diff --git a/odin/sdl-opengl-rendering/src/frag.glsl b/odin/sdl-opengl-rendering/src/frag.glsl
index e5daf9f..58ae6e0 100644
--- a/odin/sdl-opengl-rendering/src/frag.glsl
+++ b/odin/sdl-opengl-rendering/src/frag.glsl
@@ -1,7 +1,9 @@
-#version 140
+#version 330
-out vec4 LFragment;
+out vec4 FragColor;
+
+in vec4 vertexColor;
void main() {
- LFragment = vec4( 1.0, 1.0, 1.0, 1.0 );
+ FragColor = vertexColor;
}
diff --git a/odin/sdl-opengl-rendering/src/main.odin b/odin/sdl-opengl-rendering/src/main.odin
index 07c249d..3b4a6f6 100644
--- a/odin/sdl-opengl-rendering/src/main.odin
+++ b/odin/sdl-opengl-rendering/src/main.odin
@@ -9,22 +9,27 @@ State :: struct {
window: ^sdl3.Window,
program: u32,
vertex_pos_location: u32,
+ vao: u32,
vbo: u32,
ibo: u32,
+ wireframe: bool,
}
init :: proc() -> (state: State, ok: bool) {
GL_MAJOR :: 3
- GL_MINOR :: 1
+ GL_MINOR :: 3
sdl3.Init(sdl3.InitFlags{.VIDEO}) or_return
sdl3.GL_SetAttribute(.CONTEXT_MAJOR_VERSION, GL_MAJOR) or_return
sdl3.GL_SetAttribute(.CONTEXT_MINOR_VERSION, GL_MINOR) or_return
sdl3.GL_SetAttribute(.CONTEXT_PROFILE_MASK, c.int(sdl3.GL_CONTEXT_PROFILE_CORE)) or_return
+ sdl3.GL_SetSwapInterval(1) // vsync
state.window = sdl3.CreateWindow("SDL visual experiment", 640, 480, {.FULLSCREEN, .OPENGL})
(state.window != nil) or_return
+ sdl3.StartTextInput(state.window) or_return
+
gl_ctx := sdl3.GL_CreateContext(state.window)
(gl_ctx != nil) or_return
@@ -36,35 +41,48 @@ init :: proc() -> (state: State, ok: bool) {
) or_return
// log.debug("Doing Opengl stuff")
- vertex_pos_location := OpenGL.GetAttribLocation(state.program, "LVertexPos2D")
+ vertex_pos_location := OpenGL.GetAttribLocation(state.program, "aPos")
(vertex_pos_location != -1) or_return
state.vertex_pos_location = u32(vertex_pos_location)
OpenGL.ClearColor(0, 0, 0, 1)
// VBO data
- vertex_data := [?]f32{-0.5, -0.5, 0.5, -0.5, 0.5, 0.5, -0.5, 0.5}
- vbos: [1]u32
+ vertex_data := 2 * [?]f32{-0.5, -0.5, 0.5, -0.5, 0.5, 0.5, -0.5, 0.5}
// IBO data
index_data := [?]u32{0, 1, 2, 3}
- ibos: [1]u32
+
+
+ OpenGL.GenVertexArrays(1, &state.vao)
+ OpenGL.BindVertexArray(state.vao)
//Create VBO
- OpenGL.GenBuffers(1, auto_cast &vbos)
- OpenGL.BindBuffer(OpenGL.ARRAY_BUFFER, vbos[0])
+ OpenGL.GenBuffers(1, &state.vbo)
+ OpenGL.BindBuffer(OpenGL.ARRAY_BUFFER, state.vbo)
OpenGL.BufferData(OpenGL.ARRAY_BUFFER, 2 * 4 * size_of(f32), &vertex_data, OpenGL.STATIC_DRAW)
- state.vbo = vbos[0]
- OpenGL.GenBuffers(1, auto_cast &ibos)
- OpenGL.BindBuffer(OpenGL.ELEMENT_ARRAY_BUFFER, ibos[0])
+ OpenGL.EnableVertexAttribArray(state.vertex_pos_location)
+ OpenGL.VertexAttribPointer(
+ state.vertex_pos_location,
+ 2,
+ OpenGL.FLOAT,
+ false,
+ 2 * size_of(f32),
+ 0,
+ )
+
+ OpenGL.GenBuffers(1, auto_cast &state.ibo)
+ OpenGL.BindBuffer(OpenGL.ELEMENT_ARRAY_BUFFER, state.ibo)
OpenGL.BufferData(
OpenGL.ELEMENT_ARRAY_BUFFER,
4 * size_of(u32),
&index_data,
OpenGL.STATIC_DRAW,
)
- state.ibo = ibos[0]
+
+ OpenGL.BindVertexArray(0)
+ OpenGL.DisableVertexAttribArray(state.vertex_pos_location)
return state, true
}
@@ -75,25 +93,19 @@ render :: proc(state: State) {
OpenGL.UseProgram(state.program)
defer OpenGL.UseProgram(0)
- OpenGL.EnableVertexAttribArray(state.vertex_pos_location)
- defer OpenGL.DisableVertexAttribArray(state.vertex_pos_location)
+ if state.wireframe {
+ OpenGL.PolygonMode(OpenGL.FRONT_AND_BACK, OpenGL.LINE)
+ } else {
+ OpenGL.PolygonMode(OpenGL.FRONT_AND_BACK, OpenGL.FILL)
+ }
- OpenGL.BindBuffer(OpenGL.ARRAY_BUFFER, state.vbo)
- OpenGL.VertexAttribPointer(
- state.vertex_pos_location,
- 2,
- OpenGL.FLOAT,
- false,
- 2 * size_of(f32),
- 0,
- )
-
- OpenGL.BindBuffer(OpenGL.ELEMENT_ARRAY_BUFFER, state.ibo)
+ OpenGL.BindVertexArray(state.vao)
OpenGL.DrawElements(OpenGL.TRIANGLE_FAN, 4, OpenGL.UNSIGNED_INT, nil)
}
close :: proc(state: State) {
OpenGL.DeleteProgram(state.program)
+ _ = sdl3.StopTextInput(state.window)
sdl3.DestroyWindow(state.window)
sdl3.Quit()
}
@@ -105,23 +117,25 @@ main :: proc() {
defer close(state)
quit := false
- log.debug("Created context")
for !quit {
- sdl3.StartTextInput(state.window) or_break
event: sdl3.Event
for sdl3.PollEvent(&event) {
#partial switch event.type {
+ case .WINDOW_RESIZED:
+ OpenGL.Viewport(0, 0, event.window.data1, event.window.data2)
case .QUIT:
quit = true
+ case .TEXT_INPUT:
+ switch ([^]u8)(event.text.text)[0] {
+ case 'w':
+ state.wireframe = !state.wireframe
+ }
+ log.debug(event.text)
}
}
render(state)
sdl3.GL_SwapWindow(state.window)
- sdl3.StopTextInput(state.window) or_break
}
}
-// //Handle keypress
-// else if( e.type == SDL_EVENT_TEXT_INPUT )
-// handleKeys( e.text.text[ 0 ] );
diff --git a/odin/sdl-opengl-rendering/src/vert.glsl b/odin/sdl-opengl-rendering/src/vert.glsl
index a419f7c..3273106 100644
--- a/odin/sdl-opengl-rendering/src/vert.glsl
+++ b/odin/sdl-opengl-rendering/src/vert.glsl
@@ -1,7 +1,10 @@
-#version 140
+#version 330
-in vec2 LVertexPos2D;
+in vec2 aPos;
+
+out vec4 vertexColor;
void main() {
- gl_Position = vec4(LVertexPos2D.x, LVertexPos2D.y, 0, 1 );
+ gl_Position = vec4(aPos.x, aPos.y, 0, 1);
+ vertexColor = vec4((aPos.x + 1) / 2, (aPos.y + 1) / 2, 1, 1);
}