Removed GLEW dependency (using GLAD instead), axes now use shader, should now work better

src/COMMON.h

@@ -1,7 +1,7 @@
 #pragma once
 
 #include <SDL3/SDL.h>
-#include <GL/glew.h>
+#include <glad/glad.h>
 #include <GL/gl.h>
 #include <glm/glm/glm.hpp>
 #include <glm/glm/gtc/type_ptr.hpp>

src/PACKED.h

@@ -217,6 +217,7 @@ enum ShaderType
 {
     SHADER_LINE,
     SHADER_TEXTURE,
+    SHADER_AXIS,
     SHADER_GRID,
     SHADER_COUNT
 };
@@ -234,6 +235,33 @@ void main()
 }
 )";
 
+const std::string SHADER_AXIS_VERTEX = R"(
+#version 330 core
+layout (location = 0) in vec2 i_position; // full screen line segment: -1..1
+uniform vec2 u_origin_ndc; // world origin in NDC
+uniform int u_axis;       // 0 = X axis, 1 = Y axis
+
+void main()
+{
+    vec2 pos = (u_axis == 0) 
+        ? vec2(i_position.x, u_origin_ndc.y) // horizontal line across screen
+        : vec2(u_origin_ndc.x, i_position.x); // vertical line across screen;
+
+    gl_Position = vec4(pos, 0.0, 1.0);
+}
+)";
+
+const std::string SHADER_GRID_VERTEX = R"(
+#version 330 core
+layout ( location = 0 ) in vec2 i_position;
+out vec2 clip;
+
+void main() {
+    clip = i_position;
+    gl_Position = vec4(i_position, 0.0, 1.0);
+}
+)";
+
 const std::string SHADER_FRAGMENT = R"(
 #version 330 core
 out vec4 o_fragColor;
@@ -260,17 +288,6 @@ void main()
 }
 )";
 
-const std::string SHADER_GRID_VERTEX = R"(
-#version 330 core
-layout ( location = 0 ) in vec2 i_position;
-out vec2 clip;
-
-void main() {
-    clip = i_position;
-    gl_Position = vec4(i_position, 0.0, 1.0);
-}
-)";
-
 const std::string SHADER_GRID_FRAGMENT = R"(
 #version 330 core
 in vec2 clip;
@@ -301,11 +318,13 @@ void main()
 }
 )";
 
+#define SHADER_UNIFORM_AXIS "u_axis"
 #define SHADER_UNIFORM_COLOR "u_color"
 #define SHADER_UNIFORM_TRANSFORM "u_transform"
 #define SHADER_UNIFORM_TINT "u_tint"
 #define SHADER_UNIFORM_COLOR_OFFSET "u_color_offset"
 #define SHADER_UNIFORM_OFFSET "u_offset"
+#define SHADER_UNIFORM_ORIGIN_NDC "u_origin_ndc"
 #define SHADER_UNIFORM_SIZE "u_size"
 #define SHADER_UNIFORM_MODEL "u_model"
 #define SHADER_UNIFORM_TEXTURE "u_texture"
@@ -314,5 +333,6 @@ const ShaderData SHADER_DATA[SHADER_COUNT] =
 {
   {SHADER_VERTEX, SHADER_FRAGMENT},
   {SHADER_VERTEX, SHADER_TEXTURE_FRAGMENT},
+  {SHADER_AXIS_VERTEX, SHADER_FRAGMENT},
   {SHADER_GRID_VERTEX, SHADER_GRID_FRAGMENT}
 };

src/canvas.cpp

@@ -33,7 +33,7 @@ void canvas_init(Canvas* self, const ivec2& size)
     glBufferData(GL_ARRAY_BUFFER, sizeof(CANVAS_AXIS_VERTICES), CANVAS_AXIS_VERTICES, GL_STATIC_DRAW);
  
     glEnableVertexAttribArray(0);
-    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 2 * sizeof(f32), (void*)0);
+    glVertexAttribPointer(0, 1, GL_FLOAT, GL_FALSE, sizeof(f32), (void*)0);
     
     // Grid
     glGenVertexArrays(1, &self->gridVAO);
@@ -96,6 +96,8 @@ void canvas_init(Canvas* self, const ivec2& size)
     glGenFramebuffers(1, &self->fbo);
     glGenRenderbuffers(1, &self->rbo);
     _canvas_framebuffer_set(self, size);
+
+    self->isInit = true;
 }
 
 mat4 canvas_transform_get(Canvas* self, vec2 pan, f32 zoom, OriginType origin)
@@ -197,11 +199,17 @@ void canvas_rect_draw(Canvas* self, const GLuint& shader, const mat4& transform,
 
 void canvas_axes_draw(Canvas* self, GLuint& shader, mat4& transform, vec4& color)
 {
+    vec4 originNDC = transform * vec4(0.0f, 0.0f, 0.0f, 1.0f);
+    originNDC /= originNDC.w;
+
     glUseProgram(shader);
     glBindVertexArray(self->axisVAO);
-    glUniformMatrix4fv(glGetUniformLocation(shader, SHADER_UNIFORM_TRANSFORM), 1, GL_FALSE, value_ptr(transform));
-    glUniform4f(glGetUniformLocation(shader, SHADER_UNIFORM_COLOR), color.r, color.g, color.b, color.a);
-    glDrawArrays(GL_LINES, 0, 4);
+    glUniform4fv(glGetUniformLocation(shader, SHADER_UNIFORM_COLOR), 1, value_ptr(color));
+    glUniform2f(glGetUniformLocation(shader, SHADER_UNIFORM_ORIGIN_NDC), originNDC.x, originNDC.y);
+    glUniform1i(glGetUniformLocation(shader, SHADER_UNIFORM_AXIS), 0);
+    glDrawArrays(GL_LINES, 0, 2);
+    glUniform1i(glGetUniformLocation(shader, SHADER_UNIFORM_AXIS), 1);
+    glDrawArrays(GL_LINES, 0, 2);
     glBindVertexArray(0);
     glUseProgram(0);
 }
@@ -218,6 +226,8 @@ void canvas_unbind(void)
 
 void canvas_free(Canvas* self)
 {
+    if (!self->isInit) return;
+
     glDeleteFramebuffers(1, &self->fbo);
     glDeleteRenderbuffers(1, &self->rbo);
     glDeleteTextures(1, &self->framebuffer);

src/canvas.h

@@ -10,18 +10,11 @@
 #define CANVAS_GRID_MIN 1
 #define CANVAS_GRID_MAX 1000
 #define CANVAS_GRID_DEFAULT 32
-#define CANVAS_LINE_LENGTH (FLT_MAX * 0.001f)
 
 const inline vec2 CANVAS_PIVOT_SIZE = {8, 8};
 const inline vec2 CANVAS_SCALE_DEFAULT = {1.0f, 1.0f};
 
-const inline f32 CANVAS_AXIS_VERTICES[] = 
-{
-    -CANVAS_LINE_LENGTH, 0.0f,
-    CANVAS_LINE_LENGTH, 0.0f,
-    0.0f, -CANVAS_LINE_LENGTH,
-    0.0f, CANVAS_LINE_LENGTH
-};
+const inline f32 CANVAS_AXIS_VERTICES[] = {-1.0f, 1.0f};
 
 const inline f32 CANVAS_GRID_VERTICES[] =
 {
@@ -62,6 +55,7 @@ struct Canvas
     GLuint textureEBO{};
     ivec2 size{};
     ivec2 previousSize{};
+    bool isInit = false;
 };
 
 #define UV_VERTICES(uvMin, uvMax) \

src/imgui.cpp

@@ -2404,9 +2404,9 @@ static void _imgui_spritesheet_editor(Imgui* self)
 			if (!texture) break;
 			
 			vec4 color = tool == TOOL_ERASE ? COLOR_TRANSPARENT : toolColor;
-			
+
 			if (isMouseClick)
-				imgui_snapshot(self, IMGUI_ACTION_DRAW);
+				imgui_snapshot(self, tool == TOOL_DRAW ? IMGUI_ACTION_DRAW : IMGUI_ACTION_ERASE);
 
 			if (isMouseDown)
 				texture_pixel_set(texture, position, color);
@@ -2661,12 +2661,6 @@ void imgui_update(Imgui* self)
 				break;
 		}
 	}
-
-	if (map_find(self->anm2->layers, -1))
-		printf("Layers -1\n");
-
-	if (map_find(self->anm2->spritesheets, -1))
-		printf("Spritesheets -1\n");
 }
 
 void imgui_draw(void)
@@ -2677,6 +2671,8 @@ void imgui_draw(void)
 
 void imgui_free(void)
 {
+    if (!ImGui::GetCurrentContext()) return;
+	
 	ImGui_ImplSDL3_Shutdown();
 	ImGui_ImplOpenGL3_Shutdown();
 	ImGui::SaveIniSettingsToDisk(settings_path_get().c_str());

src/imgui.h

@@ -69,6 +69,7 @@
 #define IMGUI_ACTION_FRAME_DELAY "Frame Delay"
 #define IMGUI_ACTION_MOVE_PLAYHEAD "Move Playhead"
 #define IMGUI_ACTION_DRAW "Draw"
+#define IMGUI_ACTION_ERASE "Erase"
 #define IMGUI_ACTION_RELOAD_SPRITESHEET "Reload Spritesheet(s)"
 #define IMGUI_ACTION_REPLACE_SPRITESHEET "Replace Spritesheet"
 
@@ -1564,17 +1565,17 @@ IMGUI_ITEM(IMGUI_TOOL_COLOR_PICKER,
 
 IMGUI_ITEM(IMGUI_TOOL_UNDO,
     self.label = "## Undo",
-    self.tooltip = "Undoes the last action.",
+    self.tooltip = "Undo the last action.",
     self.function = imgui_undo,
-    self.chord = ImGuiKey_Z,
+    self.chord = ImGuiMod_Ctrl | ImGuiKey_Z,
     self.atlas = ATLAS_UNDO
 );
 
 IMGUI_ITEM(IMGUI_TOOL_REDO,
     self.label = "## Redo",
-    self.tooltip = "Redoes the last action.",
+    self.tooltip = "Redo the last action.",
     self.function = imgui_redo,
-    self.chord = ImGuiMod_Shift + ImGuiKey_Z,
+    self.chord = ImGuiMod_Ctrl | ImGuiKey_Y,
     self.atlas = ATLAS_REDO
 );
 
@@ -2036,8 +2037,6 @@ IMGUI_ITEM(IMGUI_CHANGE_INPUT_INT,
     self.step = 0
 );
 
-
-
 #define IMGUI_OPTION_POPUP_ROW_COUNT 2
 IMGUI_ITEM(IMGUI_POPUP_OK,
     self.label = "OK",

src/preview.cpp

@@ -81,6 +81,7 @@ void preview_draw(Preview* self)
     ivec2& gridOffset = self->settings->previewGridOffset;
     vec4& gridColor = self->settings->previewGridColor;
     GLuint& shaderLine = self->resources->shaders[SHADER_LINE];
+    GLuint& shaderAxis = self->resources->shaders[SHADER_AXIS];
     GLuint& shaderTexture = self->resources->shaders[SHADER_TEXTURE];
     GLuint& shaderGrid = self->resources->shaders[SHADER_GRID];
     mat4 transform = canvas_transform_get(&self->canvas, self->settings->previewPan, self->settings->previewZoom, ORIGIN_CENTER);
@@ -95,7 +96,7 @@ void preview_draw(Preview* self)
         canvas_grid_draw(&self->canvas, shaderGrid, transform, gridSize, gridOffset, gridColor);
 
     if (self->settings->previewIsAxes)
-        canvas_axes_draw(&self->canvas, shaderLine, transform, self->settings->previewAxesColor);
+        canvas_axes_draw(&self->canvas, shaderAxis, transform, self->settings->previewAxesColor);
 
     Anm2Animation* animation = anm2_animation_from_reference(self->anm2, self->reference);
     s32& animationID = self->reference->animationID;

src/shader.cpp

@@ -47,5 +47,7 @@ bool shader_init(GLuint* self, const std::string& vertex, const std::string& fra
 
 void shader_free(GLuint* self)
 {
+	if (*self == GL_ID_NONE) return;
+	
 	glDeleteProgram(*self);
 }

src/state.cpp

@@ -30,6 +30,7 @@ void init(State* self)
 	{
 		log_error(std::format(STATE_SDL_INIT_ERROR, SDL_GetError()));
 		quit(self);
+		return;
 	}
 
 	log_info(STATE_SDL_INIT_INFO);
@@ -69,8 +70,8 @@ void init(State* self)
 	);
 
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
-   	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
-   	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
+   	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, STATE_GL_VERSION_MAJOR);
+   	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, STATE_GL_VERSION_MINOR);
 
 	self->glContext = SDL_GL_CreateContext(self->window);
 	
@@ -78,14 +79,14 @@ void init(State* self)
 	{
 		log_error(std::format(STATE_GL_CONTEXT_INIT_ERROR, SDL_GetError()));
 		quit(self);
+		return;
 	}
 
-	GLenum glewError = glewInit();
-
-	if (glewError != GLEW_OK)
+	if (!gladLoadGLLoader((GLADloadproc)SDL_GL_GetProcAddress)) 
 	{
-		log_error(std::format(STATE_GL_CONTEXT_INIT_ERROR, (const char*)glewGetErrorString(glewError)));
+		log_error(std::format(STATE_GLAD_INIT_ERROR));
 		quit(self);
+		return;
 	}
 
 	log_info(std::format(STATE_GL_CONTEXT_INIT_INFO, (const char*)glGetString(GL_VERSION)));

src/state.h

@@ -9,6 +9,7 @@
 #define STATE_MIX_AUDIO_DEVICE_INIT_WARNING "Unable to initialize audio device! {}"
 #define STATE_MIX_INIT_INFO "Initialized SDL_mixer"
 #define STATE_GL_CONTEXT_INIT_ERROR "Failed to initialize OpenGL context! {}"
+#define STATE_GLAD_INIT_ERROR "Failed to initialize GLAD!"
 #define STATE_GL_CONTEXT_INIT_INFO "Initialized OpenGL context (OpenGL {})"
 #define STATE_QUIT_INFO "Exiting..."
 #define STATE_GL_LINE_WIDTH 2.0f
@@ -23,6 +24,9 @@
 #define STATE_MIX_DEVICE NULL
 #define STATE_MIX_ALLOWED_CHANGES SDL_AUDIO_ALLOW_FORMAT_CHANGE
 
+#define STATE_GL_VERSION_MAJOR 3
+#define STATE_GL_VERSION_MINOR 3
+
 struct State
 {
 	SDL_Window* window;

src/texture.cpp

@@ -114,6 +114,8 @@ bool texture_from_gl_write(Texture* self, const std::string& path)
 
 void texture_free(Texture* self)
 {
+	if (self->isInvalid) return;
+
 	glDeleteTextures(1, &self->id);
 	*self = Texture{};
 }