From 11a58b5adf012ccc608da717ccba54d3f49d7430 Mon Sep 17 00:00:00 2001
From: brunoherbelin <bruno.herbelin@gmail.com>
Date: Thu, 12 Nov 2020 22:07:00 +0100
Subject: [PATCH] Adding UV texture coordinates to Surface and ImageShader.

---
 ImageShader.cpp      | 13 +++++++++----
 ImageShader.h        |  2 +-
 Primitives.cpp       | 11 +++++++++++
 Primitives.h         |  3 +++
 rsc/shaders/image.fs |  6 +++++-
 5 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/ImageShader.cpp b/ImageShader.cpp
index bfa7c0e..45b32c4 100644
--- a/ImageShader.cpp
+++ b/ImageShader.cpp
@@ -10,7 +10,7 @@ static ShadingProgram imageShadingProgram("shaders/image.vs", "shaders/image.fs"
 const char* ImageShader::mask_names[11] = { "None", "Glow", "Halo", "Circle", "Round", "Vignette", "Top", "Botton", "Left", "Right", "Custom" };
 std::vector< uint > ImageShader::mask_presets;
 
-ImageShader::ImageShader(): Shader(), custom_textureindex(0)
+ImageShader::ImageShader(): Shader(), mask(0), custom_textureindex(0), stipple(0.0), uv(0.0, 0.0, 1.0, 1.0)
 {
     // first initialization
     if ( mask_presets.empty() ) {
@@ -36,19 +36,20 @@ void ImageShader::use()
     Shader::use();
 
     program_->setUniform("stipple", stipple);
+    program_->setUniform("uv", uv);
 
     glActiveTexture(GL_TEXTURE1);
     if ( mask < 10 ) {
         glBindTexture(GL_TEXTURE_2D, mask_presets[mask]);
-
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     }
     else
         glBindTexture(GL_TEXTURE_2D, custom_textureindex);
+
     glActiveTexture(GL_TEXTURE0);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,  GL_MIRRORED_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,  GL_MIRRORED_REPEAT);
 
 }
 
@@ -61,6 +62,9 @@ void ImageShader::reset()
     custom_textureindex = mask_presets[0];
     // no stippling
     stipple = 0.f;
+    // normal uv
+    uv = glm::vec4(0.0, 0.0, 1.0, 1.0);
+//    uv = glm::vec4(0.0, 0.0, 2.0, 2.0);
 }
 
 void ImageShader::operator = (const ImageShader &S )
@@ -70,6 +74,7 @@ void ImageShader::operator = (const ImageShader &S )
     mask = S.mask;
     custom_textureindex = S.custom_textureindex;
     stipple = S.stipple;
+    uv = S.uv;
 }
 
 
diff --git a/ImageShader.h b/ImageShader.h
index 8affcf0..9c4ba14 100644
--- a/ImageShader.h
+++ b/ImageShader.h
@@ -16,7 +16,6 @@ class ImageShader : public Shader
 public:
 
     ImageShader();
-//    virtual ~ImageShader() {}
 
     void use() override;
     void reset() override;
@@ -27,6 +26,7 @@ public:
     uint mask;
     uint custom_textureindex;
     float stipple;
+    glm::vec4 uv;
 
     static const char* mask_names[11];
     static std::vector< uint > mask_presets;
diff --git a/Primitives.cpp b/Primitives.cpp
index 25d12e1..4510d15 100644
--- a/Primitives.cpp
+++ b/Primitives.cpp
@@ -95,6 +95,17 @@ void Surface::draw(glm::mat4 modelview, glm::mat4 projection)
     glBindTexture(GL_TEXTURE_2D, 0);
 }
 
+void Surface::setTextureUV(glm::vec4 uv)
+{
+    dynamic_cast<ImageShader*>(shader_)->uv = uv;
+}
+
+glm::vec4 Surface::textureUV() const
+{
+    return dynamic_cast<ImageShader*>(shader_)->uv;
+}
+
+
 ImageSurface::ImageSurface(const std::string& path, Shader *s) : Surface(s), resource_(path)
 {
 
diff --git a/Primitives.h b/Primitives.h
index e7f19e2..958f70e 100644
--- a/Primitives.h
+++ b/Primitives.h
@@ -27,6 +27,9 @@ public:
     void draw (glm::mat4 modelview, glm::mat4 projection) override;
     void accept (Visitor& v) override;
 
+    void setTextureUV(glm::vec4 uv);
+    glm::vec4 textureUV() const;
+
     inline void setTextureIndex(uint t) { textureindex_ = t; }
     inline uint textureIndex() const { return textureindex_; }
 
diff --git a/rsc/shaders/image.fs b/rsc/shaders/image.fs
index 3e2e2ff..4d123bd 100644
--- a/rsc/shaders/image.fs
+++ b/rsc/shaders/image.fs
@@ -11,11 +11,15 @@ uniform vec3      iResolution;           // viewport resolution (in pixels)
 
 uniform vec4 color;
 uniform float stipple;
+uniform vec4 uv;
 
 void main()
 {
+    // adjust UV
+    vec2 texcoord = vec2(uv.x, uv.y) + vertexUV * vec2(uv.z - uv.x, uv.w - uv.y);
+
     // color is a mix of texture (manipulated with brightness & contrast), vertex and uniform colors
-    vec4 textureColor = texture(iChannel0, vertexUV);
+    vec4 textureColor = texture(iChannel0, texcoord);
     vec3 RGB = textureColor.rgb * vertexColor.rgb * color.rgb;
 
     // alpha is a mix of texture alpha, vertex alpha, and uniform alpha affected by stippling