rim_color = mix(c, border_color, clamp(border_width, 0.0f, 1.0f));
 
-		vec2 outer_size = vec2(textureSize(tex, 0));
+		vec2 outer_size = effective_size;
 		vec2 inner_size = outer_size - vec2(corner_radius) * 2.0f;
 		float rect_distance = rectangle_sdf(texcoord - outer_size / 2.0f,
 		    inner_size / 2.0f) - corner_radius;
@@ -148,7 +149,8 @@ const char win_shader_default[] = GLSL(330,
 	uniform sampler2D tex;
 	vec4 default_post_processing(vec4 c);
 	vec4 window_shader() {
-		vec4 c = texelFetch(tex, ivec2(texcoord), 0);
+		vec2 texsize = textureSize(tex, 0);
+		vec4 c = texture2D(tex, texcoord / texsize, 0);
 		return default_post_processing(c);
 	}
 );