working draft

diff --git a/Cargo.toml b/Cargo.toml
index 97473f8..69c1c82 100644 (file)
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,3 +12,6 @@ version = "0.10.0"
 [dependencies.sdl2]
 version = "0.32.2"
 features = ["bundled", "static-link"]
+
+[dependencies.image]
+version = "0.22.2"

diff --git a/src/main.rs b/src/main.rs
index 6718096..e88a368 100644 (file)
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,18 +1,13 @@
 extern crate sdl2;
 extern crate gl;
+extern crate image;
 
 use sdl2::video::GLProfile;
 use gl::types::*;
-
-use std;
-
-/*enum Vattr {
-       VATTR_VERTEX,
-       VATTR_TEXCOORD
-}*/
+use image::GenericImageView;
 
 static WIN_W : u32 = 800;
-static WIN_H : u32 = 600;
+static WIN_H : u32 = 800;
 
 static VERTEX_DATA : [GLfloat; 12] = [
        -0.5, -0.5,
@@ -24,23 +19,37 @@ static VERTEX_DATA : [GLfloat; 12] = [
        -0.5, 0.5
 ];
 
+static TEX_DATA : [GLfloat; 12] = [
+    0.0, 1.0,
+    1.0, 1.0,
+    1.0, 0.0,
+
+    0.0, 1.0,
+    1.0, 0.0,
+    0.0, 0.0
+];
+
 static NUM_VERTICES : GLint = 6;
 static VERTEX_LOC : u32 = 0;
-
-let tex : u32 = 0;
+static TEX_LOC : u32 = 1;
 
 static VS : &'static str =
 "#version 130\n\
- attribute vec4 pos;\n\
+ in vec4 pos;\n\
+ in vec2 in_tex_coord;\n\
+ out vec2 tex_coord;\n\
  void main() {\n\
     gl_Position = pos;\n\
+    tex_coord = in_tex_coord;\n\
  }";
 
 static FS : &'static str =
 "#version 130\n\
+ uniform sampler2D tex;\n\
+ in vec2 tex_coord;\n\
  out vec4 color;\n\
  void main() {\n\
-    color = vec4(0.0, 0.5, 0.8, 1.0);\n\
+    color = texture2D(tex, tex_coord);\n\
  }";
 
 fn compile_sdr(src: &str, stage:GLenum) -> GLuint {
@@ -99,7 +108,27 @@ fn link_sdr_prog(vs: GLuint, fs: GLuint) -> GLuint {
     }
 }
 
+fn gen_tex(fname : String, _id : &mut GLuint) {
+    let img : image::DynamicImage = image::open(&std::path::Path::new(&fname)).ok().expect("Can't open image.\n");
+    let (_w, _h) = img.dimensions();
+
+    unsafe {
+        gl::GenTextures(1, _id);
+        gl::BindTexture(gl::TEXTURE_2D, *_id);
+        gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_S, gl::REPEAT as i32);
+        gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_T, gl::REPEAT as i32);
+        gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR as i32);
+        gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::LINEAR as i32);
+        gl::TexImage2D(gl::TEXTURE_2D, 0, gl::RGBA as i32,
+                       _w as i32, _h as i32, 0,
+                       gl::RGBA, gl::UNSIGNED_BYTE,
+                       img.to_rgba().into_raw().as_ptr() as *const std::ffi::c_void);
+        gl::BindTexture(gl::TEXTURE_2D, 0);
+    }
+}
+
 fn main() {
+    //TODO FIXME init
     let sdl_ctx = sdl2::init().unwrap();
     let vid_sys = sdl_ctx.video().unwrap();
     let gl_attr = vid_sys.gl_attr();
@@ -117,33 +146,47 @@ fn main() {
     let _gl = gl::load_with(|s| vid_sys.gl_get_proc_address(s) as
                             *const std::os::raw::c_void);
 
-    let mut vao = 0;
-    let mut vbo = 0;
+    let mut vao = 1;
+    let mut vbo_pos = 1;
+    let mut vbo_tex = 2;
+    let sprog;
 
-    let mut sprog;
     let fs;
     let vs;
 
+    let mut tex_igalia : GLuint = 1;
+    let mut tex_guadec : GLuint = 2;
+    let mut tex_sel = tex_igalia;
+
+    let mut uloc_stex : GLint = -1;
+
+    gen_tex("data/igalia.png".to_string(), &mut tex_igalia);
+    gen_tex("data/guadec.png".to_string(), &mut tex_guadec);
+
     unsafe {
-        gl::ClearColor(0.3, 0.1, 0.1, 1.0);
+        gl::ClearColor(0.0, 0.0, 0.0, 1.0);
+        gl::Enable(gl::BLEND);
+        gl::BlendFunc(gl::SRC_ALPHA, gl::ONE_MINUS_SRC_ALPHA);
         gl::GenVertexArrays(1, &mut vao);
         gl::BindVertexArray(vao);
 
-        gl::GenBuffers(1, &mut vbo);
-        gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
+        gl::GenBuffers(1, &mut vbo_pos);
+        gl::BindBuffer(gl::ARRAY_BUFFER, vbo_pos);
         gl::BufferData(gl::ARRAY_BUFFER, (VERTEX_DATA.len() * std::mem::size_of::<GLfloat>()) as GLsizeiptr,
                        std::mem::transmute(&VERTEX_DATA[0]),
                        gl::STATIC_DRAW);
         gl::BindBuffer(gl::ARRAY_BUFFER, 0);
+        gl::GenBuffers(1, &mut vbo_tex);
+        gl::BindBuffer(gl::ARRAY_BUFFER, vbo_tex);
+        gl::BufferData(gl::ARRAY_BUFFER, (TEX_DATA.len() * std::mem::size_of::<GLfloat>()) as GLsizeiptr,
+                       std::mem::transmute(&TEX_DATA[0]),
+                       gl::STATIC_DRAW);
+        gl::BindBuffer(gl::ARRAY_BUFFER, 0);
 
         vs = compile_sdr(VS, gl::VERTEX_SHADER);
         fs = compile_sdr(FS, gl::FRAGMENT_SHADER);
 
         sprog = link_sdr_prog(vs, fs);
-        let att_str = std::ffi::CString::new("position").unwrap();
-
-        gl::BindAttribLocation(sprog, VERTEX_LOC, att_str.as_ptr());
-        sprog = link_sdr_prog(vs, fs);
 
         gl::UseProgram(sprog);
     }
@@ -157,31 +200,59 @@ fn main() {
                 sdl2::event::Event::KeyDown {keycode:
                     Some(sdl2::keyboard::Keycode::Escape), ..} =>
                         break 'main,
+                sdl2::event::Event::KeyDown {keycode:
+                    Some(sdl2::keyboard::Keycode::I), ..} =>
+                        tex_sel = tex_igalia,
+                sdl2::event::Event::KeyDown {keycode:
+                    Some(sdl2::keyboard::Keycode::G), ..} =>
+                        tex_sel = tex_guadec,
                 _ => {},
             }
         }
 
+        //TODO FIXME: display
         unsafe {
+            let uni_str = std::ffi::CString::new("tex").unwrap();
+            uloc_stex = gl::GetUniformLocation(sprog, uni_str.as_ptr());
+            if uloc_stex > -1 {
+                gl::Uniform1i(uloc_stex, tex_sel as i32);
+            }
+
             gl::Clear(gl::COLOR_BUFFER_BIT);
             gl::Viewport(0, 0, WIN_W as i32, WIN_H as i32);
 
+            /* pos */
             gl::EnableVertexAttribArray(VERTEX_LOC);
-            gl::BindBuffer(gl::ARRAY_BUFFER, vbo);
+            gl::BindBuffer(gl::ARRAY_BUFFER, vbo_pos);
             gl::VertexAttribPointer(VERTEX_LOC, 2,
                                     gl::FLOAT, gl::FALSE,
                                     0 as i32, std::ptr::null());
 
+            /* tex coords */
+            gl::EnableVertexAttribArray(TEX_LOC);
+            gl::BindBuffer(gl::ARRAY_BUFFER, vbo_tex);
+            gl::VertexAttribPointer(TEX_LOC, 2,
+                    gl::FLOAT, gl::FALSE,
+                    0 as i32, std::ptr::null());
+
+            gl::ActiveTexture(gl::TEXTURE0 + tex_sel);
+            gl::BindTexture(gl::TEXTURE_2D, tex_sel);
+
             gl::DrawArrays(gl::TRIANGLES, 0, NUM_VERTICES);
         }
 
         win.gl_swap_window();
     }
 
+    //TODO FIXME: cleanup
     unsafe {
         gl::DeleteProgram(sprog);
         gl::DeleteShader(vs);
         gl::DeleteShader(fs);
-        gl::DeleteBuffers(1, &vbo);
+        gl::DeleteBuffers(1, &vbo_pos);
+        gl::DeleteBuffers(1, &vbo_tex);
         gl::DeleteVertexArrays(1, &vao);
+        gl::DeleteTextures(1, &tex_igalia);
+        gl::DeleteTextures(1, &tex_guadec);
     }
 }